What ECU would fit instead of a red label one?

[overboost]

The LH does have long and short term trim. It's not just active at idle either. That's why these cars can go a bit strange if the oxygen sensor goes haywire. The CO pot is there to make up for tolerances, in both the electronics, and the engine. Modern cars have the same adjustments, but since they have the advantage of flash memory, the adjustments are stored in NVRam. The LH doesn't have any storage that survives for long without the battery connected, so has a potentiometer.

where does the LH store this information then...??? also the LH, or EZK don't have constant 12V supply rails to them. Only switched from ignition, so how is it gonna keep its info........???????

The LH doesn't have to be that smart, it;s looking at the input from the air mass meter, so it can put in the right ammount of fuel easily. It doesn't need to do anything fancy to do that. It has some tables of fuel trim, and a map of sorts to allow for quirks of the intake to the MAF (the bend right before the inlet mostly).

The fuel trim tables are for the likes of cold running enrichment, full throttle enrichment, accelerator pump effect and idle speed table. I presume you mean the concertina style intake pipe...??? If it's compensating for that, then how come they run fine with a normal SAMCO bend...??? with no lambda sensor connected..??

Volvo say it is able to retard the ignition on a per cylider basis, as well as reduce the boost if required. Are you going to argue with them as well?

Yes. since there is no camshaft sensor to tell when the engines at cylinder 1. therfore it cannot retard per cylinder, unless it remembered which cylinder had been pinking, and then counted 4 sparks and retarded the timing there. All a bit too complex for the LH processor.
Of course it can reduce the boost, it has full control over that. If it heard detonation it would firstly retard the ignition and if it continued, i would assume reduce the boost level

Proving the ECU is aware of torque is easy too. Put a standard car on a dyno, and do some part throttle runs (somewhere between 60 and 100% throttle). You will be able to see that the pressure over the throttle butterfly is near zero most of the time, but that you get some fairly flat torque curves. Now try it with another car (say with K-jet, like and RS turbo) you get a completly different torque curve, one that starts out going quite high, and drops off as the pressure changes over the throttle valve.

I don't quite understand what you are getting at here. I presume you are referring to the fact that Volvo wanted to make the car useable for everyone, so therefore at part throttle, the EZK bleeds less pressure off than at full throttle. Therefore limiting the available power. This does not mean it is torque based. That is a completely different kettle of fish

'Ignition timing vs boost tradeoff' is a fancy way of saying it retards the ignition with boost pressure. I don't see how this is a great trick....

This has been interesting.

Richard

It certainly is

[chris1roll]

Right, apologies to those who aren't interested, for a mega post, however you should all have mice with scrolly wheely thingy's....

I haven't copied the pictures because I don't believe them to be 100% necessary for the discussion, but otherwise, This is a direct Cut and paste from a text i came across , [...] indicates where i have omitted text relating to the E/ES/EP/FP systems:



Operating programs of the LH 2.2 fuel injection system

Start program
A special start program in the ECU provides two fuel injections for each engine cycle (360° of crankshaft rotation) until the engine speed is approximately 600 r/min.
During the first few cycles, the open duration of the double injections is determined by the ECU start program. After the first double injections, the quantity of fuel injected during the double injections will depend upon:

-the speed at which the starter motor cranks the engine;
-the engine temperature;
-the engine starting time (i.e. duration, determined by the number of engine revolutions).

To rule out the possibility of flooding the engine, the ECU will decrease the quantity of injected fuel as the starting time increases.

Combined choke/warm–up program
When the engine reaches approximately 600 r/min, the ECU considers that the engine has started and reduces the double injections to one injection for each cycle.
As the engine has just started and is therefore still cold, it will need a richer mixture to keep running smoothly. The ECU monitors engine temperature, engine speed, and how long the engine has been running (determined by the number of engine revolutions). The ECU uses this information to increase the open duration of the injectors beyond the 'normal' operating program time which is stored in the normal operating temperature program. As the engine temperature increases, the increased open time of the injectors is reduced.

Normal operating temperature program
As soon as the engine has reached normal operating temperature, the quantity of injected fuel is determined by a program which monitors engine speed and engine load as determined by the air mass flow meter.

Fuel cut–off program
The ECU will stop the injectors opening if the throttle valve is closed and the engine speed is above a certain value.
This action:

-improves fuel economy;
-produces cleaner exhaust emissions;
-provides better engine braking.

The engine speed at which injector cut–off occurs depends upon the following engine coolant temperatures:
-–40°C=4950 r/min
-+ 20°C=2600 r/min
-+80°C=1400 r/min

Overspeed protection program
To prevent engine damage due to excessive engine speed, the ECU will start reducing the injector open time at 6242 r/min. The reduced open time will continue until the engine speed falls below this value.

Note! When the engine speed is lower than 45 r/min, the ECU will shut off the fuel pump by de–energizing the master relay. This action ensures that the fuel pump does not operate when the engine has stopped with the ignition still switched on.

.....

The LH 2.2 system adjusts the engine speed as follows:

TemperatureEngine Speed
+ 80°C800 r/min.
+20°C950 r/min.
−40°C1200 r/min.

...

Operating program of the EZ 210K ignition system
The B18FT engine has an ignition ECU (EZ 210K) which is designed to control the ignition timing and the boost pressure of the turbocharger unit. Also see under 'Boost pressure control system'.
The operation of the ignition system is controlled by the EZ 210K ECU (5) which has a memory containing ignition timing data referenced to engine speed and engine load conditions. This system will also reduce the boost pressure if the engine overheats, or if the engine continues to knock after the ignition system has exceeded a threshold value of average ignition advance adjustment.

The EZ 210K ECU receives input signals from the following sensors:
-engine speed and crankshaft angle, detected by the flywheel sensor (8);
-engine temperature, sensed by engine temperature sensor (9);
-engine knock, detected by the knock sensor (11);
-inlet pressure, transmitted to the EZ 210K ECU (5) via an air line;
-throttle valve position, monitored by the throttle valve position sensor (3) for:
-engine idling speed;
-acceleration;
-full load enrichment;
-fuel cut–off.

Inlet pressure sensor
Engine load is sensed by monitoring the pressure variations which occur in the inlet manifold. The inlet manifold is connected to a pressure sensor in the EZ 210K ECU via a line which is connected to a nipple on the throttle valve housing.
The pressure sensor converts the pressure changes which occur in the manifold into electrical signals. The operation is comparable to that of the diaphragm valve. The signals are processed in the EZ 210K ECU and are transmitted to the transistor controlled ignition coil and to the boost pressure regulating valve.

Electronic Control Unit
For every combination of engine speed and inlet manifold depression, the correct ignition advance is stored in the memory of the EZ 210K.
In the adjacent map the ignition advance (A) is plotted as a function of engine speed (C) and inlet manifold pressure (B).
Based on these data, the knock sensor and coolant temperature sensor are able to signal the EZ 210K ECU to advance or retard the ignition timing point in order to maintain optimum engine operating conditions.
-A Ignition advance
-B Inlet manifold pressure
-C Engine speed

Adjustment via control signals from the knock sensor

Dynamic adjustment
occurs in transient conditions, as when the accelerator is abruptly depressed to full throttle, and instantly retards the ignition timing point of all cylinders by 3° irrespective of the cylinder(s) in which knocking is occurring. After 0.5 seconds the adjustment is either re–advanced or changed to a value set by the slow or fast adjustment mode.

Slow adjustment
simultaneously retards the ignition timing point of all cylinders by 1° per step until the knocking stops. When the knocking stops, after a certain time has elapsed the ignition timing will be advanced again at a rate of 1° per 1000 r/min.

[I think this is interesting, so it can retard on an individual basis, as Richard said.]:

Fast adjustment
is a selective mode which detects when one individual cylinder is knocking. The mode then progressively retards each successive ignition timing point by 3° to 4° When the knocking stops, the applied adjustment will be re–advanced at a rate of 1° per 120 r/min. The total adjustment range of the system with all three modes operative is 10°.

Boost pressure control system

General
On turbocharged engines the boost pressure is frequently set at a certain maximum value. This is done using a diaphragm valve which is connected to an excess pressure valve (a wastegate or dump valve). The diaphragm valve is in direct communication with the inlet manifold. When the boost pressure in the inlet manifold has almost reached the maximum value, the wastegate in the turbocharger opens to prevent any further increase in boost pressure.
On the turbocharged engine fitted in the V400 (B18FT) the excess pressure is regulated. In this case, the diaphragm valve, which is normally in direct communication with the inlet manifold, receives a controlled charge of boosted air. This is done with an electrically controlled boost pressure regulating valve. The electrical control system (software) is in the EZ 210K, in other words the same ECU as that of the ignition system.
In the EZ 210K ignition and boost pressure control system, the diaphragm valve is connected to the inlet manifold via the boost pressure regulating valve. The valve is controlled by the EZ 21 OK ECU and allows independent control of the pressure applied to the diaphragm valve.
The advantage of the boost pressure control system is that a physically smaller turbocharger unit can be used, which responds faster and consequently builds up pressure more quickly. This faster response gives a higher boost pressure at low engine speeds.
The wastegate on the turbocharger unit of the B18FT engine is opened by the diaphragm valve at a pressure of approximately 17.5 kPa; at this moment the pressure in the inlet system is approximately 55 kPa. The effect of the boost pressure regulating valve is to reduce the high boost pressure (55 kPa) to the lower diaphragm opening pressure of 17.5 kPa.

Overview of the boost pressure control system
Air is induced into the engine by the compressor of the turbocharger unit (10) via the air filter (1), the air mass flow meter (2), the intercooler (15) and the inlet manifold and is then discharged via the turbine of the turbocharger unit to the exhaust system.
The exhaust gases which drive the turbine pass through a section of the turbocharger unit in which a bypass connection, controlled by the wastegate (13), is fitted. The wastegate is operated by the diaphragm valve (12). The pressure admitted to the diaphragm valve is controlled via the boost pressure regulating valve (7).
The boost pressure regulating valve (7) regulates the pressure acting on the diaphragm valve (12) and is controlled by the EZ 210K ECU (5).
-1 Air filter
-2 Air mass flow meter
-3 Throttle valve position sensor
-4 LH 2.2 ECU
-5 EZ 210K ECU
-6 Load sensing pipe (boost pressure)
-7 Boost pressure regulating valve
-8 Engine speed/ignition sensor
-9 Coolant temperature sensor
-10 Turbocharger unit
-11 Knock sensor
-12 Diaphragm valve
-13 Wastegate
-14 Throttle valve
-15 Intercooler
-16 Boost pressure gauge

Boost pressure regulating valve
Boost pressure from the inlet system is applied to port (1) and presses valve disc (5) on to valve seat (9) against the pressure of spring (6). Boost pressure now builds up and is applied to the diaphragm valve via holes in valve disc (5) and port (7).
A small proportion of the boost pressure is bled to the low pressure air inlet of the turbocharger unit via port (8). As the boost pressure and the diaphragm valve are ported to each other, almost the same pressure exists in each, and the diaphragm valve will open the wastegate at a pressure of 17.5 kPa.
When solenoid (3) is energized by the EZ 210K ECU, valve disc (5) is pulled on to valve seat (4) and boost flow is cut off. The diaphragm valve is now ported to the air inlet side of the engine, the diaphragm valve closes the wastegate and boost pressure increases.
-1 Inlet pressure (boost pressure)
-2 Electrical connector
-3 Solenoid
-4 Valve seat
-5 Valve disc
-6 Spring
-7 Outlet port (to wastegate)
-8 Outlet port (to air inlet)
-9 Valve seat

The solenoid (3) is energized by current pulses occurring at a frequency of 128 Hz and having a duration of between 0 to 50%. With a long pulse duration (A), valve disc (5) will remain on valve seat (4) for 40% of the pulse time, the diaphragm valve closes the wastegate, and boost pressure increases.
With a short pulse duration (B) (20%), valve disc (5) is forced on to valve seat (9) and high boost pressure is applied to the diaphragm valve which opens the wastegate, so that the boost pressure decreases.
Boost pressure is therefore controlled by the EZ 210K ECU which is programmed to position valve disc (5) between valve seats (4) and (9) for all engine operating conditions.

Software – boost pressure control system
The ECU continuously monitors the following engine conditions: coolant temperature, engine speed and crankshaft position, engine load and boost pressure. Depending on these conditions, the ECU will signal boost pressure regulating valve (7) to port more, or less pressure to diaphragm valve (12) which, in turn, will open or close wastegate (13).
If wastegate (13) opens, exhaust gases will bypass the turbine of turbocharger unit (10) which will run at a slower speed, so also reducing the quantity of air induced into the inlet manifold. If the wastegate closes, the reverse sequence will occur and the quantity of induced air will increase.
The system regulates the engine's boost pressure loading during all normal operating conditions. Furthermore, the system will reduce the boost pressure if the engine knocks and the applied retardation of the ignition timing (due to knock) has exceeded its specified maximum value.
The EZ 210K system therefore provides protection against excessive boost pressure. When boost pressure exceeds 90kPa, and if the engine speed exceeds 2021 r/min, the ECU stops sending the engine speed signal to the LH 2.2 ECU, which then stops the injectors operating. At the same time, the EZ 210K ECU de–energizes the boost pressure regulating valve, which limits the maximum boost pressure to 28 kPa.
When the engine speed is lower than 2021 r/min, the boost pressure protection system is inoperative and the car can be driven to a workshop.
If the EZ 210K ECU does not receive a load signal (for example, if the load sensor in the EZ 210K ECU is defective) the ECU will select the full load ignition curve and will de–energize the boost pressure regulating valve.
When the EZ 210K ECU receives a load signal which is low in comparison with other engine operating parameters (for example a loose hose connection, or air leaks at the ECU connector) the EZ 210K ECU will not energize the boost pressure regulating valve when the engine speed exceeds 2700 r/min. In this condition the boost pressure is limited to 28 kPa.

Note! the pressures stated above do not apply to pre–1991 B18FT engines. For these values see the Repairs & Maintenance Service manual, Section 2, B18F/FT "Checking/adjusting the boost pressure" .

...

Flywheel sensor
Engine speed and crankshaft position data are transmitted to the ECU via the flywheel sensor (1). The sensor has a permanent magnet (A) and an induction coil (B) and is in circuit with the ECU. The teeth of the gear ring (2) rotate past the sensor and induce a continuously changing magnetic field into the sensor which converts this into AC voltage.
The gear ring on the flywheel has 40 teeth* which are spaced evenly around the circumference. Two of the teeth and gaps are twice as wide and are located at 180( to each other.
When a wide tooth passes the sensor, the signal changes and the ECU then knows that Top Dead Centre (TDC) will be reached 90 degrees later.
* B20F, B18F, B18FT and B18U engines, model year 1994, have a different flywheel with 58 teeth and only one gap.

[Oh, there we go! different teeth numbers, as Richard said!]

...

Air mass flow meter

The air mass flow meter is the most important sensor in the LH 2.2 fuel injection system. This sensor is able to measure the air mass without the help of other sensors. The measurement is done with a heated wire, which it is why it is called a 'hot wire system'.
The mass of air induced into the engine is sensed by the air mass flow meter. The induced air passes through mesh filter (7), into housing (8), through sensing tube (6) and on to the engine.
Sensing tube (6) contains a platinum element (9) whose temperature is kept 100°C above the ambient air temperature. As the induced air passes the element, the element is cooled and its temperature drops. The additional current which is needed to maintain the 100°C difference is a measure of the mass of air induced into the engine.
The platinum element is connected to the LH 2.2 ECU via electrical connector (2). The LH 2.2 ECU measures the additional current needed to maintain the temperature difference at a constant level and from this measurement computes a 'basic injection phase' which is then modified by data output from the temperature sensor which is fitted on the engine.
-1 Cover
-2 Electrical connector
-3 Plug
-4 CO–adjustment screw
-5 Hybrid circuit
-6 Sensing tube
-7 Mesh filter
-8 Housing
-9 Platinum element

Automatic cleaning program
The platinum element is a critical part of the air mass flow meter and must be kept clean to ensure accurate operation. Cleaning is done by an automatic cleaning procedure, initiated by the LH 2.2 ECU four seconds after the engine has been switched off. The automatic program will only be started if the engine speed had exceeded 2000 r/min and if the coolant temperature had exceeded 60°C. When these conditions are met, the ECU sends a signal to the air mass flow meter which causes the platinum element to be heated to 1050°C for one second. This rapid temperature rise burns off any dirt which may have been deposited on the element.

Adjustment
The percentage of carbon monoxide (CO) at idling speed can be adjusted with CO–adjustment screw (4). To get to the screw, the plug (3) must be removed by drilling two small holes in it and then using a suitable tool to remove the plug. The CO–adjustment screw operates a potentiometer which has a 15 turn adjustment range.

Limp mode – LH 2.2
If the platinum element breaks, the LH 2.2 ECU will start an emergency program called 'limp mode'. This program allows the fuel injection time to depend only upon engine speed as follows:
engine speed below 1000 r/min = 3.5 ms
engine speed above 1000 r/min = 6.5 ms

...

LH 2.2 terminal connections–B18F/FT/FTM

Pin 1Receives engine speed signal from ignition ECU (33).
Pin 2Receives coolant temperature signal from sensor (13).
Pin 3Receives throttle–closed signal from throttle valve position sensor (11).
Pin 4+50 connection (FT/FTM only).
Pin 5Grounds injection ECU and screening cable for oxygen sensor (12).
Pin 6Signal ground connection for air mass flow meter (30).
Pin 7Receives load signal from air mass flow meter (30).
Pin 8Sends a control signal to air mass meter (30) to heat the hot wire in order to burn off any deposits.
Pin 9Battery voltage controlled by the system relay.
Pin 10Controls the idle speed regulating valve (8).
Pin 11Ground
Pin 12Full load signal from throttle valve position sensor(11); connects idle speed test point (11.1).
Pin 13Grounds the power supply to the injectors (7).
Pin 14Receives reference signal for CO–adjustment at idle from flow air mass flow meter (30).
Pin 1512 V.
Pin 16Receives a signal as soon as air conditioning is engaged in order to compensate for the additional load by adjusting the idle speed.
Pin 17Grounds the master relay (3) when the engine speed is higher than 45 r/min.
Pin 18Receives battery voltage for the LH 2.2 ECU (1) via the ignition switch (5).
Pin 19FT: grounds the water pump relay after ignition switched off.
F: ground connection.
Pin 20Receives a signal from the oxygen sensor.
Pin 21Grounds the system relay (2).
Pin 22Test point for oxygen sensor.
Pin 23The same point as pin 10. sends constant idle speed regulating valve (8)
Pin 24FT: transmits a pulse train to the EZ 210K to send control signals to the mapping field.
Pin 25Ground

....

EZ 210K ECU terminal connections

Pin 2Receives coolant temperature signal from sensor (13).
Pin 3Diagnostic test point (20) (up to 1991).
Pin 4Sends full load and acceleration signal to LH 2.2 ECU (1) for mixture enrichment.
Pin 5Receives battery voltage from ignition switch (5) (up to 1991)
Pin 6Receives battery voltage from ignition switch (5).
Pin 7Receives throttle–closed signal from throttle valve position sensor (11) via LH 2.2 ECU (1)
Pin 8Receives a pulse train from the LH 2.2 to send control signals to the mapping field.
Pin 10/23Receives engine speed signal from flywheel sensor (17).
Pin 11Screening cable for flywheel sensor (17).
Pin 12Screening cable for knock sensor (16).
Pin 13Receives signal from knock sensor (16).
Pin 14Ground.
Pin 15Controls boost pressure regulating valve (34).
Pin 16Sends ignition signal to transistor controlled ignition coil (36)
Pin 17Sends engine speed
Pin 20Ground.
Pin 21Screening cable for throttle valve position sensor (11).
Pin 22Sends battery voltage to throttle valve position sensor.
Pin 25Receives potentiometer signal from throttle valve position sensor.


That should give you two something to talk about? Hope it helps.

[overboost]

If you read the flywheel teeth section correctly, it says that the B20F, B18F, B18FT engines have 58 teeth with a gap. i.e. 60-2 and also the B18U of model year 1994.

If the teeth were different then the ecu's i added wires to would still not run.

The 40 teeth pattern relates to the renix/bendix ignition units.

And as for the knock adjustment i stand corrected. And i must admit am extremely surprised Learn something every day.

[chris1roll]

If you read the flywheel teeth section correctly, it says that the B20F, B18F, B18FT engines have 58 teeth with a gap. i.e. 60-2 and also the B18U of model year 1994.

If the teeth were different then the ecu's i added wires to would still not run.

The 40 teeth pattern relates to the renix/bendix ignition units.

Maybe, but that is not how it reads, if you actually do read it correctly.

* B20F, B18F, B18FT and B18U engines, model year 1994, have a different flywheel with 58 teeth and only one gap.

Right:

B20F comma
B18F comma
B18FT and B18U engines comma model year 1994 There is no comma between the two engine types here, because you don't put commas before the last item in a list, where you us "and" (I cant remember the word for this, been a while since I was at school)
The "s" on the end of engines, applies either to all the engine designations listed, or implies the obvious, that there was more than on B18U made in 1994!
Now, the final comma, is the critical one, if it wasn't there, then the model year 1994 part would apply to just the B18U, however because it is there, what comes after applies to all the engine designations.

It might not be true, but that is what it says.


Like the legislation only relatively recently repealed, where a misplaced comma legalised slavery in this country.

EDIT: I was wrong, it was the state of Michegan:
"Neither slavery nor involuntary servitude, unless for the punishment of crime, shall ever be tolerated in this state." Thus read the state of Michigan's constitution in 1850. Inadvertently, it legalized slavery as an appropriate punishment for crime. Not until 1963 was the comma shifted from its position after servitude to a position after slavery, and slavery was once again outlawed in the state.

Tricky things, these commas eh?

Chris

[rpruen]

where does the LH store this information then...??? also the LH, or EZK don't have constant 12V supply rails to them. Only switched from ignition, so how is it gonna keep its info........???????

It does have a feed. It stores fault codes, and switches on the waterpump after the ignition is switched off.

The fuel trim tables are for the likes of cold running enrichment, full throttle enrichment, accelerator pump effect and idle speed table. I presume you mean the concertina style intake pipe...??? If it's compensating for that, then how come they run fine with a normal SAMCO bend...??? with no lambda sensor connected..??

No I mean the exit of the airbox, it's a 90 degree elbow, and will have an effect on the reading of the airflow meter. Table and map are the same thing, I tend to follow what Bosch use, a table is a 2D map, and a map is a 3D map. All maps are lookup tables anyway as far as the microprocesor is concerened.

The LH uses a 2D table (or map) to correct the airflow to alow for this. Since it depends only on the airflow, not engine load, a 2D table is fine for this.

Also the offset that is applied is quite small, so it doesn't have that huge an effect if you remove the bend. The outlet of the MAF and anything after that has next to no effect on the measured airflow in practial terms. So that isnt going to be an issue.

Yes. since there is no camshaft sensor to tell when the engines at cylinder 1. therfore it cannot retard per cylinder, unless it remembered which cylinder had been pinking, and then counted 4 sparks and retarded the timing there. All a bit too complex for the LH processor.

Except that is exactly what it does. Chris already posted the info. So I'll leave it at that.

I don't quite understand what you are getting at here. I presume you are referring to the fact that Volvo wanted to make the car useable for everyone, so therefore at part throttle, the EZK bleeds less pressure off than at full throttle. Therefore limiting the available power. This does not mean it is torque based. That is a completely different kettle of fish

Except that the torque curve you get is very flat, more so than you would expect. It's not a simple reduction in boost, but the ECU is aware of the torque the engine is producing. The ECU wouldn't need the load signal from the LH and a map sensor if it wasn't torque based, it would use one or the other, but not both.

Plus it has a torque map, a firly good indication.

'Ignition timing vs boost tradeoff' is a fancy way of saying it retards the ignition with boost pressure. I don't see how this is a great trick....

Not at all. It sees the throttle position as a torque request, and then manipulates the timing, and boost to try to achieve the desired torque. If the engine knocks, then it will retard the timing and increase the boost instead.

Throw in some very low octane petrol and test this out if you like.

Richard

[martinholmesuk]

Thanks Chris, some very good information

[overboost]

I knew when i entered into this discussion that everything i said would be knocked by more than yourself richard.

I can see i'm fighting a losing battle, and i'll have to have my own opinions.

I will say though, that the neither ecu has a power feed constantly. Yes, the auxillary waterpump and its relay do, but not the ecu's. There is a seperate circuit with its own sensor to turn on the waterpump relay. I double checked this before i posted it. I will scan the wiring diagrams if u wish to confirm this.....

Andy

[rpruen]

I knew when i entered into this discussion that everything i said would be knocked by more than yourself richard.

Fair enough. I have no control over other people, they can say what they like.

I can see i'm fighting a losing battle, and i'll have to have my own opinions.

You are quite welcome to them, even if they are wrong. No one can take that away from you.

I will say though, that the neither ecu has a power feed constantly. Yes, the auxillary waterpump and its relay do, but not the ecu's. There is a seperate circuit with its own sensor to turn on the waterpump relay. I double checked this before i posted it. I will scan the wiring diagrams if u wish to confirm this.....

Andy

Ok... Please do, but don't email them to me, thanks. It's just that my internet conection is not unlike a damp bit of string.

That is quite strange, because the ECU does have a feed. Since you have a later car, then if you follow the wiring, the Aux waterpump is controlled by the ECU. There is an extra thermal switch bolted to the intake manifold that will run the pump as well. The early cars did have a seperate timer relay for the water pump, but yours won't. The electrical drawings on the club site show it, if that is any help.

Loads of ways to verify that, follow the wires, or switch off the engine, and unplug the fuel ecu. The moment you unplug it the pump will stop (unless the intake manifold thermal switch is above 95 degC).

Richard

[chris1roll]

I knew when i entered into this discussion that everything i said would be knocked by more than yourself richard.

Oh good grief!


So far I have posted the information volvo themselves hold, and picked out the bits of relevance, what got my goat was:

If you read the flywheel teeth section correctly

when as I pointed out, I had. You may note however, I also said that it may not necessarily be true, (i.e. you could be correct) and that volvo's own grammar may be suspect.

I can see i'm fighting a losing battle, and i'll have to have my own opinions. Smile

Ditto Richard.


I think any "knocking" started about here:

When does the EZK do these 'things'. .??? when its dreaming of being a much more modern system.

Perhaps being less agumentative and more discursive might allow us all to learn some things?
Especially since I know naff all about electronics.

Chris

[VanDerGraaf]

I must concur with Chris here Andy, as an innocent (and somewhat enthralled) reader of this thread, I have found your tone to be somewhat less than good-natured towards Richard.
A bit uncalled for perhaps?

[stargate1961]

Hi, is the Ecu responsable of the ignition/fuel management? 'cose the engine of my turbo ( 87 ) most of the time run on 3 cilinder it has asmatic symptoms, I thought can be the rotor and or the rotor cap,
Ps. See my Q. in Engine sector, thx for your help in advantage
Grtx
Stargate

[robkendall]

there seems to be a trend of 'knock richard' for whatever reasons everyone quotes "well i will just have my own opinions then" but doesnt seem inclined to pay richard the same courtesy whilst other people profess to know all this information and different information only richard has put his knowledge to practical use and offered it to other members thus 'proving' that what he knows works where as other peoples opinions are just that oh and ive put no punctuation in this at all so read it how you want
(well except for the odd quote marks and these parentheses)

rgrds
rob

[glasgowjim]

Bumped this thread up as it answers a number of questions asked recently about ecus and swopping them.

[B18FT - LOVER]

Yes a blue ECU will work, if the purple/orange one doesn't.

The cars fitted with red (maroon) ecus can have two possible flywheels, either the smaller early type clutch, or the later bigger one. The blue ECU goes with the later type clutch, and the orange or purple ECU with the early type.

Idealy you need to swap the Fuel ECU and MAF as well as the boost ECU as a set. Unless it's a temparary solution to keep the car running.

Regards

Richard

Perhaps you can help me, my car is 91 and ran a orange ecu on a auto box...

I am converting it back to manual now using parts from a 92 turbo which ran with red colour ecu..

I am going to change my fly wheel to the later type 215mm, And changing my orange ecu's for a pair of red ecu's and also fitted the maf so i know every thing will go together as it all came off the same vehicle..

Question is will it run ? when you look at the old auto tdc sensor cut out on the fly wheel it doesent match that on the later type 215 mm its about 5 degrees retarded, but both sensors remain in the same place on either box so the only thing i can think of is the tdc difference must be adjusted via the ecu, Hense why i bought every thing from the donar, paired ecus,flywheeel,clutch the lot....

Help on this would be great as bit's arriving on tuesday