Running On

All the information you need on engine-problems is here. The engine includes the Turbo-charger, airco and everything else you'll find under the bonnet.

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jamescarruthers
480 Is my middle name
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Location: Cambridge

Running On

Post by jamescarruthers » Thu Feb 21, 2019 9:52 am

Believe it or not both launch cars are suffering from the same problem here. When hot, the engine runs on after you switch it off. Keith's car did this over ten years ago when I owned and still does it. Mine has done it before and after the engine rebuild.‎

All I can think of if a leaky injector. However, mine have been out, tested and cleaned.‎

I've read a little on-line and it suggests that the wrong temperature spark plugs can cause the chamber to be so hot that fuel ignites on its own. ‎There has been some talk of spark plug manufacturers getting our engines confused.

I have bought some Champion ‎RN9YC to replace the ‎NGK ZGR5B (I think)‎ that I have installed but won't be able to fit those for a few weeks while I'm away.

And other ideas to consider until I get the spark plugs?‎
1987 Volvo 480 ES, 507274, 217 - Red
1992 Renault Master Mk. 1. Machzone Chateau camper. 2.0 LPG

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo
E981 KHM -- ES (509849)

Alan 480
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Location: Aberdeen

Re: Running On

Post by Alan 480 » Thu Feb 21, 2019 12:47 pm

James
whilst teaching grannies to suck eggs. . . . . .
you need three things for combustion, air, fuel & spark

OLD carb fed cars would 'run-on' cos the idle was set by a fixed butterfly opening and this let air in, obviously as the air went in it sucked in fuel.

if the plugs were 'redders' then it would 'diesel' for a short time (a few seconds) or if really 'shagged' it would pull up oil from the sump and this becomes REALLY interesting to shut down on an old large diesel :shock:

to prevent this (on old carb fed) there would be a 'fuel cut-off' valve fitted to starve it of fuel, so it only had two out of three legs.

now in your case the fuel SHOULD be shut off with injectors so swapping plugs will make no real odds??

so it sounds as if there is a wee dribble of fuel passing/sitting in the inlet manifold?

there will always be a small opening in the idle passage, either butterfly not fully closed. or through the idle valves 'stationary stop position'

only a thought :D
Alan

480 ES 2litre, C30 1.8ES, SS1 + more

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jamescarruthers
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Location: Cambridge

Re: Running On

Post by jamescarruthers » Thu Feb 21, 2019 1:29 pm

Hi Alan, all input gratefully received!

I agree that the car 'should' completely ‎shut off the fuel supply when the ignition is off but somehow it is getting all three things (fuel, ignition, oxygen).‎

When starting, if the crank sensor detects the engine turning, it switches the fuel pump on. On shut down, I don't know if it should do this when the key is out but some how the engine runs on. I am wondering if the combustion chamber is so crazy hot from the wrong plugs that it ignites the remaining fuel enough for one more revolution, which the crank sensor sees and then keeps feeding fuel in. Alternatively, it could maybe using what is in the line. 

My first thought was that the fuel pressure regulator was leaking fuel in. I have a brand new on installed and this didn't help. The only thing that I've found odd on this early engine is that it doesn't have a fuel pulsation damper. I don't know whether adding one would help or not or whether or not keith's car has one. I should ask him really. ‎

It isn't too bad to access the injectors one more time but I don't fancy it if I don't have to. Maybe I have been unlucky and they are indeed leaking in to the combustion chamber.‎

I have become practised in the art of stalling when switching it off and then running to the engine bay. It doesn't smell of fuel but that's not the greatest test for a leak.

Other than this the car goes like stink and I have no complaints with its engine.‎
1987 Volvo 480 ES, 507274, 217 - Red
1992 Renault Master Mk. 1. Machzone Chateau camper. 2.0 LPG

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo
E981 KHM -- ES (509849)

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jamescarruthers
480 Is my middle name
Posts: 1464
Joined: Mon Jul 07, 2003 3:19 pm
Location: Cambridge

Re: Running On

Post by jamescarruthers » Thu Feb 21, 2019 1:34 pm

On a side note, I had the turbo seals fail on my old Citroen XM 2.1‎SED diesel and it ran on and was basically about to destroy itself with diesel runaway. Thankfully I sort of thought this might be going to happen to the old girl as it had been behaving funny for a while. While fiddling about in the engine bay it did it and I managed to run from engine bay to driver's seat and dump the clutch. I have never moved so fast in my life, ever! 

A second or two later I assume it would have just eaten the clutch and ran away to its death... I consider myself very lucky to have caught it in time.‎ I have no idea what RPM it got to in a few seconds but it didn't seem to have any lasting damage.‎ It got a new turbo and pipes and then seemed to behave very well. ‎
1987 Volvo 480 ES, 507274, 217 - Red
1992 Renault Master Mk. 1. Machzone Chateau camper. 2.0 LPG

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo
E981 KHM -- ES (509849)

Alan 480
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Location: Aberdeen

Re: Running On

Post by Alan 480 » Thu Feb 21, 2019 6:35 pm

jamescarruthers wrote:
Thu Feb 21, 2019 1:34 pm
On a side note, I had the turbo seals fail on my old Citroen XM 2.1‎SED diesel and.........‎ It got a new turbo and pipes and then seemed to behave very well. ‎
oh yes forgot about that way of feeding a diesel with fuel!!! :D

bet you that was a 'brown trousers moment' ? :lol:
Alan

480 ES 2litre, C30 1.8ES, SS1 + more

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Jay-Kay-Em
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Re: Running On

Post by Jay-Kay-Em » Thu Feb 21, 2019 8:12 pm

I was always taught carbon glowing cherry red, wrong temp plugs or a petrol engine 'dieseling' on its oil (poor oil control rings etc).

But, if you say its a rebuilt engine, that eliminates two of those!

I've had a few carb cars run-on, but never an EFI. When injectors dribble they tend to do just that - dribble - and not atomise.

Its not something sticking on like the ignition barrel or a relay somewhere? I had a strange fault on the TVR where the headlamps would always stay on for 10 seconds after you'd turn them off... like some sort of courtesy delay. It got worse and worse, for longer and longer, until one day, they wouldn't switch off at all. It was a furred up pair of contacts in a relay sticking. I took the plastic body off, cleaned the internal switch contacts, just fine. Just thinking if any part of the ignition is relay controlled, it might be hanging for a few seconds...

Just thinking outside the box as you seem to have all the bases covered.

Alan 480
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Location: Aberdeen

Re: Running On

Post by Alan 480 » Fri Feb 22, 2019 12:56 pm

do petrol injectors really 'inject' I thought they just dribbled the fuel into the inlet tract (OK a sort of spray, but not a proper diesel spray) :-)

i wondered about pulling off the wire from the ignition pack rather than turning the key off, that should stop engine pretty quick, if it runs on then it must be the plugs?

ditto the fuel pump supply, I know that loss of power to the pump on ours is instant cut-off.. . ..
Alan

480 ES 2litre, C30 1.8ES, SS1 + more

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jamescarruthers
480 Is my middle name
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Re: Running On

Post by jamescarruthers » Fri Feb 22, 2019 1:28 pm

Alan 480 wrote:
Fri Feb 22, 2019 12:56 pm
do petrol injectors really 'inject' I thought they just dribbled the fuel into the inlet tract (OK a sort of spray, but not a proper diesel spray) :-)

i wondered about pulling off the wire from the ignition pack rather than turning the key off, that should stop engine pretty quick, if it runs on then it must be the plugs?

ditto the fuel pump supply, I know that loss of power to the pump on ours is instant cut-off.. . ..
That's a good call on pulling the king lead and fuel pump power to eliminate any spark from the plugs and any fuel from the pump (line pressure will get through I guess if the injectors are leaking). 

The injectors spray, properly, individually and directly into each cylinder. I think what you are talking about is single point or mono point fuel injection. 

I will ‎do the two pulls separately when I am next with the car. Cheers Alan. 
1987 Volvo 480 ES, 507274, 217 - Red
1992 Renault Master Mk. 1. Machzone Chateau camper. 2.0 LPG

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo
E981 KHM -- ES (509849)

eye of ra
Can tell where the 480 was built
Posts: 351
Joined: Tue Dec 04, 2012 7:33 pm

Re: Running On

Post by eye of ra » Sun Feb 24, 2019 12:27 pm

jamescarruthers wrote:
Fri Feb 22, 2019 1:28 pm
The injectors spray, properly, individually and directly into each cylinder.
That is not actually true. Our cars use Multi-Point Injection not Direct Injection.

This is something I have been meaning to look into properly but have not gotten round to ever since finding out that the injectors fire into the inlet manifold not the cylinder and fire in PAIRS!!! not individually.

Here is brief explanation of the different types I have just found

https://www.cars.com/articles/what-are- ... 690418419/

Note the explanation in Sequential Fuel Injection about Multi-Point.
Current:
480 ES Auto 1989
480 ES Auto 1991
CLK430 Conv 2001
Hyundai i10 2015

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jamescarruthers
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Re: Running On

Post by jamescarruthers » Sun Feb 24, 2019 5:04 pm

eye of ra wrote:
Sun Feb 24, 2019 12:27 pm
jamescarruthers wrote:
Fri Feb 22, 2019 1:28 pm
The injectors spray, properly, individually and directly into each cylinder.
That is not actually true. Our cars use Multi-Point Injection not Direct Injection.

This is something I have been meaning to look into properly but have not gotten round to ever since finding out that the injectors fire into the inlet manifold not the cylinder and fire in PAIRS!!! not individually.

Here is brief explanation of the different types I have just found

https://www.cars.com/articles/what-are- ... 690418419/

Note the explanation in Sequential Fuel Injection about Multi-Point.
Thanks for the clarification. I hadn't paid much attention to where the fuel was going, I just saw it going four separate places and assumed to each cylinder. It certainly isn't going in to the manifold early like a carb. or monopoint but looks rather in to each cylinder's  separate inlet manifold

I think the early cars with Fenix 1 B18E and later ones fire in different ways. I don't have my books to check but is it true that the B18E fires in pairs and everything else fires together or something like that?

I'm determined to not turn up at the May meet having to stall the car at each stop sounding like an old banger!‎
1987 Volvo 480 ES, 507274, 217 - Red
1992 Renault Master Mk. 1. Machzone Chateau camper. 2.0 LPG

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo
E981 KHM -- ES (509849)

jifflemon
480 Veteran
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Re: Running On

Post by jifflemon » Sun Feb 24, 2019 5:19 pm

Just a quick question James, how Long does it run on for? Seconds? Hours?

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jamescarruthers
480 Is my middle name
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Location: Cambridge

Re: Running On

Post by jamescarruthers » Sun Feb 24, 2019 5:33 pm

It varies. Sometimes it will just do one revolution, other times four or five, but I normally just dump the clutch at this point. I think I let it carry on once or twice and it seemed like i‎t was never going to stop!

It is very much temperature dependant and it will not do it unless the engine is at working temperature. It takes a while to start afterwards if I let it chug away, implying it has used the fuel from the line but the pump hasn't provided it.‎
1987 Volvo 480 ES, 507274, 217 - Red
1992 Renault Master Mk. 1. Machzone Chateau camper. 2.0 LPG

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo
E981 KHM -- ES (509849)

eye of ra
Can tell where the 480 was built
Posts: 351
Joined: Tue Dec 04, 2012 7:33 pm

Re: Running On

Post by eye of ra » Sun Feb 24, 2019 6:27 pm

On Multi-Point the injector fires into the inlet manifold just before the valve, as you say not as far back as Carb or Single-Point but not straight into the cylinder like Direct.
jamescarruthers wrote:
Sun Feb 24, 2019 5:04 pm
I think the early cars with Fenix 1 B18E and later ones fire in different ways.
Very good point.

So I checked my books and was even more surprised with what I found.

18E fires in 2 pairs.

18F, 18EP, 18FP, 18FT and 20F appear to fire all 4 at the same time. :eek:

More investigation required.
Current:
480 ES Auto 1989
480 ES Auto 1991
CLK430 Conv 2001
Hyundai i10 2015

User avatar
jamescarruthers
480 Is my middle name
Posts: 1464
Joined: Mon Jul 07, 2003 3:19 pm
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Re: Running On

Post by jamescarruthers » Sun Feb 24, 2019 6:55 pm

This is because the B18E rocks!
Last edited by jamescarruthers on Mon Feb 25, 2019 4:39 am, edited 1 time in total.
1987 Volvo 480 ES, 507274, 217 - Red
1992 Renault Master Mk. 1. Machzone Chateau camper. 2.0 LPG

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo
E981 KHM -- ES (509849)

Robou
Knows an Aerodeck isn't a 480
Posts: 252
Joined: Sun Jul 08, 2007 11:34 pm

Re: Running On

Post by Robou » Sun Feb 24, 2019 11:27 pm

Very intriguing! The "dieseling" needs fuel. Injection being multi point or "semi" multi point shouldn't matter, it is activated in some way. Now when the ignition is switched off it is only effective as far as the spark is concerned, because the ignition coil is effectively powered off. But the ECU isn't, if it were only for controlling the auxiliary waterpump in some cases. During "dieseling" it gets all the signals as from a normally running engine. Why would't it activate the injectors? There is still some pressure in the fuel line.
Well, they may be activated, but to no avail. The injectors are pulled to ground by the ECU so they need to be connected to power to open. Power is supplied by the fuelpump relais of which the activation is interrupted at ignition off. This leaves only one possibility: The relais is defective and doesn't open. This means also the fuel pump is running.
In later years, from 1991, the situation differs. Of course.

In order to prevent this phenomenon, caused by glowing carbon residues in the cumbustion chambers, use colder plugs like NGK BPR8ES or -7ES and make a long fast drive. The residues may be blown away, through the exhaust that is.
Too old to bother
480 Turbo midst '91

eye of ra
Can tell where the 480 was built
Posts: 351
Joined: Tue Dec 04, 2012 7:33 pm

Re: Running On

Post by eye of ra » Mon Feb 25, 2019 12:28 pm

Was thinking along the same lines as Robou, how the Multi-Point/Sequential/Batch/Port Injection system actually works is not really relevant to your problem (I’m still curious though).

So unless the injectors are leaking Robou is correct they must be getting power to fire and on the Fenix 1 this could be from either of the relays under the dash sticking as they are connected in tandem (changes on Fenix 3.2 and later) or don’t know if its mechanically possible but the key switch maybe another possibility, if your Heated Seats are still working during run-on the key switch is still supplying power.
Current:
480 ES Auto 1989
480 ES Auto 1991
CLK430 Conv 2001
Hyundai i10 2015

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