Heavy sttutering and stalling

[iimomar]

Hi!

Some time ago my 480 turbo started showing stuttering at high boost, which was more noticeable at 3 & 4 gears. After some forum search I identified the flywheel sensor as the possible cause of this stuttering. I removed this sensor and cleaned it. After doing this the idle was smoother and I thought “problem solved”, but it wasn’t… after driving the car for I a while the stutter was too much hard, with too much I mean very very hard, in fact I think that the engine directly stops running. I thought that the problem was a defective sensor and I have recently replaced it, but exactly the same symptoms as before…

Now it is almost impossible to ride the car, the only way it’s to use a very little fuel pedal, but if I have to climb a slope the engine stalls and stops… last day I had to come back home in reverse gear to climb a light slope… (I’m not joking).

I hope that someone can give me some clues about what could be happening…

Thanks!

Thanks!

[jamesy12345]

Looking at your old posts it would be a good idea to try another Jetronic ECU, unless you are sure it is OK

[iimomar]

Thaks for your answer. I have an spare ECU, so I'll check.

[jamesy12345]

Which colour of ECUs do you have Iimomar? For example on some of the later turbo cars the EZ210K ECU should be blue and the Jetronic green.

[iimomar]

Purple EZ210k and orange jetronic. It's an 1989 non cat turbo.

[jamesy12345]

Like this I guess then....



With Jetronic ECU 430 905

info from here http://www.freewebs.com/hjkort/480ecus.htm

[iimomar]

Yes exactly, that ones are. I've been just now checking both ECUs, I've exchanged them with a spare, but... same engine behaviour...

Clues are welcome.

[sparkysparks]

Mine does this sometimes aswell.
It did it more so when i messed with the resistance on the maf.
Its not done it for a while now though.

[jamesy12345]

It's good that you were able to check that quickly!

See link below...these guys talk about similar problems - octane rating of fuel is mentioned and HT components of the ignition with the coil as the favourite

http://www.volvo-480-europe.org/forum/v ... 11&t=14741

Sorry I am just guessing, I haven't had this on any of my cars, just trying to give ideas!!

[iimomar]

Hi again,

Following your advices I checked the MAF yesterday but with no results…this is not the source of the trouble… L. The HT leads and the distributor are relatively new and they are in good order, thus, the only thing that could be causing the problems would be the ignition coil??¿?. I don’t know if a defective coil can cause such a heavy stalling under such light engine load… Anyway, is there any way to check if the coil is ok without replacing it?

Again, any new clue will be welcome!

[jamesy12345]

Hi, the thread I posted above did mention the coil. You can check resistance or use a test lamp on the low voltage side but not always easy to tell a good one if it is marginal.

Did the stuttering start just after fitting new leads and cap...?

[iimomar]

The distributor and leads were changed at different times. After renewing the distributor cap, the behaviour of the engine was smoother and it didn't cause any kind of stutter at all. The HT leads were renewed later (magnecor ones), I'm not 100% sure of if after this replacement induced a bit of stuttering... but I'm quite sure that the stuttering started before. In any case, the stutter/stalling that I feel now it's too much hard that the previous one.

I hope this can provide some useful information...

A doubt that I have is: why at a minimum load in 1st gear the engine stalls, but it doesn't in reverse gear?

[jamesy12345]

Worth a look at that coil....best way is to try an known good one. The same goes for the leads too - if you still have the old ones give them a go.

Where are you based by the way? And does the diagnostic system on your car work?

[iimomar]

Ok, I'll check and see...

I'm based in Spain, I'm afraid but my 480 doesn't has the diagnosys system. I think it was installed in the later versions.

I'll keep you updated.

[iimomar]

Well, after some holiday days, yesterday I could check the ignition coil. I exchanged it for a while with a one in good order, but the car exhibit exactly the same symptoms as before. The car continues stalling under the minimum engine load...

I'm starting to be tired of this car, all in it is prone to fail, and I'm seriously considering breaking it.

If anyone has any clue... please let me know... Bear in mind that your help could help to safe the live of a 480...

Thanks!

[jamesy12345]

This is a hard one!!

Sorry my ideas came to nothing

[jamesy12345]

more possibly incorrect ideas!!

http://www.volvo-480-europe.org/volvo48 ... ine_stalls

[iimomar]

I've been thinking about what the hell could be causing the stall of the engine... And... could be related with a lack of fuel pressure? Either due to a faulty fuel pump or a fuel pressure regulator? If yes, how can I check it? Which should be the fuel pressure at the injection rail?.

[Robou]

For a starter, the ECU's do not match. If the chassis number is below 540197 the EZ should be purple and the matching Jetronic brown. This is related to the camshaft which was changed.
And because things were messed up here, check the MAF. There are two types, I believe type # ending with 007 and 021 respectively. Using the wrong MAF and/or bad connection will cause the problems as described.

[iimomar]

The chassis is below 540197, and the Ecu's are EZ210K: Purple 0227400125, and LH2.2: brown 0280000551, and the MAF ref. is 0280212007. What I don't understand it's why you say that do not match, the pic posted above is exactly of these ECU's...