E220TE Cold Running Problem

[deejaybee]

Have recently aquired a '93 E220TE. It has ''only'' done 120K miles and is in quite good shape for the price I paid.

When I bought the car it had the ''hunting'' problem which seems common with these. After changing the oil, filters, plugs and cleaning the MAF and throttle body this seemed to cure the hunting problem but then the idle speed increased up to about 1100rpm. I found that the throttle cable adjuster had been screwed right out (presume to stop it stalling) and I re-adjusted this to what semed a more reasonable level.

Currently the idle speed when warm is about 800rpm in N/P and drops to about 600rpm in D. Also it starts on the key when cold and idles at about 1200rpm (which I think is right), but it quickly drops after about 10-20 seconds and will stop unless you give it throttle. This means the car is difficult to drive straight away unless you let the engine run for about 1-2 minutes keeping the revs up with the throttle. Once it has warmed up a bit it is fine, even through the revs drop right down to 500rpm in D until it has thoroughly warmed up.

This presumeably must just be some aspect of cold running control? But not sure if this would be ECU related or anything else. Any advise would be appreciated.

regards,

Dave

 

[television]

Hi Dave, I do not know if you have solved your problem.

Your car is motronic. the sensors are critical, that is the air temp and water temp. You have an enrichment device operated by the key, if a sensor gives the wrong infor this cant be engaged from a cold start up

 

[deejaybee]

Cold running problem still present

Malcolm,
thanks for your reply. I still have the problem. Is it possible to work through the sensors and check / replace these without diagnostic equipment (I have a multimeter but nothing more sophisticated), or do you think this is a job for the garage?

Thanks,

Dave

 

[Bolide]

Most problems with 220s seem to be related to the throttle body. Assuming the temp sensor is OK I'd try a good secondhand throttle body if you can find one at a reasonable price. It may need to be setup on a Star machine - not sure

You are bound to have an independent with a Star machine nearby. I'd ask them for a diagnosis but before asking any garage to fault-find it properly I'd want to be sure they know what they're doing

Nick Froome
www.w124.co.uk

 

[television]

One thing you can test is the sensors with your meter,,they are normally around 4.7kΩ when cold at 20c and drop down to near zero when hot

These are approx values

 

[deejaybee]

Still having cold start problems

I have recently replaced the air inlet temperature sensor as this was easy to get at and relatively cheap, also the OVP relay has been replaced with a a new genuine item.

I have not replaced the water temp sensor as it is not very easy to get at, but also I believe that it is the same sensor for the temp gauge and the motronic (is that right?) and the temp gauge is working fine.

When cold engine starts fine but literally runs for a few seconds and then dies unless you put your foot on the throttle. It runs ok when warm.

I have seen some threads which talk about a microswitch on the throttle body that triggers the higher rev setting for cold running - could this be the problem? I can see the black plastic housing on the side of the throttle body which presumabley has this in although I can't actually see any wires going into it?

Only other aspects I have seen on here relate to the EGR valve and cold start valve - not sure if it could be these.

I believe the MAF is working OK, it is certainly doing something because the engine stops if it is disconnected.

Any help appreciated.

Dave

 

[jimsplatt]

I have the same cold start problem - fires straight up, then dies almost immediately. It also idles very badly until it is warm, stalling frequently. Did you solve the problem in the end?

 

[deejaybee]

cold start problem still there

No, unfortunately I haven't solved the problem yet. It is not as bad now the weather is getting warmer, but it is still there.

I had a look inside the throttle body last weekend and the mechanism does seem to be working properly. When starting from cold the throttle is opened and then the stepper motor gradually closes the throttle. Only thing is it either closes to quickly sometime when cold or sometimes seems to hunt rapidly as it approaches normal tickover, causing a rapid clicking noise (but the engine doesn't necessarily stop).

On my car I do suspect that I have a duff Lamda sensor which could well be affecting this? I am going to try and replace this and see if it cures the problem, otherwise I am not really sure what the problem is. As soon as the engine has warmed up a bit / is hot there are no obvious running problems such as stalling at junctions etc.

If anyone has any further ideas about this problem I will be pleased to hear them.

 

[jimsplatt]

My problem seems to have cleared itself (touch wood). I put a bottle of redex injector cleaner through the fuel system, took it on a long run to the coast and eventually it sorted itself. I don't know if the redex was the cure, or whether the long run helped, but it seems fine now. Mine is a complicated case, though - I have an LPG system on my car, which means I don't use petrol that much. Might it be that the cold start injector had got clogged? I don't know. It might be worth a bottle of redex or similar, though...

 

[deejaybee]

My cold starting problem has also been ''solved'' - the car got nicked last week!!!

Not sure if I am going to replace it with another 220 or a 300 diesel, it depends what comes up.