Mercedes Benz E-Class W124 (1985 - 2000) - ' 91 230TE won't run when warmed up

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Tue 1 Jan 2008 16:20
' 91 230TE won't run when warmed up - dodo
Sucumbing to a long desired dream to own a 'classic'W124 estate I recently bought a beautiful J reg 230TE. It has been a joy to drive and a nice change from the 21st century euroboxes. However it has recently started to stutter and eventually stop altogether once it has reached normal operating temperature. Notwithstanding the problem of breaking down on the road it will not start again until cold! I have checked plugs etc - power still coming and fuel pump seems to be working. Any idea what the problem might be and how I could fix it? Cheers and Happy New Year!

Edited by Pugugly {P} on 01/01/2008 at 16:31

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Tue 1 Jan 2008 16:35
1991 Mercedes 230TE won't run when warmed up - Screwloose
dodo

This sounds as though it's either losing a spark, or seriously over-fuelling. Remove and check the cold-start injector for leakage and the engine control relay [behind the battery?] for corrosion.

The main fuelling sensors are the coolant temp sensor and the vane position sensor on the metering unit. The actual adjustment is done by the fuel pressure control solenoid.

There are primitive fault codes available if you have access to an oscilloscope.
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Tue 1 Jan 2008 17:06
1991 Mercedes 230TE won't run when warmed up - Aprilia
If you definitely have sparks then its a fuelling issue. It could be the EHA, the pot on the VAF meter, the idle control valve, throttle switch. One quick check is to take a look at all the air hoses and check that they have not cracked with age - particularly the hose that enters the air meter body fight underneath (you can't see it, you have to feel for it).
In theory the system should run with the EHA disconnected, also disconnect the cold start injector - see if that helps.

If none of that works then take it somewhere that understands these systems (Bosch KE-3.5) and get them to hook up pressure gauges etc. - much quicker in the long run than 'poke and hope'...
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Tue 1 Jan 2008 19:24
1991 Mercedes 230TE won't run when warmed up - dodo
Have tried spark and yes is working, car now sitting outside and cold -and still won't start. Will see in the morning. I genuinely think its not big problem but boy is it annoying.
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Tue 1 Jan 2008 20:34
1991 Mercedes 230TE won't run when warmed up - Aprilia
Well, check out the overvoltage relay and make sure that the fuel pump runs (runs to prime on turning key, then runs once gets rpm signal).
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Tue 1 Jan 2008 20:43
1991 Mercedes 230TE won't run when warmed up - elekie&a/c doctor
The Bosch KE jetronic system on these is very reliable.However is is very important to have the correct fuel pressure or the system goes to pot. Check carefully under the rear of the vehicle as some of these 124 models have 2 fuel pumps,one is located under rear floor behind a plastic cover and a a second attached to a bracket near the rear axle.If one pump fails,then the car will not run correctly.hth
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Tue 1 Jan 2008 21:00
1991 Mercedes 230TE won't run when warmed up - Aprilia
If this is a '91 model then surely it only has one pump doesn't it (under the plastic cover)?

Right about the pressure though. Probably best to have someone put gauges on it and check it out anyway....Then put on new filter, clean up sensor plate etc etc and generally fettle it up.
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Tue 1 Jan 2008 21:11
1991 Mercedes 230TE won't run when warmed up - elekie&a/c doctor
for some reason the TE estate model has second pump attached to back axle in a rubberised insulation/casing assy.May be due to design/space under rear floor?
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