C55 gone bonkers

[brucemillar]

Help please: c55 W203 2004.

Occasionally when you put it into gear (D) or (R) in any mode. It starts to blip the throttle. This is a rythmic blipping and requires foot on brake to hold the car. It will eventually stop as you reach about 20mph but then stalls the engine if you brake hard to a standstill. Switch off ignition then on and it is fine.

The blipping is almost software driven AKA F1 cars having their warm up from a PC.

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[TDE1]

Didn't want to read and run so..

Not sure if it compares, but mine (E55k) started hunting all over the place about a year after I bought it. Afraid it required a new throttle body. Is your EML on when it happens?

Hope yours is an easier fix

Tim

 

[brucemillar]

Tim

Thank you. No EML light on and no dash errors.

I think it significant that the car will start and idle absolutely fine. It is only when you move to D or R with foot still on brake pedal that the blipping starts?

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[french]

Have you checked your Idle Air Control Valve ?

 

[nb_racing]

throttle body, or air leak between throttle butterfly and engine.

 

[brucemillar]

Have you checked your Idle Air Control Valve ?

Where is this located please? Any clues what it looks like.

Many thanks.

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[french]

On the TB , also check the small bore vacuum pipes around the TB are not lose or split. Unmetered air into the engine can cause high idle, rough idle, etc.

HTH

 

[vealige]

Mine stalled once or twice when up to temp was a nackered crank sensor fiddly to replace as there is sod all room but cured my stalling problem. I had no hunting issues.

 

[unit504]

if its not the MAF, Throttle Body (expensive), crank sensor, air leak etc...
have you thought about the accelerator pedal..? theres a module there.. if the voltages are not right can cause issues and throw up MAF sensor errors...

 

[Sarim@MSL]

If it idles fine, sounds like a Torque Conveter issue, as if its always engaged, makes sense that it makes the car 'jump' and then it stalls if you put your foor on brake?

 

[brucemillar]

All

My apologies for not responding sooner. I found the answer when I got smoke and burning oil smell in the cabin.

Turned out that the engine oil filler cap was incorrectly fitted allowing a fine mist of oil to escape. I can only guess that this also caused some pressure issue? When the cap was properly fitted and my blushes has stopped, the problem had gone and remains gone.

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