ML270cdi (2001) Low Rev problems

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Last month my Mercedes ML 270cdi began driving only at low revs in emergency mode, when taken to my mechanic he had replaced the intake manifold.

After about a week, I have been experiencing similar problems but the car now goes into this emergency mode intermittently. Some days the car is fine, other days a pain.

Anyone having or had similar problems??? Please help.

 

[oigle]

Last month my Mercedes ML 270cdi began driving only at low revs in emergency mode, when taken to my mechanic he had replaced the intake manifold.

After about a week, I have been experiencing similar problems but the car now goes into this emergency mode intermittently. Some days the car is fine, other days a pain.

Anyone having or had similar problems??? Please help.

Perhaps the EGR is sticking a bit occasionally or maybe the MAF is acting up.

 

[BlackC55]

What fault codes?

 

[tony jr]

I would get the fault codes read to try and pin point the problem - could be several things.

I recently had a similar problem and had to replace the inlet manifold and inlet port motor (that shuts the flaps in the inlet manifold) - Did your mechanic replace the inlet port motor when he changed the manifold?

It could be a MAF sensor problem - similar symptoms

I was also told that battery problems resulting in slightly lower voltage can cause the gearbox to put the car in limp mode

 

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inlet manifold, fuel filter, maf sensor and the flap motor for the manifold was replaced. Nothing comes up on the diagnostic test at all, had car tested twice. Problem is intermittent, arises on average every other day.

Its frustrating because while i'm anxious about more big bills just annoyed because i dont know whats wrong with the car.

 

[Alex Crow]

if it was in 'emergency mode' as you say there WILL be fault codes - does your garage have a 'star' machine??

 

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I think in time i'll have to change mechanic as slowly losing confidence in the one i'm using. I'll be finding out whether any mechs use this star machine (thanks for that tip).

Question, its been on diagnostic twice but no results have come back. As the problem is intermittent would the fault codes only come up when the car is in emergency mode???
The last time i took it in he said car was running fine with no problems and no codes came up but that was just because the car wasnt playing up.

Is it just a matter of waiting until car is playing up then trying to get it tested when the problem is occuring.

 

[Alex Crow]

fault codes, once logged, will remain in the memory indefinitely - as i said if it goes into ANY one of the various 'limp home' strategies it WILL log fault codes.

 

[traffic]

Thanks for the reply Alex. Much appreciated.

What I'm going to do is try a different mechanic and start again fresh. I know theres a problem but this guy keeps on telling me the car is fine. I'm going to find a merc specialist, one with the star machine and hopefully get to the route of the problem.

I'll try and post something in a few days and update.