Doesn't rev more than 3000ish

[RANA_1]

Hi,

W210 02 plate, 320 CDI Estate.

Just started to experience that the car even when idle will not pass 3000 on rev counter, its as if the limiter has kicked in.

Sometimes around time it struggles to pickup as if the engine is missing.

Drives fine on the mway i.e. no loss of power, changes thru gears smoothly if you press the accel steadily but if you put press the accl hard and then there is no kick down,


Any ideas ?

 

[television]

It will not go past 4k in N

It sounds like MAF problems, just unplug it and see if it is better

 

[jberks]

It will not go past 4k in N

It sounds like MAF problems, just unplug it and see if it is better

4k on the petrols - not tried it on a cdi but I suspect the limiter may cut in earlier - so as Malcolm says - the idle bit is normal.
As for loss of power - again, I'm with Malcolm, start with the most likely culprit - the MAF.

 

[television]

4k on the petrols - not tried it on a cdi but I suspect the limiter may cut in earlier - so as Malcolm says - the idle bit is normal.
As for loss of power - again, I'm with Malcolm, start with the most likely culprit - the MAF.

Sorry Jberks I forgot that diesels fall into a different category

 

[RANA_1]

OK thanks I will give this a go tomorrow.

One other comment is that it does go passed 3K revs when the engine is cold ? I noticed this in the morning, but then as then engine warmed the problem re-occured.

 

[television]

It still sounds fuel related, and can still be the MAF

 

[amb67]

You don't say what kind of mileage you have covered.

It could be that your injectors are dribbling, have you noticed that you get puffs of black smoke out the back when you accelerate hard?

Also, has the fuel filter been replaced recently? Have seen cheap filters cause issues like this, they just won't allow enough fuel flow for these engines.

Hope this helps

 

[RANA_1]

Mileage is 102K
Just serviced last week no faults were reported
I did use to get fair bit of smoke when accel hard, but of late can't do this because of the current issue.
Fuel filter was replaced in october, genuine part.
Hope to have some new tomorrow, could be the injectors already had one replaced !

 

[Cnics]

Slightly OT from this but the CDI's tend to rev to 3000rpm in neutral.

Obviously this probably doesn't have anything to do with your problem and i would check the maf and other things mentioned.

Unless the switch device that limits it to 3000rpm when in neutral is acting up?

 

[bigtwin]

Sounds a bit like what happened to my 320 CDi.

Electrical doohickey went on the turbo system somewhere, and put it into safe mode. Symptoms as you describe.

£120 quids later and all was well again.

 

[RANA_1]

Update at last....

MAF is going to be changed out and then .... there will another....

 

[RANA_1]

MAF Changed - all OK and MPG improved
Hit >43MPG

 

[Kaiman]

Apologies. Im too late. Glad you fixed it.

 

[Kaiman]

Apologies. Im too late. Glad you fixed it.