e320cdi power problem

[benzino]

Hi all

i encountered a problem on my e320cdi 2000 today. seems to accelerate normally from standstill to about 30mph but just before 40mph acceleration pretty much stops and slowly goes to about 50mph and then gradually picks up again but not amazing. even pressing full throttle doesnt do anything.

when car is running in idle, revving and holding throttle only goes up to three revs and then starts shaking and doesnt go further.

no fault codes

any ideas peeps

 

[compress ignite]

Fuel filter(s)

see above

Algae

 

[BlackC55]

Air mass is the first port of call. (make sure air filter is clean)

 

[television]

As BlackC55 above MAF

 

[Dunhamkid]

As above, I had the same symptons

 

[benzino]

thanks all for the initial advice

as mentioned the problem started yesterday but for a while today car was back to normal. Then, stopped by at a garage so switched it off, switched it back on and then problems again. Then again, by the time i got home it was ok again, revved it up after parking and revs went booming over 3k up to red. switched off engine, then switched on again and revs back to stopping at 3k, took it out again and was sluggish once more.

any further suggestions?/confirmation of MAF?

 

[television]

thanks all for the initial advice

as mentioned the problem started yesterday but for a while today car was back to normal. Then, stopped by at a garage so switched it off, switched it back on and then problems again. Then again, by the time i got home it was ok again, revved it up after parking and revs went booming over 3k up to red. switched off engine, then switched on again and revs back to stopping at 3k, took it out again and was sluggish once more.

any further suggestions?/confirmation of MAF?

Yes, unplug the MAF, the car will run, but rather rough but should be better

 

[vanisle]

cdi problem

change your two fuel filters and add cleaner to fuel.
I keep spairs in the trunk at all times.
clean out air box & replace air filter

 

[benzino]

hey thanks

the fuel filter on my car has not been changed for at least the last 80kmiles. i am due to have it done this weekend. is there two or just the one? and how do you add cleaner to the fuel?

btw how do you know these may be the problems? have you had similar problems? could it still be MAF?

Riz

 

[benzino]

Hello all

i had kind of got used to not having the power under my foot as mentioned below and the car would not go above 3000revs in idle.

then today i thought id take it for a spin just to give a good run because short journeys in the cold hardly make the temp go above 40.

car seemed to be fine, accelerating brilliantly of roundabouts. then i thought ill let the speed drop down to about 30-40 and then try full kickdown. as soon as did that the car went heavy and went back to how it was the last few days.

as opposed to things like the fuel/air filters or transmission fluid, i am definitely thinking this is more electrical now. faulty MAF, Fuel switch relay, kickdown switch???

can anyone help me narrow down to one out of the above, or are there any other things to consider

 

[evdok]

Faulty injectors? maybe worth checking plugs & wires sounds like loose wiring of some kind.

 

[television]

We have already narrowed it down to the MAF, unplug it and try it

 

[DrNick]

I thought that most Mercs were limited in how high they will rev whilst idling? IIRC its about 3000rpm, so revving whilst at a standstill is not going to prove much?

 

[scgfull]

This sounds very - very similar to a problem I had. It was found to be 'sludge' in the bottom of the fuel filter bowl. It had probably come from the tanks of the filling station.

To check this is simple and no cost so I would strongly recommend, before doing any thing else more drasti, checking this. Then, as Malcolm says check the MAF and then the fuel rail sensors.

Steve

 

[benzino]

Hi everyone

thanks again for your valued feedback. i managed to get a tech at mercs to have a look at it. he ran the diagnostics and the three major things that came up were:

1) glow plug failure cylinders 1-6. fault status STORED
I have had the car 4yrs and from day 1 the glow plug light in the dash would stay on for about 10secs after starting and then would go off. never had any other starting problems etc. So i guess this wouldnt have anything to do with the acceleration problem???

2) B2/5 (Hot film mass air flow sensor) The signal voltage is too low
B2/5 (Hot film mass air flow sensor) The signal voltage is too high. fault status CURRENT AND STORED

The tech said to change MAF sensor but when i asked if he was sure that was the cause of the problem he coulfnt guarantee that would solve it

3) The gear is sporadically implausible or the transmission slips sporadically. fault status stored

what do you guys think? is the fault reading (2) conclusive to a faulty MAF sensor.

no other major things came up on the diags. i would unplug MAF and see what happens as Malcolm suggests but really havent a clue what to do and where to look

Another thing not linked to above, Battery voltage 11.85V. is this meaning the battery is ok?

 

[evdok]

Battery is ok, mine reads the same.