Worse performance after servicing

[Horrgakx]

My 1999 E55 AMG W210 was serviced recently - big service entailing all 16 spark plugs, 2x engine air filters, fuel filter, oils, etc, etc... But when I picked it up I thought it lacked pulling power in the low rev range.

After driving it for a couple of weeks since the service I still think that the performance is below par at lower revs. It's probably most noticeable when the car changes up gently from 1st into 2nd and I push the pedal all the way down. Once it hits about 3,500-4,000 rpm there's a change in performance and it will pull very strongly all the way to the redline.

Worth saying that there's no perceptible 'coughing', missing or anything else I can detect.

Any comments on this please?


Ta.

 

[rees_A]

Could it be your MAF failing? Mine was similar to yours until it was changed...

 

[Horrgakx]

Don't tell me - it's only possible to diagnose by plugging into an MB computer thinggie?
(and does it have 2x of them?)

 

[BlackC55]

Only one MAF and a start will show up "self adaptation" faults if a problem is present.

 

[Horrgakx]

Nothing on the display...

 

[BlackC55]

I ment on a Star diag machine.

 

[kwakdonut]

Unplug the MAF and drive the car. If there is a difference (ie, runs better) then it could certainly be the problem. Get it on STAR anyway as this may well show up other possible faults.

 

[Horrgakx]

Thanks, will do, any pics as to where to locate them?

 

[kwakdonut]

The MAF will be located somewhere off the air filter. As yours has two, I assume there is a connecting pipe? It should be fairly obvious and will have 1/2 electrical connections (my 320 has 2 connectors and sits between air filter and turbo)

 

[andy27168]

Hi,
The MAF is situated under the main air box on a 55, its where the airbox connects to the engine though i believe it has only one connector.

 

[AndyPCD]

The therhing to check is that the air filter housing has been fully fitted home on top of the MAF sensor.

If it hasnt been pushed all the way home it has a tendency to lift up

 

[Horrgakx]

Thanks will check.

 

[mr. shr]

My 1999 E55 AMG W210 was serviced recently - big service entailing all 16 spark plugs, 2x engine air filters, fuel filter, oils, etc, etc... But when I picked it up I thought it lacked pulling power in the low rev range.

After driving it for a couple of weeks since the service I still think that the performance is below par at lower revs. It's probably most noticeable when the car changes up gently from 1st into 2nd and I push the pedal all the way down. Once it hits about 3,500-4,000 rpm there's a change in performance and it will pull very strongly all the way to the redline.

Worth saying that there's no perceptible 'coughing', missing or anything else I can detect.

Any comments on this please?


Ta.

Not something silly like the box is in 'W' mode instead of 'S' ??

(Long shot I know, but worth checking.)

 

[Horrgakx]

Good thinking, and I had this issue with the stuck switch. In this case not the solution.