Intermittent lack of ooomph

[robbi-wan]

Hi all,
I have been having trouble over the last 2 weeks with boost pressure.
Initially, it seemed to be temperature related. When the car was cold - turbo pressure seemed to be ok, but then all of the GO would errrr go (after being pushed); leaving merely diesel power (ie felt like no turbo).
The turbo could be heard to spin/whine but there was no whistle.
So, following Parrotts excellent "how to clean a MAF", i have this morning stripped out all piping to turbo/maf ect and liberally cleaned with squirty alcohol and been for a drive to test (turned out it was not that dirty - what harm could it do?)
The turbo whistle can now be heard but there is no real improvement in performance.
Is there anything relatively simple that it could be post turbo??

There is a pipe from just before the turbo with an electrical connection (thermistor?) to the engine - does this just pull off engine end for cleaning??

There have been no error messages on screen, and it will get upto speed, although not nearly as quick as it should.

Any ideas??
Thanks in advance
rob

 

[Yeti]

I have the same problem with my Sprinter 312D - looks like the needle movement sensor in my case. (I have a MAP sensor, not a MAF, and I've already bought a brand new one with no difference)

was quoted 360 + vat for the injector it's mounted in.

The EDC light will not light for a faulty needle movement sensor apparently.

 

[malcolm E53 AMG]

It might be a holed intercooler. What you describe, ie. the loss of power when the engine warms up would point to this. There are posts on this forum regarding intercooler problems might be worth doing a search.

 

[robbi-wan]

I have had a holed intercooler lasst year, and the giveaway was v.loud hissing/smoke etc. This appears to be different

Yeti- where would i find the needle sensor? What does it do and can it be tested?

rob

 

[robbi-wan]

Update:
Went shopping yesterday - symptoms as above: no change.

Just took it out and gave it a good thrashing from cold and all systems are go!
It did exactly what it says on the tin, i'll see what happens tomorrow......
Now i am a fairly rational person (used to be anyway) but this is getting on my fruit......
Any Ideas??
rob