ML270 (163) Down on Turbo Power; Help Pls

[richbrowne]

Hi,

The best way I can describe the fault that exists is as follows:
When you slow down and then floor the throttle, there used to be approx. a seconds delay and then the car would surge forward as the turbo came to life. If you do this now, there is still a surge but it is no way as urgent as it used to be; very deflated as though someone has suddenly either fitted a smaller turbo or turned the boost down.

Yesterday I removed the top engine covers, the air filter housing and associated pipework and the undertrays to get a good look at the wastegate vacuum and intercooler pipework and I could not see any split pipes or leaks anywhere.

I noticed that on the left hand side, the small filter hanging below the vacuum rectangular unit (sorry don't know its name) connected to the vacuum reservoir unit (round plastic item) was very dirty so I pulled this off and tried the car without it but it made no difference.

I can hear the turbo spinning up and a sort of whoosh sound on the drop of revs that I assume is the waste gate opening?

Does anyone have any ideas please? Could it be that the intercooler is dirty? Could the turbo itself be faulty or maybe the wastegate vacuum circuit is faulty?

Thanks in advance for any help you can provide.


Rich.

 

[Cosworth]

Check your throttle pedal, there should be no play in the pedal.

My ML had a spring broken inside the throttle cable and I lost at least 20% power in pick up.

 

[Mark A]

Could be the MAF - very common. When it went on the wife's ML it felt like it wouldn't pull the skin off a custard. +/- £65 later and all was well. Just make sure you go for an original not an e-bay copy.

Mark

 

[richbrowne]

Could be the MAF - very common. When it went on the wife's ML it felt like it wouldn't pull the skin off a custard. +/- £65 later and all was well. Just make sure you go for an original not an e-bay copy.

Mark

Hi Mark. The car did have an issue with the MAF that was sending it into 'limp' mode. However, this has been corrected during a recent service. The power reduction problem existed prior to the MAF issue.

 

[Parrot of Doom]

When was the fuel filter last changed?

Also, if you can get the codes read to see if anything has been flagged.

 

[Cole@MBS]

Just changed a in-let manifold due to inlet port shut of flaps broken up, that was having the same problems!

 

[richbrowne]

Just changed a in-let manifold due to inlet port shut of flaps broken up, that was having the same problems!

Thanks. I had heard that this could be a possible cause. What is the easiest way to diagnose this please?

 

[richbrowne]

When was the fuel filter last changed?

Also, if you can get the codes read to see if anything has been flagged.

It was serviced last week and had the fuel filter changed then.

 

[richbrowne]

Anymore ideas please?

 

[kebo57]

Thanks. I had heard that this could be a possible cause. What is the easiest way to diagnose this please?

Hi here are some pics
first pic is the inlet port shut of flap
second pic is the in-let manifold up side down with the operating motor you can see the rail move farwards & backwards through the gaps in the in-let manifold when you rev the engine
also feel for it under the in-let manifold from the back it is possible to check all the linkages but it will be very difficult if you haven't done this before
also see this from under the motor

Kevin

 

[richbrowne]

Hi here are some pics
first pic is the inlet port shut of flap
second pic is the in-let manifold up side down with the operating motor you can see the rail move farwards & backwards through the gaps in the in-let manifold when you rev the engine
also feel for it under the in-let manifold from the back it is possible to check all the linkages but it will be very difficult if you haven't done this before
also see this from under the motor

Kevin

Thanks Kevin.
So I guess I take the top covers off the motor and feel the linkages underneath to make sure they are all connected properly and to ensure they move when the car is revved?

Presumably they should close when the throttle is closed?

 

[kebo57]

Thanks Kevin.
So I guess I take the top covers off the motor and feel the linkages underneath to make sure they are all connected properly and to ensure they move when the car is revved?

Presumably they should close when the throttle is closed?

Hi yes "top covers off the motor" then if you look between the gaps in the in-let manifold near to the engine you can see the rail move which in turn open all five flaps at once, (you can't see the flaps open from above) only the operating rail move back & farwards.

Kevin

 

[johnyb]

Hi Kevin

I am having a problem with my intake port shutt off. Today I found that the arm/rod connecting the servo motor to the long rail wich the flaps are attached to is missing.
What would you suggest to do to see if any of the flaps are broken or stuck? Should I be able to move this rail with my hand closing and opening the flaps? I tried moving in back and forward but couldn't get any movement in them?

I can still drive the car but just very little power. Is there anyway to overide the system so to speak and just leave the flaps open?

Look forward to your reply,

Regards,

Johny

 

[kebo57]

Hi Kevin

I am having a problem with my intake port shutt off. Today I found that the arm/rod connecting the servo motor to the long rail wich the flaps are attached to is missing.
What would you suggest to do to see if any of the flaps are broken or stuck? Should I be able to move this rail with my hand closing and opening the flaps? I tried moving in back and forward but couldn't get any movement in them?

I can still drive the car but just very little power. Is there anyway to overide the system so to speak and just leave the flaps open?

Look forward to your reply,

Regards,

Johny

Hi Jonny I've just replied to you email but didn't read this first

What would you suggest to do to see if any of the flaps are broken
The flaps should operate by hand if you can get you hand to them (engine off) as the main link is missing, sound like yours are jammed,
also the servo motor should be operating you could feel for this as well when you rev the engine.

Kevin