I've recently been losing power randomly on my 05 fabia vrs I checked for error codes and got p0299 (underboost)

I figured it must be a boost leak so checked all the pipework and they're all fine

then somebody recommended to clean egr so I did that ( no difference)

the code comes and upon clearing car returns to its former glory for a short while

before popping the error code again and losing power

 

I'm losing my mind researching this for days reading every single thread on every single forum and I've ran out of  ideas car will lose power and  struggle to get past 60mph unless downhill and dont seem to go much above 2k rpm when the power cut happens

 

I'm hoping that somebody here can help me I'm desperate to get this fixed as I have to use my car alot for work 

 

thanks in advance

Edited 4 September, 201510 yr by Kinglathwood

Strange no one has suggested it.

The vanes in your turbo are sticking, so the vnt needs cleaning.

Search Mr muscle turbo fix or something.

If your handy with a spanner remove the turbo and clean it properly on the bench, awkward job if it's a standard KKK turbo though.

It will be your problem though.

Check the intercooler itself is sound. Check the vacuum pipes from the "vacuum block" to the turbo VNT mechanism.

 

Usually any problems with intercooler pipes are at the joints or the one off the bottom off the turbo can shred.

 

You could try the "Mr Muscle" turbo treatment. To help eliminate stuck turbo vanes.

You should be able to confirm if the turbo is sticking by physically moving the actuator and, only if it sticks, do you need to think about steps to clean out the exhaust side with mr muscle. Its sounds like its the problem though.

Strange no one has suggested it.

The vanes in your turbo are sticking, so the vnt needs cleaning.

Search Mr muscle turbo fix or something.

If your handy with a spanner remove the turbo and clean it properly on the bench, awkward job if it's a standard KKK turbo though.

It will be your problem though.

Thank you so much for your advice I'm going to attempt this over the next couple of days and report back

 

Check the intercooler itself is sound. Check the vacuum pipes from the "vacuum block" to the turbo VNT mechanism.

 

Usually any problems with intercooler pipes are at the joints or the one off the bottom off the turbo can shred.

 

You could try the "Mr Muscle" turbo treatment. To help eliminate stuck turbo vanes.

All pipes have been checked intercooler pipes/vacuum pipes even had front wheel and wheel arch out to check intercooler

everything seems fine 

thankyou for replying to my thread all advice is good advice atm

 

You should be able to confirm if the turbo is sticking by physically moving the actuator and, only if it sticks, do you need to think about steps to clean out the exhaust side with mr muscle. Its sounds like its the problem though.

Do I need to get under the car to do this? if so are ramps/jack/axel stands of any use or do i need it on a lift

 

Thankyou to everybody who replied been struggling with this for awhile and it's really stressing me out will report back with any progress (if any)

If you want to check for sticking vanes on the turbo - you should be able to physically grab the actuator rod and move it in/out. Its a while since I have done this but it is my recollection that you should be able to reach this on a cold engine at the back and top near windscreen and wiggle it to and fro.

 

Just one other thing, on my car there was a dual sensor (MAP ?) down towards the driver side front of the car inside the engine bay just before the intercooler (1.9 tdi) that monitors boost pressure and something else - perhaps temperature. I had the same symptoms as you but I think my code was for overboost. Anyway I was working my way changing parts as I went and when I started to change out this dual sensor I realised the wires were fractured just before the plug it connected to. In effect the wiring to the pressure monitoring device was broken so the engine kept trying maximum boost (using the VNT pushrod) until the engine management system decided there was a fault and moved into limp home mode - as yours is doing, though probably for a different reason. Anyway - fixing the wiring fixed my car.

Edited 5 September, 201510 yr by poiuytre111

If you want to check for sticking vanes on the turbo - you should be able to physically grab the actuator rod and move it in/out. Its a while since I have done this but it is my recollection that you should be able to reach this on a cold engine at the back and top near windscreen and wiggle it to and fro.

 

Just one other thing, on my car there was a dual sensor (MAP ?) down towards the driver side front of the car inside the engine bay just before the intercooler (1.9 tdi) that monitors boost pressure and something else - perhaps temperature. I had the same symptoms as you but I think my code was for overboost. Anyway I was working my way changing parts as I went and when I started to change out this dual sensor I realised the wires were fractured just before the plug it connected to. In effect the wiring to the pressure monitoring device was broken so the engine kept trying maximum boost (using the VNT pushrod) until the engine management system decided there was a fault and moved into limp home mode - as yours is doing, though probably for a different reason. Anyway - fixing the wiring fixed my car.

Thankyou so much for the advice unfortuntely I had it inspected and turns out my turbo is broken play in the shaft apparently 

thought it could be fixed been quoted £500 for new turbo fitting and labour and a service

Edited 6 September, 201510 yr by Kinglathwood