Geddon

Someone please help me.....

Ok car is MY00 uk turbo PPP and full decat.

Just recently it has not been boosting to the full extent- feels like someone has put a banana up the exhaust!
Its fine off boost and when you get to 6k ish rpm but from 2-3k it feels restrictive like when on a hot day when the intercooler cant hack it and the boost is cut. It occasionally spurts full boost like when an engine is occasionally missing a cylinder or water in petrol- that sort of thing.

I thought it might be the turbo since there is a whistling noise that comes from the exhaust (started about 2 months ago) but I thought a turbo smoked when it was on the way out. If not what are the symptoms?

Will it help resetting the ecu at all?

I read with interest in another thread about theories of split TMIC- is this possible? How would i test this?

I dont have a boost gauge at the moment but was considering getting one so I can get a better picture- i take it this is sensible?

Basically I dont want to go and spend $$$$ on another turbo to find I still have the same problem.

Any ways/ideas that I can use to diagnose the problem are greatly appreciated...................

Thanks in advance.........

Pete

Geddon

Any advice pleeeeeeease

Markyboy uk

Don't spend any money yet

Tried cleaning out the boost solenoid with brake cleaner? - If your oil level is above the upper suggested limit on the dipstick it can lead to boost solenoid contamination.

ECU Reset might be worth a try too (certainly before spending out on a replacement turbo anyway! )

Plenty of posts on here detailing how to perform both of the above.

Also check if your year/model had the dodgy MAF sensor (I cant remember which year(s) had) - If so, you may want to think about replacing your MAF sensor.

Geddon

Right just been out in it with a temporary boost gauge and am only getting 7psi throughout. I'm led to believe this should be 14- 17 psi?
Is 7psi the 'get you home mode'?
I have read about the MAF sensors and I thought they hunted at idle which mine is not doing. Although it is hunting through the rev range. I did have a green cotton air filter fitted at service a couple of months ago- could this have screwed the maf? Are these filters ok to use?

Am resetting the ecu at the moment to see if any change.....

Any more ideas?

Geddon

Well the ecu reset did nothing....

Markyboy uk

7psi is definately not correct.

It has been known for oily filters to sometimes contaminate the maf sensor.
If your problem has appeared since fitting the filter then that may well be the cause.
Here is a link showing how you can clean the MAF sensor (The link is for a Toyota MR2 MAF but the principle for cleaning the Scooby MAF is exactly the same)

http://spydermagazine.com/2002/March.../maf_clean.htm

Search on here (Scoobynet) how to check for a faulty MAF - I think if you disconnect the MAF while the engine is running this can help you determine whether your MAF is good or not (Can't remember though whether engine should stall or not after disconnecting- sorry).

Definately worth squirting some brake cleaner into the boost solenoid too.

vulnax999

iTrader: (7)

Carb or brake CLEANING fluid, not brake fluid!

Dave uk blue mica

i had a similar problem and mine ended up being the MAF gone

jpor

iTrader: (1)

Ummmm... Same sort of thing happened to me when I owned a MY00 and decided on upgrading the Air Box to a Blitz SUS air filter. What you have to under stand is that the air box is covered and helps stop the Hot air from getting in. In the end I noticed a very slight hunting at idle after having the SUS on for a month. And the lack of boost. Took it in to the local Subaru dealers for a diag. In the end I had the original air box put back on and a new MAF sensor. Luckily on the MY00 you can just get the new sensor bit and not the whole thing replaced for around £60 + V.A.T. After that the car boosted normally again.

Geddon

well thanks for all the advice)
Maf has been replaced and all is now fine with 14- 15 psi boost
Feels faster than before too!
I thought they just went - not over time. You dont tend to notice the degradation until a certain point but the step change afterwards was nice
Interesting that mine was not hunting at idle?!
Just really glad that with the advice of Scoobynet I didnt have to go to the dodgy boys in Botley!

jpor

iTrader: (1)

The hunting on idle was very slight and didn't always do it. Only noticed when stood at a set of traffic lights the rev needle move from 800rpm to around 7500 rpm now and again. So it was just showing signs of failure. I beleive a dodgy MAF can help cause engine failure if not caught early. Glad you got it sorted