uzzy-swr

hi there. i recently just bought a 94 subaru impreza wrx. its my first turbo and i dont know much about it. im having a problem while driving. when i drive the car fast usualy in second gear or upwards the power cuts off around about 5 revs and then kicks in again and then this will happen again etc. what could be the cause of this problem. any help will be appreciated. cheers. uzzy

joey_turbo

iTrader: (26)

Possibly fuel cut where the boost is runing too high. Do you have a boost gauge?

uzzy-swr

yes i do. it shows am running on 1.1bar boost. what do you think may be the problem mate? how could i chek ecu errors becuase sometimes the ecu light comes on aswel.

joey_turbo

iTrader: (26)

1.1 would be on the limit of the fuel cut. If for whatever reason, mostly the cold air, that you boost over that, it will be fuel cut time. Does it have a boost controller?

How to read the ECU codes:

Scoobypedia | Trusted knowledge for everything Subaru | Knowledge / Reading ECU Fault Codes

uzzy-swr

no it doesnt have any gadgets like that. its just got a straight through jasma system. i've been told its got a sti td05 turbo. the boost gauge shows 1.1bar when you floor it. what fuel cut problem could it be mate. am sorry this is all new to me lol. i've got alot of learning to do.

joey_turbo

iTrader: (26)

IF it is fuel cut that is. Its there to protect your engine running too much boost. Get a boost controller and lower the boost. 1.1 Is the limit, so if it is fuel cut, it must be going over that.

uzzy-swr

the car feels like its running around 290 to 300bhp. do you think it must be a td04 turbo running high boost. it also has a blitz front mounted intercooler. what would be the best modification t get a little increase in power. cheers

joey_turbo

iTrader: (26)

Mate, I've no idea how you would be able to feel the BHP.
Best thing to do is have a proper look over it. If it has had the turbo upgraded, the very least I'd expect to see is a boost controller. Same goes for the FMIC. The ECu would have to be remapped aswell, otherwise it would be running very bad.

myblackwrx

iTrader: (1)

your standard turbo is a td05 and i would be surprised if it's a td04 (they seem to run out of puff at about 280 allegedly.
Before increasing the power i would suggest you sort out the boost problem a quick run on a rolling road may give you some info on the problem.
The bottom hose coming ut of the boost solenoid should have a brass restrictor in it without it this may be causing the overboost.

uzzy-swr

i'l take a look in the morn. is there any place near manchester if not in manchester that could take a look and put it on a dyno. cheers pal

adam6900

iTrader: (4)

I had a Dodgey coil pack on my one that caused a miss every once in a while, Every time it missed that trigered the ECU in to Safe mode and cut the power for about 3 seconds, so its not just overboost that does it

Clarkee

Check for fault codes as mentioned before, i had a problem like that and it turned out to be the knock sensor.

Baker

Ive just had my MAF sensor replaced as it died on me. Ive still got the same problem as you basically but it only happens in 4th gear when on full boost high up in the rev.

I like you will be taking it to be checked out and hopefully it will be something simple, cant stand these problems when you dont actually know what it wrong but potentially could spend a fortune on trying to put it right!

X865

I have the same problem in my 03 wrx, but how do u look at a boost gauge when pulling 5k revs in 3rd

joey_turbo

iTrader: (26)

The same way you look at it when the car is stationary

A clear road helps.

dynamix

iTrader: (3)

Get someone else to sit in the car with you and watch the guage.

or get it on a rolling road where you can see what is exactly happening.

I very much doubt it is running 290 bhp from changing an exhaust but the rolling road will tell you where it is and whether it is safe.

X865

Dont have a boost gauge but do have the (intermittent) problem looks like will need rolling road. Got to 6500rpm in 2nd and no sign of problem

dynamix

iTrader: (3)

I'd be very surprised if you hit overboost in 2nd.

X865

so is this a problem to be fixed or is the engine protecting itself?

spinny25

[i had same prob it was stock boost controller