cloudy

My MY98 turbo runs fine for 15 minutes - I can accelerate hard through the gears etc.
Once past this time - hard accelerating at 3200 rpm and above causes a sudden cut out like the engine is getting no fuel - backing off corrects the problem. Light acceleration doesn't produce this cutting out and I can get to higher revs without a problem.
Is this an ECU fault - or fuel pump ? Anyone suffered this before ?

cheers

WRX Youngster

iTrader: (1)

Could this be the boost blowing the spark out, what are your plug gaps like, are you running standard boost?

Luke

cloudy

yes - standard boost. Plug gaps within tolerance. The cut out is a total cut out - like a brick wall - then power comes back again.

cryptwalk

If the rev counter drops to 0 fo about 3 secs then back up it's overboost, i'm having the same problem at the moment.

MattRus

Sounds like ECU is detecting over boost and signaling a fuel cut.
Have you got a boost gauge fitted, if so what pressure is showing?
If not check wastegate plumbing as suggested. Could be that the ECU is receiving an incorrect MAP (pressure signal) and thinking it is overboost, this could be a faulty MAP sensor. Although I am not sure on the standard failure mode of this type of pressure sensor!

Incidentally, 'blowing the spark out' is possible but is not normally a total engine cut more of a misfire. Plug gap's seem best set at 0.6 - 0.7mm.

ktulu

Is that about 3000rpm in fifth only, about 80mph?

thats the highest boost level on a my98

Brynweb

Listen to Stuart Taylor.
Sounds like the restrictor hole could be a bit blocked.

cloudy

Thanks to all - pipes cleaned etc but only marginal improvement.
I'll try increasing the restrictor size next...

S3LDM

Dont know if this is any use to you but I experienced the
exact same problem when I put a blitz induction kit on my
MY98, have you modified your air fillter at all...because
I did not have problems straight away..

SteveB

iTrader: (1)

I used to get this problem in my old MY97. Try filling the solenoid with brake cleaner and connecting the two green plugs under the dash together to start a self check sequence. You'll hear the solenoid clicking. Blow through all pipes with the same brake cleaner and hey presto - problem solved for a further 6 to 9 months.

Cheers

Steve.

Moles Dad

Is it the 1st of April ?

Oh no its the 8th, blowing the sparks out???

Sounds like OVERBOOST

[Edited by Moles Dad - 4/8/2002 8:18:05 PM]

Stuart Taylor

Have you changed you fuel to Optimax recently? Does it only really occur when the weather is very cold?
I have a MY98 and recently started using Optimax. The car was really starting to fly after a few weeks but then I got Overboost which sounds exactly the same symptoms as yourself.
Firstly try cleaning out your boost solenoid and all the pipework with brake cleaner. And check all the pipes are OK. There were plenty of explanations on here on how to do it.
If the overboosting still persists then you may need to increase your restrictor size.
I was recomended to increase the restrictor size by .1mm which I did and I havnt had overboost since.
To increase the restrictor size you will need to buy a set of precision drill bits from Maplin. I found they only had ones which went up by .2mm. I bought these and took out my restrictor. I put the 1mm drill bit in the hole and it fitted but was a bit loose, I then tried the 1.2mm and it didnt fit. So I assumed the hole was about 1.1mm and drilled it out to 1.2mm. Its all been fine ever since.

Stuart

[Edited by Stuart Taylor - 4/9/2002 2:04:39 PM]