Boost Issues

[928stu]

Hi guys.

I've got a bit of an issue with my boost.

I have a '99 S2 Stagea with 61000kms on it - and stock apart from a turbo timer.

It appears that I get 7lb of boost instead of the stock 5lb right from about 2500rpm - no complaints there, but after about 5 mins of driving it won't go over 5lb boost and is dropping back to 4lb boost at 5000rpm and feels 'lame' to drive and slow to build boost.

Now the funny thing, if I pull over and turn off engine and restart I get 7lbs boost again and is 'snappy' to drive for about 5 mins.

I've tested this quite a few times - the ignition must be turned off and not just letting the motor idle down and I get back the 7lb boost again.

First I thought it may be the cheap(looking) boost gauge so I rigged up another but they both read the same.

So I've been told(by local mechanics) it's

1) turbo is stuffed

2) fuel pump on it's way out

3) ECU playing up

Any ideas would be appricated

[QWK32]

i wouldn't have said any of those things. i'd be looking at the factory boost solinoid. it may be on it way out and playing up. or it already has the 'high' boost mod done on it, where you ground out one of the wires, and the grounded wire hasn't got a good ground connection.

[928stu]

I've had a look at the boost solinoid and all appears to be stock, no extra wire/s and all hoses look to be in stock position but I'll disconnect it and test it a bit later.

But why do I loose boost at higher rpms - drops down to 4lbs?

Thanks

[SHIZNT]

If you know someone with a bleed valve style boost controller or want to buy one for $25, plumb it up (only takes 5 mins) and see if it holds boost.

[_Ryan_]

first of all, get a consult unit plugged in and find out what is going on,

second do the 'free boost mod' so that you are bypassing the factory solenoid.