DaveMcC

The main dealer has had 2 attempts at fixing this with no luck, so can anyone on hear shed any light?

The problem is only apparent on changing from 2nd to 3rd. When 3rd is engaged and the throttle floored there is a momentary engine kill (I assume it's a fuel cut - it feels like the "brick wall effect" others have talked about). Following this it accelerates fine. It only happens if you have more than about 6,000 revs in 2nd before changing - less than this and no problem.

The problem can also be avoided by pressing the accelerator more slowly after the gear change.

The dealer first cleaned the boost control solenoid. Attempt No. 2 involved replacing the solenoid, but still no joy. They have now logged a query with IM's technical department as they don't know what to try next.

Car is a UK MY00, mechanically standard. If all else fails I'm booked on the sussex RR day on 10 Nov so will see if they can have a quick look then.

(ps I know it's not just my driving cause I drove a MY00 with PPP and it didn't do this!)

TIA

Dave

DavidLewis

Dave,

I had the exact same problem after my restrictor was made smaller during a PE RR tune. Fixed by re-drilling the hole slightly larger.

Maybe the restrictor has become a little blocked?

Hanslow

Keep us posted My MY00 does this too. I had just put it down to my driving

I find I have to feed the accelerator back in slowly rather than planting it straight back down. I thought it was another they all do that sir

Be interested to know the solution....then I can pop down the dealers


[Edited by Hanslow - 10/31/2001 12:52:16 PM]

NM

Hi All

Doesnt sound like overboost to me as this tends to happen between 3k5 and 4k5 revs in every gear. Cant help with a solution but I was plagued with Overboost for a month when I first purchased a MY98 earlier on this year. In the end it was down to the None Subaru garage that was selling it, they had done a quick oil change service and had replaced it with too much oil which contaminated the restrictor and pipework. Reducing the oil level and cleaning the pipes worked.

Your problems sound like something to do with the ECU rather than Overboost.

Hope you all sort out your problem with your cars.

Cheers

Neal

FamousCoops

I had the same problem i had the boost pressure checked etc ,then I filled it up with luverly OPTIMAX and drove it like a stole it after half an hour it didnt miss a beat no holding back not a hint of lag etc since then its optimax every time .its luverly.

johnmjohnny

I have had the same problem to but it hapened after fitting a bleed valve i have removed it and it is still overboosting i cleaned all the pipes changed the solenoid valve and the two valves that sit next to it,i was told it was the ecu and have tried another ecu and it is still doing it i put a boost gauge on it and it was sitting at 13psi and peaking at about 15psi then the fuel would cut the car is a 93 wrx i have just bought a hks fcd hoping this will stop this problem in the meantime till i get it fixed i have also made the hole in the restrictor in the wastegate piping a litle bigger but still no joy i have a feeling it could be something silly like a tiny hole in one of the pipes but i cant see any thing any one any ideas.

AJbaseBloke

try the earthing trick - cured my car of the big spikes.

Hope this helps.

NM

John

Check your oil level on a very ***'FLAT'*** surface. Mine was at the max limit which was causing my overboosting. What happens, the oil fumes contaminate and cover the restrictor reducing the hole size and thus the solinoid sees a higher boost. Remove some of the oil from the engine so that the stick indicates just over the lower mark, then clean out all your pipes and solinoid with brake cleaner spray. It may require a few goes, warning I had a brief starting problem after cleaning the pipes but on the 3rd key turn bobs your uncle.

Cheers

Neal MY98

LEN CARLYON

Hi Dave
I think I might be able to help you,
visit www.subaru4you.co.uk and give me a ring, you might have to leave a message at home/office, I'll get back to you.

Len
PS when accelerating, excessive boost pressure is created, the ECU senses it via the waste gate control valve, thus the ECU fuel cuts causing momentary loss of fuel, but at full boost it is like hitting a wall. Then as soon as it went its back to reduced boost whilst its building up again.