S2 Overboost Problem


Registered User
I have a 1993 S2 6 speed which is awesome but because of a hugely annoying intermittent problem I am at the end of my tether with it. Basically under hard acceleration the car is liable to lose all power for a split second. Once this has happened the first time it will happen again with the slightest boost. If I switch the car off and start up again it may be fine for another few weeks!!! It always seems to happen when I really dont want it to like overtaking a truck on an A road.

I have tried the following;

Changed the boost control valve
Changed the lamda probe
Changed the MAF meter
Had the MAF meter wiring block re-wired.
Tried sweet-talking the car

None of which have solved it. I have already spent lots on diagnostics and havent even come close. Any ideas would be very much appreciated.

I am in the UK



Registered User
I have the same problem on my '94 S2 (ABY engine code). However, it's only surfaced twice in 3 years, each time it was in the winter when the whether was pretty cold. Let me know if you manage to solve your problem.