I have a 93 Import Classic Impreza. When I was driving along uphill as the car came onto full boost in 3rd it sounded like it backfired and suddenly lost power. It now sounds very rough, as if it is running on 3 cylinders and won't rev with beyond 2000 or on anything other than very slight throttle. Luckily I was only a mile or 2 from home so managed to nurse it home at about 25-30mph much to the love of my fellow road users. The CEL also came on close to home.

I did an ECU check and got the o2 sensor code, the car has a decat and the o2 sensors are bunged up. They were like this when I got the car in January. It is also the first time the CEL has came on. I personally thought that the coil pack or a spark plug had gone but seeing as there is no misfire code I am a bit perplexed. There doesn't appear to be any smoke either.

I moved the car into the gararge from the drive and it was reluctant to start and still sounds very rough. I've disconnected the battery for an ECU reset.

If anybody has any suggestions it would be appreciated.

 

Think we need a sticky for these symptoms!

1st thing todo is check the big hoses from the airbox/filter all the way to the inlet manifold. Hopefully you've blown one off or split one maybe

 

I've checked all the hoses and they appear fine, as do the boost hoses

Cheers for the repply

 

o2 sensor is in your manifold not downpipe.

 

So do you reckon that is the culprit?

 

if the code has been brought up as o2 sensor tbh more than likely.
Reconnect the battery and see if the car will start properly

 

Turned out one of the jubilee clips had snapped off the boost hoses popping free. Will be replacing the o2 sensor in due course if the light comes on again. Cheers for the reply