Hi have just picked up my '99 T Reg Impreza classic. It drove like a dream on the way back - but under hard acceleration the red check engine light flickered now and again.

The car ran perfectly smoothly and felt fine to me. I've read that codes can be pulled on Imprezas quite easily. Is this the best way for me to find out?

Also, the car has a performance exhaust and downpipe, could the heavy emissions under hard acceleration be the cause?

Many thanks

 

maybe knock sensor.......

get her plugged in see wat comes up as a diagnostic code

 

is the knock sensor serious? Also, I put 95 Ron unleaded in the car - I guess the knock sensor would notice the 95 Ron, if the previous owner put Super in the car.

Is there a guide on pulling codes, couldn't find it?

thanks

 

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rapid flashing CEL IS KNOCK!!!
never run on 95...you need Vpower or similar

 

The standard CEL doesn't flash if it detects knock since he has a UK car then he can run 95ron but would be better off with 97+ron

 

Hi thanks for the help. I will run it on super for from now on just in case. Do you think it could be related to knock then, or is it ok as it's a UK car not an import

 

Just get the ecu read to see if there any codes stored then proceed from there.
To get the best out the car use 97 or above (except BP ultimate which doesn't agree with imprezas).

 

Tried plugging in the black plugs under the steering column a few times. No codes came up when I turned on the ignition? I also tried the reset procedure by plugging in the green connectors as well and no codes there either.

Think it needs a trip to a Subaru garage

 

Yes i would, best get it plugged in. Never ignore the CEL, it could prove costly.

 

I reset the car the other day by unplugging the battery for an hour or so. Amazingly I haven't seen the CEL flicker even once anymore. I have tried to make it flicker by accelerating over 4000rpm (it usually appeared around 4000rpm before), yet the light refuses to come on.

It has had a few fill ups of 97 Ron since though. Maybe it was a knock sensor after all, due to me putting 95 Ron in the car the first time I drove it?