Oh The Subaru Wooos

[imprezapete]

Hey folks

Nice to see this place is still about, been a while since I've read or wrote on this place.

Anyway Im looking for some info or advice please

I had a warning light come on my Impreza 2002 WRX with a few light mods, nothing serious. Mainly Turbo back exhaust changes.

Anyway I took it down to Chris Alan at East Linton Services who plugged it in to his handheld to reveal it was the Knock sensor playing up. Anyway that was last week and we discussed it and choose to simply reset it and see how it goes.

But today this morning it came back on and shortly after I think the car when in to Limp mode as the power was mostly gone in the higher RPMs and I didnt want to push it. It was a little unsmooth as well applying what power was left as well.

Anyway my question is about weather this sensor going would cause this effect, because if thats a no I worried I'm in for a large or expensive issue.

Regards

Pete one worried owner

[thefastone]

Well at least the car has gone into Limp mode, it should at least protect your engine a bit, even if its horrid to drive like that... Dont know how much the sensors are to replace, how how to test them, but I'm sure that there should be a way to find out...

[thewelsho]

Well at least the car has gone into Limp mode, it should at least protect your engine a bit, even if its horrid to drive like that... Dont know how much the sensors are to replace, how how to test them, but I'm sure that there should be a way to find out...

I can't imagine replacing a knock-sensor would be a great deal of money, but I think it might be a pain to get to, so there might be a couple of hours in labour to replace it. If your KS isn't working correctly then yes, I would imagine that you would experience those symptoms. The senor being faulty, will retard the timing and store the values. The next time knock is detected, it retards the timing from the stored values, therefore, the symptoms get progressivley worse. I had a simialir issue, where the timing was retarded on account of the KS picking up "something". There was no CEL as there was no issues with any component; my issue was a cracked ringland which the KS picked up on.

Your case seems to be much more straight forward in that your KS is faulty. Try swapping it out for a known working version.

Edited November 27, 2009 by TheWelsho