Hi,

Hoping someone can help! Ive just had my Import '99 STI 5 in for an MOT and it failed on a couple of major things. The first is that the ABS light is not coming on, on ignition and secondly my CO level was 8.72% well over the limit which is stated at 0.50. Any ideas what this could be? The garage couldnt look at it anymore as they said it needs to be plugged into a computer to see whats up. The other problem which could be related is that when the car is idleing the revs jump up and down between 0-1000 contantly, this has been going on for a while also which makes the car sound pretty rough. Any ideas would be appreciated.

Cheers

DAL

 

I had dodgy idle ages ago and it turned out to be a faulty O2 sensor. Also caused over-fuelling, so I'd suspect your O2 sensor is needing replaced given your symptoms.

Stefan

 

same here, idle all over the place. put a universal lambda in 2day and its running great again.all the best.mark

 

Nice one, hopefully that will be the case. Cheers.

DAL

 

Because your car is an import the limit should be a lot higher than that?

 

I'm not sure, someone else said that but even so 8% seems way to high still plus when the engines running it smells so strong. Any ideas how much the sensor would cost?

 

That is very high and indeed the most likely thing would be the 02 sensor... Unless its been decatted without your knowledge But still wouldn't be that high.

I would ring www.brdevelopments.co.uk as they do them at a good price. Basically, you can get an OE one, which is quite expensive, or you can go for the cheaper one from Halfords, which is a universal one for about £30 (not my cup of tea) but you will have to adapt the connector on it. There are many on here who have successfully fitted them.

Power Engineering or Xtreme Scoobies are also a good source.

Just to add, I think a duff MAF can do this, from memory. Thats an equally likely culprit on your year of car.

MB

 

Halfords do a universal O2 lambda sensor i think the code is L300 ...i paid £25 for mine, fitted it about 4 months ago ...works a treat.

Frank

 

OE one is approx. £120

Stefan

 

..well mine sti 1 was running 12% emissions -went like stink . But idle etc lovely -changed o2 sensor br dev (above) 120- actually for car or 300 i was told thro dealer . Thro mot with 0% !!!? .From what ive read on here ruf idle could be maf probs

 

The cars booked into a Subaru dealer this week as it needs a 60k service also but I'm hoping they will find out the cause of that idling problem its getting worse. Strange thing was you used to be able to turn the Air con on and it would stop it dead.

 

The car would stop? That sounds like some current drain/ earth fault / electrical issue?

MB

 

I would say a problem with MAF (my idle was shot to bits until i changed it - car would stall or nearly stall when dipping the clutch) - replaced MAF and all was fine. I belive that a faulty MAF can cause BIG bangs (dont mean to scare you), as it can underread the air going to the engine and run VERY lean - I think lambda can do this too but not to so much a degree.

I would drive the car fairly slowly (i.e. not using full boost) until you have got to the centre of the problem!

Dont let Subaru sell you the full MAF assembly, you only want the uprated MAF sensor (slightly stronger) - if it is the MAF!

 

The O2 wont cause a blow up in the way the MAF will, and you are right, a duff one will run lean.

Im not sure whether the STi5 MAF is the same as a UK MY 99/00. Certainly you can just buy the elemnt, (cheaper) but the part no may be different? Give Xtreme Scoobies a ring.

MB

 

part number is the same (for a STi 5 Type R anyways), i got one 2 weeks ago, I will try to dig out the part number for you! I believe it is an uprated part (i.e. slightly stronger - but still weaker than a weak thing thats been starved for 40 days - if only search was up and running for non plus members!)

 

MAF sensor = 22794AA010

 

Thanks for all the help will see what Subaru say Thursday and then pass on your comments! Cheers