Right, I replaced my NPS yesterday. It may have no bearing on the fault code but letting you know just in case. I have had the above fault code (P0172) when sat idling, cleared it with the PSI3 and it came back in the same circumstances. I understand it is running rich, or appearing to be.

Any tips anyone on how to diagnose positively? Can I clean my MAF? Its a Bug WRX, mapped with a few upgrades.

 

You are running DV?

If yes which one?

Can be just something like ECU throwing false CEL(as bugeye ECU are known with this) or can be grounds(my friend has similar problem and turned to be faulty ground on headlights)


Jura

 

I am using the std recirc valve. Hopefully it's just a false CEL. I'll keep an eye.… thanks Jura

 

AFR reading 12.0:1 on tickover on my PSI3, anything to worry about?

 

This will explain everything about the AFR

http://www.subaru-impreza.org/forum/...ned-afr-s.html


Jura

 

Interesting, if I read that right I'm running a little rich but not drastically. What can cause the change, and can I spray clean the MAF with IPA or a similar fluid to clean it up?

 

have you checked the o2 sensor?

 

Is there an easy check? Is that the one 'behind' the downpipe?

 

Not really an easy check as far as i know, just if you know anyone who can get there hands on a known good one and just swap to see if it makes any difference, Think its the one in the headers, My mate had an issue with a CEL turned out it was the sensor, Just a thought.

 

I spoke to Duncan, who suggests a vacuum pipe into the inlet manifold may be split. Could anyone put up a quick pic of the hoses I need to be checking, Bug WRX of course!

 

Hi there here all manuals for Impreza etc.

http://www.mediafire.com/?sharekey=5...21d66e282a0ee8

Or this can help too

http://www.turboboostleaktesters.com...WRX-STI/Detail

Jura

 

Cheers Jura, I'll have a look tonight.