Happens very infrequently by coincidence in the same place driving home. Giving it some "beans" going up a relatively steep hill I see 5 slow flashes of the CEL.
Happened last night. Checked with ECU Explorer when I got home but no fault codes showing. Everything running as it should be otherwise

 

Year model and are you running a simtek ecu..

 

"02" WRX Wagon. 2.1 Stroker. ECUTEK/SC36 Turbo. 330BHP. Full decat.

 

Knock! Knock! Knock!

Are the SimTek/ECUTEC not wired to show knock via the CEL??

 

Dont know about ecutek, but thats how the simtek is set up.

You say you were givin it beans, did you bounce the limiter, if you did it might be set up the same way as the simtek, for knock.

 

Thanks for reply. No I never bounce off the limiter. Happened again today this time after some "spirited" driving up to a max of 6K rpm. Then after driving normally at about 50 mph for a mile or 2 had multiple slow flashes of the CEL then it stayed on. Checked with ECU explorer - no faults showing. Reset ECU, CEL gone driving normally still possibly a bit smoother.

 

Think you need to speak with you mapper, and perhaps get it on the rollers mate.

 

Trip to Plymouth coming up then

 

Popped down to EngineTuner this morning to get Martyn to check the codes. Even before he plugged it in he said "Dump Valve !!". I had a forge recirc fitted when the engine was done. Stuck the OE back on now - problem solved

Apparently the issue seems peculiar to WRX's

 

This is the beauty of taking to someone that's a specialist in these cars for years, rather than speculating and getting freaked out/frustrated/upset (not saying you did, of course) .

Ergo, there's a very good chance said specialist will have seen the issure before - as has no doubt happened here - and recitifed it in a thrice for very little/no outlay. Cool.

 

Dead right. The frustration had set in plus getting freaked by what the hells gone wrong now !

Took 10 minutes tops to confirm his suspicion and change the DV

 

Short lived cure. 100 miles and the CEL was back on. Reset ECU checked plug gaps 100 miles CEL back on. After a process of elimination and head scratching turned out to be the NPS.

 

So NPS replaced.... NOW all sorted, yeah???

 

what is NPS?

 

Neutral position switch.

 

Text speak for nipples.

 

Stop it!

 

Yep. Running great now. Knew there was something amiss when it was mapped by Martyn at 345 BHP and only got 315BHP on a club RR day!

 

Boodiful - that's more like it!

 

Another one to add to the list Malc !

 

Glad it finally got sorted.

 

Thanks for all your help Martyn
Car really is nice to drive now. The 2.1 stroker pulls so well now, even from low down. Roll on Japfest and some track time

 

I have been having exactly the same problem. Happens at the same point on the same road, infrequently.

Did the same thing this morning and the light stayed on, permanently this time.

Going to try and get the fault code read this week, but I'm glad I have a rough idea what it is.

 

Sounds very similar. Is the car running rough now? Fault codes didn't show up on ECU Explorer but did with Delta Dash. Looked like a misfire code from memory.

What car have you got and is it mapped?

 

Mine's an MY03 WRX, EcuTek remap. I tried to get any fault codes read the first time the CEL flashed (about 18 months ago) but no historic fault codes were showing at all.

Since the light came on permanently, I've only used the car for about 18 miles, haven't been driving hard until I can get the fault checked so not sure if it's running noticeably rougher than usual.

 

Yep same as mine. Had odd issues after ECUTEK done but when the power was really cranked up the fault got worse and worse. My recommendation would be to change the switch. Reset the ECU and see what happens. Takes about 10 mins. Get the front of the car up on ramps. The switch is on the nearside of the 5 speed box. (The one nearest the back). and "Roberts your mothers brother." job done.

Quick delivery from here.

http://www.importcarparts.co.uk/part...ition%20switch

 

You need to make sure that the NPS is for the exact year/model.

NPS is VERY common problem on bug wrxs and stis (roughly half of the cars I see have a problem with them) but becoming increasingly common in blob eyes too.

On the wrxs they tend to just flash the CEL light but occasionally they stay on and show codes for misfires and also cam position sensors.

On the sti model they have a much worse effect as they can switch the cam advance off and make a sti performance very lack lustre or hesitant on top of the random CELs.

 

Duncan/anybody,

could the NPS cause low alternator voltage fault code and/or TGV butterfly codes?

thanks

 

Not in my experience

 

Update. Replaced NPS and problem solved.