Ozzy_B

iTrader: (2)

MY99 STi 5, only recently the revs every now and then drop below idle, requiring a quick blip of the throttle to bring it back to normal, it hasn't started stalling yet though when pulling up at junctions. When on WOT the lambdalink lights up to the top, or second to top green led, and also the knocklink, which a few weeks ago never used to light up at all, now lights the two bottom green leds, again only on WOT.

The maf is approx 1yr/5000 miles old since last changed, running normal airbox with panel filter. Does it sound like the maf is starting to fail? Also planning on doing a 240 mile round trip to Japshow on sunday, obviously will be taking it steady but should I get this checked out before I go?

Also not had a CEL but I checked for error codes anyway, it did flash code 23-maf sensor, but it has done that before and when done ecu reset the code goes away for a few months but pops up every now and again, not like its there constantly and the car ran fine, perfect idle, no knocklinc activity etc

edit -just read that the lamda sensor can also affect this, but as the voltage can be seen going up and down on the lambdalink, would this eliminate it? Is it normal when crusing on motorway approx 70mph off boost that there is no or very little movement on the lambdalink, it just stays blank with the odd flicker of the botom red led, but when on boost the leds rise through orange and green? Just dont want to waste £100+ on the wrong sensor.

cheers

Ozzy_B

iTrader: (2)

just checked all the pipes etc in daylight, seems the samco hose that fastens to the airbox was slightly 'off' at one side as its such a tight ba$tard fit and the angle it attches to the airbox means one side is on alot more than the other (when i say off, i mean the very smallest of gaps, not even really visible), also the clip holding it on seems to have slightly moved. Re-tightened/moved the clip and everything seems fine, still get the odd bottom green led flash on the knocklink but the idle seems fine etc. Might have to invest in some better/stronger clips, ah well saved me wasting £70 !