[KitNYC]

Howdy from Texas, y'all....

My '04 RS seems to have developed a bit of an issue since I got down here. I don't know if it's the hot weather, the fact that I just rolled over 35k on most of the bike, or the fact that the engine is at 18k, but my idle keeps dropping to 800, sometimes 500, and sometimes all the way to stalled. I'm not seeing any issues with it when I'm actually riding; it seems to happen only at idle, possibly only in neutral

Anything in particular I should look at for this? I don't actually have much of a place to work right now, but I do have tools and a TuneBoy.

Thanks,
-Kit

 

[frider]

Co setting/TB balance, maybe the IACV valve sticking/gummed up....Tuneboy should give you a fault code...if it's the above..

is it missing at all on one cylinder??, might just be a simple 'plug' issue........

 

[KitNYC]

You know, there might just be an intermittent miss....

No check engine light, so I assume no fault codes either.

Thanks,
-Kit

 

[Calliway]

Probably wont be the IAC as that really only comes into play when you let go of the throttle.

The IAC is a little motor that keeps the butterfly's open a smidge when your hand isnt.

TB Balance (if they are way out) or your Throttle position sensor might need to be adjusted. You can adjust it small amount. This would also cause a small misfire much like a bad plug.

 

[inewham]

Swapping the coils did the trick for me.

Mine had a less than stable idle since i got it about a year ago - worked through lots of things trying to sort out its various issues; cleared water out of tank, big service, replaced all IACV hoses, IACV ceaned, TPS replaced, ECU replaced etc. and while everything improved things noticeably the tickover remained uneven.

Sometimes it would run just fine, other days it would hunt and vary in speed. A new set of plugs would sort everything out for a couple of weeks and then it went back to the usual instability. Never had a MIL light, everything fine over 3K. The coils looked fine, no tracking or cracks, no water ingress on LHS.

I got the hunch that coil might be on the edge and would fire a fresh plug but struggled as the plug saw a bit of use so swapped them for a set of 2nd hand coils and the bike runs sweet now.