SNH

just got the s back on the road after 2 years and am having a few teething problems - got a CEL P1519 IACV malfunction but after reading about others with same code mine doesnt seem to be doing the same thing - idle is steady (not dropping as if its gonna stall ) however it is doing the opposite revving up and down although never dropping below 1000 revs when idling - it seems ok when cold and apears to do it once the car has been warmed up and driven in the VTEC - once it starts doing this pulsating idling it is almost impossible to drive with low revs as it kangaroos - although as long as the power is slightly on it drives as normal even when the vtec is being used - there has never been any misfire . have cleaned everything - had the IAC off and cleaned, throttle body cleaned also , air filter etc ok also reset ecm and done relearn for idle - once reset the CEL goes off until its warmed up again - just dont know what to do next help needed please.

loftust

Have you tried a MAP whack?

Bandit_287

Seems to be a lot of idle issues around at the moment,my car included. Try disconnecting the THROTTLE POSITION SENSOR check faq for pics and location,give it a spary with electrical cleaner. You will get a CEL when you disconnect it but an ECU reset or battery disconnect will turn it off.

I had a similar issue to you, but it wouldnt idle and stalled not the erratic up/down idle like your having. I cleaned the IACV put it back on and it was still doing it but after a 25 mile drive the next day it seems to have sorted itself out.

If you are having kangerooing issues when pulling away i would take a look at yout MAP sensor on top of the throttle body, maybe remove it agive it a clean up and see if that works.

Bandit_287

P.S. Years ago i was having very similar issues to you on my Mk2 Golf GTi, the idle was up/down all over the place and it was the TPS that needed to be replaced so it's worth checking that out...

SNH

thanks for your help - will check out all of your recommendations and see how we go- just wanna get out in her now !!!!!!!!!!!!

MB

Tried the FAQ?

Bandit, you have an unusual obsession with the TPS! It's very rare they are faulty.