Cleaning The Cold Start Valve

[simpletool]

I used Nulon Upper Engine cleaner a couple of week ago (similar to Seafoam, Subaru Upper Engine Cleaner). It all seemed to go well. I sprayed it into the plenum via a few different vacuum lines and sprayed a fair bit into the fat tube going into the AAC/cold start valve.

The problem is that my cold start is now bad. Is it possible the cleaner has damaged anything in the cold start valve?

When I start the car from cold it blips up then stalls. I have to repeat 2 or 3 times and the idle will be rough and low (~400rpm) then a few seconds later the revs quickly rise to 1400rpm and it is all good. The AAC valve seems fine and controls the idle well after the initial stumbles when cold.

I thought I might have gunked the cold start valve since it sits at the bottom of the tube. So I have tried to clean a 2nd time with the Nulon stuff. It certainly gets it started but when it cools down again it hasn't helped.

So perhaps some caution should be used with the upper engine cleaner when squirting it into the AAC tube. If I sort the cold start out I'll post up the issue.

Edited August 21, 2011 by simpletool

[gotRICE?]

Possible you might need to adjust the idle perhaps?

Now with all the gunk gone it might be letting too much air through on cold startup compared to what it was before.

[Room42]

Possible you might need to adjust the idle perhaps?

Now with all the gunk gone it might be letting too much air through on cold startup compared to what it was before.

I was thinking along the same lines. Mine sticks a bit at 1200 and wont idle lower than 900 even when I set it to 500. Should go give it a clean I spose

[simpletool]

Yeah I was thinking that was possible - no time yet to do a proper idle adjust.