Funny idle
 

Well after this last weekend my cars been idleing funny.

First ill tell you what all i did.

I fixed my intercooler, mounted it higher, got new rubber connecters to get me the extra room i needed.

I installed my bipes, and its retarding timing like it should, everything great there.

And i turned my wastegate another turn, so im pushing 6psi instead of being under 5.

Now when i installed the bipes i DID unplug the battery 100%.

The idle yesterday right after everything was done and i started it up would go to about 1600 stay there for a good 10 seconds, drop to 800, up to 1100, down to 800 repeatedly.

I thought this was a vac leak, so i checked all of my lines, couldnt find a single vac leak, and i sprayed every connector and all the piping with carb cleaner to find the leaks, and no luck there.

Now after putting more miles on it the idle is alot better seemingly, but still fluxuating. When i stop it will no longer stay at 1600 and will immediately drop down to 800 and up to 900 and down to 800 just slightly annoying.

Sometimes it will seem to go back to how it was when it would stick at 1600 but for the most part its better.

Im pretty confused here, is the ECU relearning how to idle because i unplugged it? I do live at 7k above sea level, and i could see it needing to learn to idle again.

Other than that, i really cant think why it would fluxuate so much.

surging idle typically indicates lean and is a symptom of a vac leak. I'd look for a leak by spraying starting fluid everywhere. a visual inspection can fail to find a leak that a flammable chemical will.

dude check your base timming as well. also our ecu's dont learn.

Hmm, base should still be at 10...

I know i want to up the base timing up to 14 but i have no timing light atm.

...

you coulda thrown something off with your splices making more resistance and possibly changeing your timming. just get a light and check borow one it only takes 2 secs.

sorry must have read over that you tried with carb cleaner

still sounds like a vac leak tho

Have you had a chance to drive the car?

Do you experience a bog on relatively cold engine by any chance around 2-3.5K RPM going from cruise to accel?

Your idle issue does sound like mine. Mine does the same thing. Goes up to 1200 or 1400 then drops down to 850. This doesn't happen all the time and goes away after driving for sometime (20-30 minutes). I noticed that when this idle issue happens the car is most likely to bog (see my Screwy Timing thread).

Just curious if you bog as well.

that sounds like a temp sensor to me.

Hmm.. it seems that temp sensor is located near CAS no?
is that the sensor used to display the temperature on the gauge as well? Cuz that seems to work just fine.

They are both next to each other, but not the same sensor.

Just curious if I moved the sensor while adjusting timing. Anyway to test it? Temp Gauge works just fine...

Hmm no bog, but same idle problem as you.

I swear theres no vaccum leaks at all...

i must be missing one- but ive been over everything a few times and still cannot find a damn vac leak...

Well i was thinkning of getting new plugs and wires as they are a good 2 years old...

Perhaps that will help.

Again today i checked the whole system for leaks, with carb cleaner(2 more cans, lol) No luck..

Did some searching....

IAC valve??!?!

Im running out of options, lol.

Ben might be onto something.
At cold your car runs richer. So if the sensor says your car is cold, ur will get a lil extra shot of fuel.
I haven't had a chance to check it out, but the sensor is not too far from CAS that i was fiddling with, maybe i "touched it"...
Let me know if you come across anything. I think we have very similar issues.

<dammit beasty, why'd you have to edit your post and make me remove the dancing gay smiley>


I had a lean hesitation that occured around 2700 rpm in vac with light throttle application. It was a lean spot, caused by a fault in the afm. cured by geting a new (used) afm. Well, actually cured by the EMU and afm delete, but still.

this is one of those cases when a wideband is worth its weight in gold.

Is your BOV venting to atmosphere? I have the exact same idle problem you do. If i put my hand over the BOV outlet at idle, my surging problem goes away. I'll get around to routing it back to the vacuum side of the charge pipes one day. I'm just to lazy to be bothered with a little screwy idle right now. :) Not sure if the TypeS has that problem though.

Give credit where credit is due.. :-)