2 idle revs

[minimikee]

Hey all,
Last night I went for a drive after my suspension, I got the idle set right just below 1000RPM when it was warm, did all the right things and no more dramas ... until later

It started to idle at 1750RPM randomly and would pull the car along in gear. If i touched the accelerator slightly, just a blip the revs would drop back to the other idle until you get it back up over 1750 and it would idle there again until I blipped the throttle again.

I turned the car off and back on again and the problem went away for a while then just came back.

Any ideas what the problem is??

[Habibosaurus]

 Sticky accelerator cable/idle meter

[minimikee]

nope, throttle closes properly everytime, i spent a lot of time adjusting the cable. the idle switch seems to work

[Jecks]

loosing compression in the head??

[minimikee]

i did a compression test, it pulls equal numbers on all cylinders, quite happy with that lol

Would compression loss have those symptoms though??

[Unbalanced_]

Ive got a very similar prob in my car at the moment. Would be interested to know what the cause is.

[rathies]

hmm I used to have this problem with my auto trx it was a pain. I dare say your Auxillary Air Control valve is on its way out, it could even just be a dirty plug.
My current trx has a working netural switch and whenever it goes out of netural the revs automatically go upto 1500rpm. so that sheds light on the engines ability to raise the revs on its own.

[noss]

yep, clean the AAV (auxilary air) as rathies said.. i have also had a similar problem when i had a leak in my intake (had a hole in a silicone joiner) because the ecu would think there is xx amount of air but in fact yy air was getting in (because of the leak) and it leaned out the motor which resulted in higher revs.

but considering the 750rpm difference, that would more than likely be the AAV

[minimikee]

so just disassemble the whole AAC or just pull the solenoid off??

[Kranzy]

Take off the four allen key bolts that hold it in. Take care not to destroy the gasket, remove that and clean the inside so its spotless. Make sure the spring in there can move freely.

Install and see if you've fixed your problem.

[minimikee]

done and done.

I'll post up the results tonight.

Thanks guys

[rathies]

clean the plug with contact cleaner really well too! When I took my car to have a shitload of mechanical work done the douchebags snapped the whole connector off the aac..and just pushed it back on. I couldn't for the life of me figure out the 200rpm (yes 200rpm) idle until I started playing with it.

[minimikee]

wow 200RPM, mine stalls out when i pull the AAC off