# high idle, 16v 2.0 cis-e



## rub (May 15, 2005)

Hopefully will get someone to figure out the source of the problem here, as this has got a couple people stumped. 

I replaced the intake manifold with a 50mm euro one about a month ago. Since then, ran about 3 weeks without issues, idled solid at 900. The last week, the idle has gone from around 900 to 1800/1900. 

Checked the first possible cause: vacuum leak. Found no leak anywhere when going over vacuum lines with throttle body cleaner. Also sprayed around the injector seats and all gaskets (upper/lower intake, throttle body) to check for leak, no luck. Checked the idle air stabilizer valve by disconnecting and plugging up the hoses. Nothing changed when plugging up the hoses. Also checked throttle cable, and nothing is stuck causing the throttle to stick open. 

What am I missing? thanks for any help...


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## jasmind (Mar 8, 2007)

i have the same problem, 8v gti ke-jet , checked everything per bentley. when i turn the idle screw all the way in it drops do 1300 rpm. when i clamp the ISV hoses nothing happens. I'm stumped


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## ellocolindo (Jan 15, 2010)

i have a few 9a in passats. last time i had the high idle issue turned out to be a failing isv. i replaced with a used one and problem went away.
what car is this on?
do you have a scanner for it?
check the functional test and listen for the isv to cycle.
if no scanner.
check the resting point of the idle switch on the throtle body. on one of my cars it would come loose everytime i revved over 3500 rpms due to engine vibrations.
after that i had to stop at every light; pop the hood and reset that by hand all the way in.
worth looking into that little screw....:laugh:


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## jasmind (Mar 8, 2007)

9A is CIS-Motronic, different ISV is used with cis-e, three wire, and no screw


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## rub (May 15, 2005)

Sorry for the long time on follow up (been out of the country and then slammed with work the second I got back) 

- Anyways, it ended up just being the idle adjustment screw on the throttle body. I guess when I reinstalled the throttle body after putting on the euro intake, the throttle body cleaner also ended up lubricating the adjustment screw to the point it vibrates lose after getting on the throttle hard for a while. A little thread lock did the trick. Initially I never thought of touching the idle adjustment screw as in the Bentley manual it states not to change this. Conveniently I overlooked that this statement only applied to the later cis-motronic models. wooops.


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