Throttle sticks after driving awhile

[IgoVroom]

When I first start my car it’s fine but after I drive it awhile, usually about 10-20 minutes the idle slowly works its way up to 3-4k rpm’s. After looking around on the forums I noticed that if I open the hood and push the throttle closed manually it goes back down to normal. I also can’t get it to stick when I play with it from under the hood.

My thinking was that since it only sticks after I drive it a lot, it’s probably not the throttle plate itself but the cabling going to it. Does that sound right or does anyone have idea’s on how to fix it? I have a loud exhaust so it’s getting to be pretty embarrassing…It’s so bad I can let the clutch out in second gear and never touch the gas pedal but still start moving down the road.

 

[billys90tsi]

spray some cable lube on it.

 

[selser420]

I had the same problem with my 1g. Its the cable housing tightening up when it gets hot. I adjusted the cable bracket a little bit towards the TB and its been good ever since.

 

[Highbooost]

Buy a non cruise cable. $50 dealer new

 

[IgoVroom]

Ok well I tried some lube it didn’t help.

I tried pushing the throttle closed again yesterday to get it to idle low, but this time the idle would only stay down while I was holding it closed...when I let go it moved back up. So now I’m not sure if it’s the cabling.

My CEL came on the way home, so I stopped at advanced auto and got the codes. Its p0420 catalyst efficiency which I’m sure is because I don’t have a cat, and p1400 Manufacturer control auxiliary emission controls.

I’ve been reading that it’s from the MDP (http://members.shaw.ca/dsm.1000q/Engineprimer/2G/mdp.htm) which I tried cleaning and didn’t seem to help.

My question is what now? I heard that blocking off the EGR can cause this same error code but I also read that it can make it go away…is that something I want to do? Or should I just spend the money on a new MDP? Can a faulty MDP sensor be the cause of my high idle or is it unrelated?

Thanks.

 

[zippyshoe]

I think there is a spring on the throttle body close to where the throttle cable connects to it. This spring returns the throttle plate to the closed position when you release the throttle cable (i.e., when you let off the gas.) Perhaps this spring is defective or worn and is no longer fully closing the throttle plate when you let off the gas.

 

[IgoVroom]

but it only does it after it's warm and has been drivin?

I guess im just wondering if the p1400 code could be the reason its idling so high. I'm about to just say screw it and give this weeks paycheck to mitsu

 

[CvicKila02]

IgoVroom don't feel bad my car is doing the same thing and it is pissing me off. I don't know what to do I replaced the TB with a used one a while ago and it was good for about 3 months now its doing the same thing. Have you figured out a solution because I can't seem to come up with one.

 

[IgoVroom]

The dealer just told me $1500 to replace the air idle control thingy. If it's what I’m thinking it's like two screws and a part that fits in my hand? I see one on ebay for $50. They also wanted $600 for a windshield wiper motor.

I told them to f*ck off... I'll let you know if it works.

 

[IgoVroom]

It didn't work...maybe because i got a used iac...maybe it's because the dealership ripped me off. But I did notice they stripped out my idle set screw.

 

[playitlouddsm]

My car was doing the same thing for a while and it was just the throttle cable bracket that bolts to the intake manifold. I had the bolts too tight and when the motor warmed up they would tighten even more, so i just loosened the bolts some and now it works just fine. Hopefully this might be some help to you.
-Nick

 

[kikkinbac]

I am also having this problem. If anyone finds the answer please let me know or post it here. I will however in the meantime try the couple of suggestions mentioned here and see if that solves anything.

 

[KILLAGST]

ive had the same problem for about a year now and i did what selser420 did and it seems to be working

 

[markGSX]

in my case the throttle cable was getting stuck right at the firewall
http://www.dsmtuners.com/forums/showthread.php?t=211242

 

[Tsi_User]

Since we're on the topic of throttle cables also, I too get throttle hang, but now it seems much harder to actually press the gas pedal down compared to two of my other friend's first gens. Should I just look for a throttle cable or what?

 

[99gst_racer]

This happened to me once too.....

http://www.dsmtuners.com/forums/showthread.php?t=185222

(post #8 was the fix)