Idle sporadically racing on '97 Metro Hatchback with 1.3L

[Hacksaw]

Good day people,
I have a new car and a new problem. The idle raises to maybe 2000-2500 rpm out of the blue, stays there, and then falls back to normal. It will do it while the automatic trans is in gear as well and will overcome the brakes and lurch forward at stoplights...scary. I've only owned the car since last night so I am still familierizing myself with her. Does anyone have experience with this problem on their 1.3L engine? The guy I bought it from has thrown a TON of parts at it, but still no resolution...

Hacksaw.

[SVOboy]

Perhaps the throttle is sticking open? Or some obscene vacuum leak?

[Johnny Mullet]

1.3L huh? I am not familiar with those, but I would check for vacuum leaks and also make sure the TPS is working or adjusted properly.

[jjackstone]

Had a friend similar problem on a '94. I believe he ended up swapping out the ECU to fix it. I believe a Scan Gauge might generate an error code for this condition if you have access to one.
JJ

[Hacksaw]

Yeah, would've messed with it yesterday, but couldn't get the hood open on her. I didn't really try to get it from underneath or anything, just that the cable wouldn't release the mechanism...so I started to clean it out instead. I bought the thing Saturday night for my daughter who wanted a Metro like mine, but an automatic. I tried to teach her to drive a stick, and she did fairly well...she just wants to learn to DRIVE first. She's still in the permit stage and has yet to take the "Segment 2" class of drivers training.

I'm thankful for your suggestions so far and continue to welcome more...
I know the guy changed the ECM, throttle body, vacuum lines, and TPS without results.

[Johnny Mullet]

There is a certain adjusting procedure for the TPS where the engine has to be warm and a feeler gauge is used, but I can't find the link on TeamSwift.net right now.