Mechanics

ROUGH IDLE OR STOPPING COLD START

1995 Geo Prizm • FWD Automatic •

I have a 95 geo prizm and when I first start the car it will run rough and cut out if I take the foot off the gas. What I do is keep one foot on the brake and one foot on the gas and get it out on the road. Once it is rolling I take the foot off the gas and it will idle really low but not cut out. Then it is safe to stop at stop signs etc. When the engine is warm there are no problems. It does seem like I might have a slight coolant leak so I am wondering if coolant leaking in might be a problem. Also I was reading somewhere that a defective coil pack might be the problem. I have asked other mechanics about this and it basically stumps them
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Brantcoyle
March 4, 2011.



Yes rough idle at cold start. And coolant loss indicates that coolant is getting into the cylinder and runs rough util he spark plugs burn the antifreeze off. I would have the coolant prob repaired and also have the iac motor checked. This is the sensor that controls how high or how low the car will idle.

Billymac
Mar 4, 2011.
What do you think of that stuff you put in your radiator that is supposed to stop coolant leaks? My friend used some and it worked but now seems to be blocking his heater core a bit. Its not a huge problem because it always starts and once you get it running down the road a few feet the idle wont get so low that it quits on you. It does play havoc on the brakes though since I have to use one foot on the gas one foot on the brake to get it in postion to run down the road.

Tiny
Brantcoyle
Mar 5, 2011.
Well the stop leak is kind of bittersweet it will usually stop leaks. But it will plug heater cores and therm stats. So I would say if not too big of a prob why chance adding more. Good luck

Billymac
Mar 6, 2011.