'89 Cavalier stalls while idling

[89cavalier]

Hi. I have an '89 Cavalier 2.0L 4cyl. automative. Lately when I drive it, it will stall while I am idling at a red light. It starts again with no probs, but I have to keep a foot on the gas to keep it from stalling. While in park it will idle fast and then slow as well. Finally once this week I had antifreeze leaking from under my dash near my glove compartment (I'm not sure if this is related to the stalling prob or not - my guess is the heater core). Any suggestions?

[public]

The heater core is bad. This is unrelated to the stalling. For the stalling I would start with a good cleaning of the throttle body and related componients. A new set of plugs wounldn't hurt. Good luck.

[scrt79]

check out your I.A.C. motor (control) they tend to go quite frequently, especially if you have to keep you foot on the gas to keep it from stalling.

[public]

Yes, the IAC valve is located on the front side of the throttle body. It is held on by two torx screws. Be sure to clean the valve seat inside the hole as well. You can use an old toothbrush with some carb cleaner. It works wonders.Be carefull, move the valve pentle( the pointed thing) in or out you must follow a preceedure to reset it. The car will idle very fast. You will then need to drive the vehicle at 35 mph for a couple of minutes (until it reaches temprature). You will feel when the idle returns to normal. Good Luck.

[90z24]

One other thing to consider... Did you lose battery voltage recently? Did you disconect the battery for any reason? My '90 Z24 was acting this same way and I discovered a service bulletin which detailed an "Idle Learn Procedure" you must do following any removal of power from the ECM.

[public]

I have removed the battery several times over the years and had no relearn problems. However these cars will not idle with the battery disconnected so a bad battery connection will cause them to idle very poorly.

[89cavalier]

What does the IAC value look like. I used some carb cleaner on my "carb" with some improvement in the idling but it still stalls.

[public]

The IAC Valve is on the front of the Throttle Body (looks like a carb) It has two torx screws holding it and one electrical plug on the end. Once unscrewed you will need to twist it to remove it. Make sure you dont lose the O ring. Good Luck.

[89cavalier]

I cleaned my IAC part but my car still stalls. Would you recommend replacing that part or trying something else? My car bogs/runs rough at low speeds (if I'm driving under 40 km or so). The engine light comes on ever time I'm idling in drive.

[public]

There is a proceedure for checking the IAC Valve, check a Haynes manual. Another thing, have you checked your Throttle Position Sensor? You may also want to remove and clean the fuel injector. You can remove the cover and observe the spray pattern while running. If you see any droplets or uneven spray try cleaning with carb cleaner and a toothbrush or you can replace the injector for about $60 ouch. Have you checked for vacuum leaks? A vacuum leak will almost always effect idle.

[89cavalier]

Where exactly are the throttle position sensor and the injector located?
How do I check for vacuum leaks? The past couple of days my car is really hard to drive - when I push the gas it doesn't want to go (kinda like when you run out of gas) If i give it more gas and once it reaches 50 km or so it is better.

[public]

You REALLY need a Haynes manual. The fuel injector is under the throttle body cover (black metal thing where the rubber air snorkle hooks on). It has one torx 20 screw on the back. Loosen and then you can lift the cover off. Get someone who know cars a little to help you, You will be around gas and with the cover off you can get a fire if the engine misfires. The Throttle position sensor is right around the side from the IAC you cleaned earlier. It is opposite from where the throttle cable attaches.

As for checking for vacuum leaks, get a length of hose and hold it to your ear, then with the engine running, move it around following the vacuum hoses. If you have a leak and get near it you will hear the rushing air. If you live near an Autozone you can get a loaner vacuum gague. Following the instructions it can be a better way to find a vacuum leak.