'89 LeSabre Problems

Ill get to it...When sitting for 6+ hours the car is not only hard to start but requires warm up time even on a warm day. If I do not wait until its ready to go, it'll hesitate so bad it sometimes will stall. When the car is between 60-100km/h the "Service Engine" light will usually come on. I have replaced the spark plugs, fuel filter, oxygen sensor. Usually I would use "electronic troubleshooting" to find the problem, but in the autmotive book I have purchased there is no procedure for doing it. If anyone can link me to a site that shows the procedure and codes it would be greatly appreciated. If that is not possible, a short discription on here would work also. If u have any idea what the problem might be, please respond.

Thank you for your time. Adam.

The following link tells how to pull the computer codes off GM vehicles:


http://www.geocities.com/dann8785/serviceenginesoon.html

The procedure is simple - jump two pinouts in a connector located under the dash under the radio and turn the ignition to "on" to get diagnostic mode.

That seems to be the problem. (Quad Driver Circuit). Though I have no idea what one is, and all it says is consult with your dealer. This would be my last resort. If u have any idea what it is, and if its possible to change easily..or if I should turn to a mechanic and spend a fortune.

Thank you again, Adam.

A quad driver works like a relay inside the PCM that can sense a short and trip like a breaker.

Quad/Output Driver Module:
The Control Module in your vehicle controls most components with electronic switches which complete a ground circuit when turned on.
When the switches are arranged in groups of 4, they can independently control up to 4 outputs and are called Quad Drivers.
When the switches are arranged in groups of 7, they can independently control up to 7 outputs and are called Output Drivers.
Not all outputs are always used.
You would need to find out what items are being driven by the Quad Driver that set the code. This code usually sets when there is a voltage fault on the particular Quad Driver due to a bad relay or solenoid for whatever is being run off the driver. It could be a TCC solenoid, A/C relay, lot’s of possibilities.

Just one more thing. It sounds to me like this diagnosis its giving me wouldnt be what the problem is in the first place. The hesitation and stalling...and with such a vast array of possibilities for what is causing the light, is it worth doing the testing? or just to continue with trying to find the root of my hesitaion/stalling problem?

Thanks again, Adam.

If the coolant tempature sensor is at fault and the PCM thinks the engine is always warm, it will not go into a cold start mode. Cold start mode is like a choke on the old cars. The injected cars use the coolant temp info to richen or lean injectors.

That sounds like it may be the problem, but wouldnt it have shown up when I did a diagnosis test? I will check the sensor anyway to be sure.

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