Idle and Ignition Trouble

[OldsManiac1990]

My car is a 1990 Oldsmobile Delta 88 Royale Brougham with a 3.8L GM motor. The car is having trouble with idling(low a lot, need to hold gas pedal) and the codes from the computer come as follows:

14=Coolant Sensor read 282 for a time
24=VSS found speedometer measured below 3mph while car was in 4th gear(overdrive)
41=Cam Position Sensor(magnet is missing)
42=The EST signal did not change when the ECM applied bypass voltage to the ignition module.

I have replaced the coil and module, as they flat out failed.
The battery has low capacity, but can start the car.
There is a new Idle Air Control valve as well.

Thanks!

[maxwedge]

well for sure check the connections at the temp sensor, if OK replace it, Check this link http://www.pontiacbonnevilleclub.com.../topic745.html

[OldsManiac1990]

Hey thanks for the link to the tutorial. I didn't realize that could be serviced in that way, I will do that so I can change the timing chain as well as the magnet. Thanks. And from another place I consulted, the ECM may have bad wiring to the systems or vice versa or the ECM is going bad. I will do a short test, make sure no shorts. And then maybe switch out ECM(I have an extra lying around.)

[OldsManiac1990]

Hey everyone, my issue is fixed now. I figured it best to inform everyone how and why.

So as you read about my problem, I decided to put in a different computer I salvaged for free(aren't I lucky?) and put in my PROM from my computer. Instantly my problems were fixed. My guess is something in the computer was shorting or a bad connection of some kind. Fortunately in the year range and make of Olds, buick, etc. the computers are compatible basically 88-92 or so across many models. And now my car works PERFECTLY and I only get my code for the camshaft sensor, which I will fix in the future.

But if you have a similar problem, do consider the possibility of the wiring from the sensor, in my case coolant temperature sensor, being bad and having a short or bad connection.

[maxwedge]

Good deal

[ol mechanic]

I replaced many, many ecm's to repair code 42, often accompanied by 2 or more other codes.

[Tech II]

Late 80's to early 90's ECMs were bad......even the remans right out of the box.....