1991 Olds Reg Elite stall at operating temp

[danbrwn]

Have read several posts regarding this issue but have yet to see anyone say what if anything actually fixed this problem, so here goes another post. I have a 1991 Old 98 Reg Elite with the 3800 engine, No EGR valve (plenum), new plugs, wires, waterpump, oxygen sensor. Runs absolutely great until it gets up to around 200 degrees (analog gages so maybe inaccurate), stalls at speed, trys to start but will not until engine cools back down. Right now I will just turn on the heater to pull some heat out and will start back up and run as long as I keep the temp below this trigger point. Several post have suggested the Crank Position sensor. Has this resolved this problem for anyone else? Are there diagnostics for the sensor that I can perform with a meter? Please help as I live in the south and the heater solution is really hurting right now. Thanks

[maxwedge]

Originally Posted by danbrwn

Have read several posts regarding this issue but have yet to see anyone say what if anything actually fixed this problem, so here goes another post. I have a 1991 Old 98 Reg Elite with the 3800 engine, No EGR valve (plenum), new plugs, wires, waterpump, oxygen sensor. Runs absolutely great until it gets up to around 200 degrees (analog gages so maybe inaccurate), stalls at speed, trys to start but will not until engine cools back down. Right now I will just turn on the heater to pull some heat out and will start back up and run as long as I keep the temp below this trigger point. Several post have suggested the Crank Position sensor. Has this resolved this problem for anyone else? Are there diagnostics for the sensor that I can perform with a meter? Please help as I live in the south and the heater solution is really hurting right now. Thanks

See if you have spark and injector pulse during the event if not the ckps is most likely the problem but wiring to the icm and /or the icm could also cause this.

[danbrwn]

How do I check the injector pulse?

[maxwedge]

Originally Posted by danbrwn

How do I check the injector pulse?

Noid lite kit, usually about 25$, plug it into an injector connector, crank the engine see if it flashes, if so the pcm is pulsing the injectors if not search goes on.

[danbrwn]

Definitely does not appear to have any spark during event. Have not purchased the noid kit yet. Hope to avoid if possible. I ran the car until op temp, checked with timing lite to see if firing, not firing. Bled a little heat off with heater , started right up. Is it absolutely necessary to see if the injectors are firing? Or can I be reasonably sure the crank sensor is bad. It appears to be a pretty nasty little job to replace the crank sensor. Anyway, thanks for your help. Dan

[danbrwn]

Since I have seen a lot of post for this problem with no one ever really saying if, and what got them going, Here is my experience. I have my car running again. Eventually the car just quit running at all regardless of temperature. I replaced crank sensor, cam sensor, and finally ignition module. Ignition module appears to be the problem although I can't rule out a combination problem. Some quick thoughts, if you are going to replace sensors as a starting point. I would suggest trying the camshafts sensor first since it is easy to get to, low cost ($20) and may fix things. I would probably take the ignition module off and have it checked at Autozone early in the process, although I did not know at the time that they have a tester. I hear mixed reviews on the effectiveness of the tester, so use with caution. The crank sensor is a bit of a bear since you have to take the harmonic balancer off. The haynes manual says you don't need a puller, you definitely do need a puller. Once the sensor is put on, you will have to put the harmonic balancer back on partially so you can line up the fins on the harmonic balancer so they do not hit the sensor. I put it on part of the way then got beneath and moved the sensor in and out until there was about a .020 inch gap all around. I used a feeler gauge to do this. Then tighten the screw that holds the sensor in place and put the harmonic balancer back on. I hope this helps. Dan

[lrshingle]

Hello,
I Have An '87 Olds 88 With The Same Problem. Read A Lot Of Posts Regarding Possible Problems. Mine Has The Same Symptoms As Yours. If You Have Not Yet Found The Problem. Try This. Let The Engine Run Until It Stops Itself. Like Mine This Will Be Right After It Reaches Operating Temp. Trickle A Little Cool Water Behind The Harmonic Balancer Onto The Crank Position Sensor And If It's Starts Back Up Like Mine. Wella, It's The Crank Sensor.

[rptorain]

well guys i am working on a 91 model now and i have replaced the module and coils and have also replaced the cam and crank sensors and still have the same problem as soon as this thing get warm it just dies. but i have noticed the when it dies it still has ignition but it is really weak only about 15,000kv but when it will start the kv is 50,000 plus. any of you guys have any ideas before i replace the computer.

[rptorain]

hey guys i fixed it!!!!!!!!!!!!!!!!!!!!!!!!!!! installed a remanufactured ecm. it was only $130 bucks

[rhenryjr]

Where did you buy the ECM?

[rptorain]

got the ecm at Carquest just had to switch the prom out from the old one

[Alibi]

You can pick up a remanufactured ECM on Ebay for around $50....even less if you look around a bit.

[rhenryjr]

Thanks! I may need one.