Doesn't want to run when engine temp is 220 in warm weather

I have a 1994 Buick Regal Custom 3.8L. In the winter it runs fine, no problems at all while sitting at a light or sitting and waiting at a drive-through like McDonalds or some other place. When the weather warms up a little, even if it's only 70 out and the coolant temp reaches 220, it starts to sputter, stall and doesn't want to run and it doesn't throw a check engine light. It can leave you sitting at a stop light if the traffic is congested and you have to wait too long. All I can do is sit and let it cool down unless I can get it moving fast enough to get the temp down below 220 and then it will run correctly again, but if it gets back up to 220, it will do it all over again. The thermostat has been replaced, but it did not help. There is no water in the oil.

Thank you for any help you can give. - Jamie

Welcome to AF. Many things can cause this, no magic bullet here. First thing I would do is disconnect the maf when the problem occurs and see if it runs. Second try to check for spark and/or injector pulse.

Welcome to AF. Many things can cause this, no magic bullet here. First thing I would do is disconnect the maf when the problem occurs and see if it runs. Second try to check for spark and/or injector pulse.
Thanks for the welcome. I was told by someone to let it get warm, wait for it to start missing and then pour cold water on the crankshaft position sensor to see if it stops missing. I have no idea where this part is though.

BTW, congrats on you description of the problem and info provided, we at AF wish all the posts were like this. That said, the cps is mounted to the r/s of the harmonic balancer on the front of the crank you will see the connector there.. You could also, as I said, see if you have spark when this occurs ( 2 man job). Post back the results.

Well I think it has spark because when this happens, it will sometimes keep running if you don't try to drive it. It mostly just loses power and doesn't want to go, which is why it can leave you sitting until it cools off. You can try to get it moving down the road, which sometimes works, but just misses like heck. It won't go up a hill when this happens. It's fine if you let it cool off, as long as you don't have to sit in traffic after you get it going. Also when this happens, it sounds like the timing is way advanced because the valves rattle and it spits and sputters.

I mostly have my uncle work on my cars, but have been able to do some of the simple things myself. I'm one of the few women I know of that can change a water pump. lol! I can always take it to my uncle's and put it up on his ramps and try to find the sensor, or I can just tell him where you said it's at and let him do it, but he does get pretty sore laying on the ground.

Doesn't sound like the sensor, disconnect the maf when this happens, see if it runs any better, also check the fuel pressure at the rail.

I had a similar prob that was resolved by replacing the ignition coil; seems it began to fail after it got hot.

I think I solved the problem. I found out later I should not have used carb cleaner, but oh well it worked. A couple mentioned unplugging the MAF when this happened to see if it would stop. I once owned a Mercury Villager and was on an email group where people would suggest using carb cleaner and a toothbrush to clean the little thermistor thingy. Well the two wires on the Buick sensor looked too fragile to use a toothbrush on, so I just sprayed the heck out of them with the Gunk cleaner. They did look a little black before this and more clear after spraying. I used the entire can on it.

Replaced MAF and could not duplicate the problem and the pinging stopped.

I let it sit idling for a good while to make sure the temp was where it always screws up and it still ran smooth. I even tried putting it in gear and stepping on the gas and no pinging or missing. Just before cleaning it, I was on the way to my uncles' and it was screwing up.

Hopefully the carb cleaner didn't damage it, but it seems fine now.

Carb cleaner just for the start up check is ok, otherwise there is a specific cleaner for the maf made by CRC.

Well I spoke too soon. It really screwed up today. It refused to go and I ended up sitting for a bit to let it cool down. It got to the point where it would not go up a small hill, and barely go on a flat road and sometimes surge at full throttle and then go like hell, but not always. It was just acting like it had the power of a Briggs and Stratton 3hp engine trying to push a big car. Really no power at all.

It would also get to the point where it was dying after putting it in gear or trying to run the AC. I went to my uncle's after I got it running to see if I could make it mess up and then spray the crank sensor as one mechanic suggested, but I couldn't really tell because it appears to clear up after the hood was up for a couple minutes. It was also very difficult to get to the point where it would screw up at my uncle's. It would not mess up if I left the hood up.

I unplugged the MAF when this happened and it did the same thing as when it was plugged in, but with it unplugged, the check engine light came on. After this, I cleared the code by unhooking the battery.

It is however getting better gas mileage since cleaning the MAF.

Just wanted to let everyone know that it was the crankshaft position sensor. It was even cracked. I can go to a drive thru now without it dying. :wink:



I have a 1994 Buick Regal Custom 3.8L. In the winter it runs fine, no problems at all while sitting at a light or sitting and waiting at a drive-through like McDonalds or some other place. When the weather warms up a little, even if it's only 70 out and the coolant temp reaches 220, it starts to sputter, stall and doesn't want to run and it doesn't throw a check engine light. It can leave you sitting at a stop light if the traffic is congested and you have to wait too long. All I can do is sit and let it cool down unless I can get it moving fast enough to get the temp down below 220 and then it will run correctly again, but if it gets back up to 220, it will do it all over again. The thermostat has been replaced, but it did not help. There is no water in the oil.

Thank you for any help you can give. - Jamie

Been awhile since posting about this. Just wanted to let everyone know that the crankshaft position sensor was the definitely the problem. I never had another problem with it since it was changed.

One time I was at a drive thru window at Taco Bell and it died and we had to push it. That was embarrassing.

The sensor was cracked and there was what appeared to be a little wire exposed where it was cracked. After examining it, you knew that it was the problem. The new one came from AutoZone. They matched the price of the NAPA equivalent.

I've been having problems with the car warping rotors. They were just put on new (because one was warped) not too long ago and one or more is warped again already. I don't know if the warranty coveres that or not.

Thanks for the belated feedback. Since the original problem has been resolved this thread has been closed due to the age. Start a new post on any new issue(s).