Mechanics

91 3.3 STARTS AND RUNS NORMAL COLD, BUT DIES WARM.

1991 Buick Century

Engine Mechanical problem
1991 Buick Century 6 cyl Front Wheel Drive Automatic 189195 miles

Hello, hope you can help. I just had another problem happen. Yesterday I was accelerating, about 25% throttle, and around 45MPH the car just flat out stalled, like I turned the key right off. I pulled over, tried to start it, and it would not start, it just would turn over and over and over. I checked simple things, heard the fuel pump priming, have fuel at the fuel rail. I got it towed back to my house, let it sit for a couple of hours while it cooled off, and went to start it back up again, and it started and ran 100% normal. I let it idle for 10-15 mins, then I revved the gas a couple of times, and it just stalled out, like I again cut the ignition off. No amount of pumping/flooring will get it to idle back. I tired to start it, and it starts and stalls right out. Let it cool off, and again, it will start, rev, drive, great, but only for a couple of miles. Once it gets warm it just dies right out. Im thinking Crank Position Sensor, but it seems pretty involved to change, so want to make sure. Thanks all.
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1991Century3.3
July 13, 2010.




Sounds like heat related issue-Check and monitor the fuel pressure to rule out the fuel pump if okay -If you want you can check and test the coils and the ignition control module before the CPS
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Tiny
Rasmataz
Jul 13, 2010.
Well I do have a couple of videos.

Here is the first one as it was warming up, and you can hear how it just flat out stalls when revved. The knocking is the idler pulley going bad. Also It idles low, so you had to very gingerly let up on the throttle or else it would idle to low and stall. No amount of flooring/pumping will get it to idle back.

Dont know how the starter did not over heat.

Tiny
1991Century3.3
Jul 13, 2010.
Hook up a fuel pressure gauge and check the fuel pressure if its within specs. The fuel pressure should be 41-47psi if okay clean out the idle air control valve and EGR valve and test the throttle position sensor and manifold absolute pressure sensor let me know what's happening

Tiny
Rasmataz
Jul 13, 2010.
Here is a youtube video of what its doing. Much better then me trying to type it out.

http://www.youtube.com/watch?v=XHDEiZVlwSA

Thanks.

Tiny
1991Century3.3
Aug 3, 2010.
So today I was again checking my spark, and it seems as I have a weak coil pack. 2 of the coil packs have a nice blue strong spark that will arc over 1 1/2 inches, the 3rd coil pack will will no spark unless you are less then a 1/4 inch away from ground. Also with a spark plug disconnected on this coil, I feel NO difference. Same misfire, stumbling, no power. If I disconnect both spark plugs off this coil pack, I can then hear popping in the intake. So im off to buy 3 new coil packs. Wish mE LUCK. : Us:

Tiny
1991Century3.3
Aug 4, 2010.
Well, I replaced 3 coils, and she ran GREAT, no missing, great power, all of the above. About 15-20 mins pass im driving going back home, and give it a couple WOT runs, and she dies both times, again right at the peak of the wot run like I turned the key off. But it starts up, and is alright if I do not give more then 75% throttle I would say. About this time I hear the fuel pumping making all kinds of noise, from a very loud hum that you can hear 15 feet away to a weak sounding electric motor. I get back in my driveway and she sputters and then dies like I ran out of gas and will NOT start. I pull out the starting fluid and she fires right up for about 2 secs. Just for the hell of it, I check for spark, and have 6 NICE blue strong spark that will spark better then 2 inches. Let the car sit for 45 mins, and she starts and purrs nice, but slowly hear the loud hum returning with in a couple of mins. So tomorrow im going to drop the tank, and replace the fuel pump and strainer. I just replaced the fuel filter 15 miles ago. So hope this will solve all problems. Also should note, I cut open the old filter, and it had very fine metal glitter in it. Very fine, smaller then pepper flakes.

Tiny
1991Century3.3
Aug 5, 2010.
I dont know if this helps, but I had the exact same problem with the exact same car. I put in a fuel pump, PCM, crank sensor. It wound up being a shorted fuel injector, it only failed during certain times, like WOT excursions, I replaced the injectors with some BMW injectors from a 2.5 liter M-20 "I" motor and the problem went away and did not come back. So if the fuel pump fixes it, good. If not, you might want to try my solution.

Dr. Hagerty
Aug 6, 2010.
Hey now. New fuel pump and strainer installed, and she runs great. Had to drop the tank, and boy I dont want to do it again anytime soon. So I had 2 issues. The bad coil packs for the misfire, and a weak fuel pump for the stalling, and not starting unless cooled off. Happy shes running again. Already put 80+ miles on it. : Us: thanks again for the ideas.

Tiny
1991Century3.3
Aug 6, 2010.

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