1990 Buick Century...Stalling and Turning Back On

No, not until you give us a logical explanation of the events leading up to this failure.

Have you replaced the fuel pump and fuel filter?

The symptoms resemble vapor lock.

i agree. the solution would be to insulate the fuel delivery system from heat sources.

I am having a sale on ignition switches. Not any worse a guess than the crank sensor, and at least I can unload these switches.

Or, you could test the car, and determine what is failing.

Does the car have spark when it will not run?

If you pour some gasoline into the air intake, will it restart?

Do you get the "check engine" light to come on while driving?

Have you had the OBDII codes read?

Or try one of my ignition switches.

Wow! What a novel concept. Troubleshoot the problem, and replace only the parts necessary to fix it. This new procedure could turnout to be less costly and time consuming than replacing random parts until the problem disappears. GA Bob!

Your oil return ports are clogged. That year and other years around that time are notorious for the ports being under drilled. Clear the ports and see if that helps.

Good luck

While cleaning out the plugged oil ports may solve the problem, I suggest you check your blinker fluid, and muffler bearings for pre-mature wear.

Long ago I worked at a shop as a mechanic, and learned a few things. Regardless of how many random parts get changed, the problem may never get fixed unless a proper inspection, testing, troubleshooting, code reading is accomplished. I know far too many people who just start throwing parts at a project til (if) it gets fixed... This tends to be very costly.

We had a Chevy Van with a 350 come into the shop one day that was having trouble running. It was backfiring, and coughing out the intake nearly at the same time, which was odd. One of the other guys in the shop had begun the project (he was not the brightest crayon in the box) and had begun by removing the carburetor to have it re-built... which at first thought seemed reasonable. He tossed a fresh carb on the engine, and the exact same symptoms occurred. "Well it's not the carb" was his response.

He then decided to change out a number of the emission sensors... none of them solved the problem. He tinkered with that van for over a week, with no success.

He became frustrated with the job, and stopped working on it, to spend his time on other projects that did not need troubleshooting. Being the lowest on the totem pole, I was delegated to fix the (now torn apart) Van. The Engine was already torn down, exposing valves, timing chain etc. We already had a rebuild kit ordered, so I began to rebuild the engine (based on the previous mechanics lack of troubleshooting, he suspected that a rebuild was all that was left to do). After a fresh rebuild, i proceeded to fire it up... Same exact issues, coughing/backfiring.

So now, we had replaced darn near everything that could be causing the issue... And later I learned, that so did the last mechanics that had this van, they had installed a new distributor, plugs/wires, filters etc etc etc... so now I was scratching my head. As a last resort (should have been the FIRST thing done) I decided to hook the van up to some monitoring equipment to communicate with the computer. One of the pieces of equipment was a scope hooked to the ignition system to check the ignition... It seemed to not be working correctly, as I was not seeing spark at the proper intervals. This was suspect. After further investigation, it turned out that the previous mechanic (parts changer) had replaced the original distributor, and had replaced it with a distributor made for a 6 cylinder! I could not believe the engine was running albeit poorly.

I ordered up a new distributor for a 350 V8, installed it, fired up the van and it ran like a top. Now that the customer had a bill for well over the value of the van, and a completely rebuilt engine with all new emission equipment.

In the end, this $5000 bill should have cost no more than a few hundred bucks, and the real problem was a mechanic who just began changing parts without doing a proper troubleshoot.

Don't change anything unless you KNOW it is the culprit, and have done some troubleshooting first. (exception to easily/cheaply replaced maintenance items, such as filters/fluids/wires)

Parts changers just cost everyone money and time.

HEY! STOP IT!

I need to unload these obsolete ignition switches.

One time I was helping a friend with a Buick 225 V6 in a boat. He had replaced the points, condenser, rotor, cap, wires plugs and filter. It would start easily, idle well, and never sputter or buck. But had so little power, it could not get on plane. Timing was good. Fuel pressure and level were good. We pulled the plugs to check compression, and ground 3 plugs not firing. It turned out that when he changed the points and condenser, he had pulled the wire that ran to the coil. He had also dropped one of the rotor screws, so he just got another one that fit. Now the longer screw would touch the wire for the coil when ever it passed. That would kill whatever cylinder that was firing at the time. That worked out to every other cylinder in the firing order. Just pulling the wire back in place, and all was well. Ever since then, I always recommend a new ignition switch to all.