99 Regal LS stalled now won't start

I hope someone can help with this problem because I have a couple mechanics could not. My car started and drove fine. When I came out of the store to drive home it started, but was chugging bad and then stalled. It did this a few times and then started and ran fine. Later in the day when I tried to start it, it did the chugging and stalling thing again. Now it will turn over, but won't start. I had a similar issue about a year ago and 2 mechanics couldn't seem to figure it out, but it "went away" until now. The MAF was replaced and I think they cleaned carbon out of some other part that I do not remember at this time. The engine is getting spark and there seems to be gas in the rail (full tank). I read online that it could be the crankshaft position sensor. Does this sound like it could be the problem? If so, can anyone tell me where it is located and how to replace it? Any ideas and/or advice would be appreciated.

Matt

Welcome to AF.

Crank position sensor is possible but normally the car will start and run fine but then abruptly stall at bad times while driving. It is located behind the harmonic balancer pulley passenger side of engine. Also, you may get a trac off light during the stall and the tach may act up of drop off so check that out.

Are you sure fuel pressure is good at the front fuel rail testing it with a fuel pressure tester? At least 42 psi minimum?

To check if its a fuel problem spray some carb cleaner into the throttle body , then try to star it right away, as for the crank shaft positioner you shoud not have spark, sounds more like the ignition module, most parts store can test it for you

You're upper intake manifold may be starting to fail. This allows coolant into the combustion chamber. Have you noticed excessive steam coming out of the exhaust? Is the coolant level low? If the answer to either of those questions is yes then you should remove the spark plugs & see if they're wet with coolant. You could also remove the air filter housing & see if there's coolant inside.

If everything above looks ok then here's what you need to check for a no-start condition:

Spark at all three coils. You can remove the spark plug wires from one coil at a time & watch for spark while someone cranks over the engine. The spark should be strong enough to jump from one post to the other. Check all three. If you have spark the crank sensor is probably fine.

Check for fuel at the rail. Turn the key to run a few times & then press in on the schrader valve. The fuel should spray out not dribble out. Position your hands so the fuel can't spray you in the face.

Check for fuel injector pulse. You can purchase a node light or use a #194 light bulb. Just remove the wiring connector from an injector & connect the node light or pull the wires away from the base of the #194 bulb & insert. Watch for the bulb to pulse as someone cranks over the engine.

If you still haven't found anything wrong try starting with the MAF sensor unplugged. If it still won't start I'd pull the plugs & see if they're wet, dry, black or white. Let us know what you find.

as for the crank shaft positioner you shoud not have spark

:confused:

Not necessarily on the Series II 3800 engine. You can have good spark, the car will start and the crank sensor can still be bad. Reason is it is a two in one Hall effects sensor. One side is for the 18/24X pulses and the other the 3X. On this engine it is uncommon to have a defective crank sensor cause a no start condition due to no spark. The typical failure is car will start and run but stall out abruptly at an inconvenient time. Also, accompanied by tach acting up and the TRAC OFF light coming on at stall.

Thanks for the info and advice. I was incorrect to think that the problem was the same as my previous problem a year or so ago. I sprayed started fluid into the intake and it fired for a second so no fuel getting in the cylinders seems to be the problem. This is particularly annoying since I filled the tank the night before this problem happened, but of course right. If my tank was really low before I filled it, is it possible the crud from the tank clogged the filter? I've never checked fuel pressure or changed a fuel filter, but I'm willing to give it a shot. One of the guys from auto zone (where the car actually stalled) said he couldn't hear the pump when I tried to turn the car over, but I have never heard the pump so I don't know. Looks like I have some work to do.

There's a few things that can prevent fuel from reaching the cylinders, that's why you need to check both the pressure & fuel injector pulse. If you don't have fuel pressure it could be a bad pump, relay, ground or filter. It's somewhat common for the ground bus to corrode on the Bonnevilles & LeSabres. I don't know if the Regals also have that problem.

Problem solved. It was the fuel pump. Had it and the fuel filter replaced. Car runs great so far. It's a 99 so who knows what will pop up next?