Starting Issues - Please Help

Hope you can forgive as this is not a Buick. I have a Delta 88, 3.8 "C", but suspect the engine mechanics are the same as the LeSabre. If you want to see all the details check here:

http://www.automotiveforums.com/vbulletin/showthread.php?t=474920

Summary is that I've had starting problems when cold for at least a year. In the last few weeks it has gotten much worse and currently I essentially can't start at all.

Replaced camshaft sensor to get rid of 41 code. Did not help and perhaps made it worse with some backfires on start. No other codes since.

Found vacuum line to fuel reg disconnented, and hooked it up again. Done at same time as the camshaft replacement.

Recently got much worse. Can't start. Fuel pressure is 43 psi and drops to 35 when running (when it does run!!). Fuel pressure drops sometimes when stopped - more likely when hot. However, it comes back to 43 when the ignition is turned on.

Cleaned throttle body, mass flow sensor, replaced plugs. Lifted fuel rail and could not find any injectors leaking.

Not sure what is left? Can things like the O2 sensor fail without setting a code?

Engine cranks fine, but misfires and spits the starter out. Get occasional backfire, but an actual start is a rare occurance now.

Any help appreciated,

Ron

Bad ECM?
Timing chain skipped a tooth or two?
:2cents:

Bad ECM?
Timing chain skipped a tooth or two?
:2cents:

The puzzling part is that when it starts it runs just fine. Never stalls, no hesitation, no miss, lots of power at low revs and high revs. Essentially runs perfectly. I got it to go once yesterday and took it for a drive. As usual it was just fine until I stopped it.

Would either of these issues explain the good running but hard to impossible starting?

Ron

Bad ECM?
Timing chain skipped a tooth or two?
:2cents:

Maybe the bad ECM.... but I don't think a timing chain would allow it to run as well as it does when it starts.

What year is this car?

Maybe everyone is sick if me saying "check the grounds" but that is what I'd recomend here. My 97 LeSabre had a bad ground that caused poor starter operation, (slow responce like the battery wasn't fully charged) dome lite dimming when the power lock were used. The last straw was when I held the power window switch too long after it was up. The engine died and wouldn't restart. Lucky (or was it luck) I was able to roll to my driveway.

I started checking fuses....I didn't find any bad fuese. It all turned out to be a bad ground near the battery on the body. I cleaned it up and now the starter really cranks, the dome lights don't dim with the power locks.

Have you ever seen a car on the road with one headlights dimmer than the other? I would be willing be to bet that is the cause of a bad ground.

I hope this helps. Check all wires that goto the body. You might even want to use a ohm meter to check for bad wires.

Regards

Dan

You should try and scan this when it doesn't start, do you have spark and do the injectors pulse, 2 basic tests here, or scan it and look for cranking rpms when it won't start, if none suspect crank sensor, but there are tests to be done first as I said. A cheap noid lite will check injector pulse.

Hope you can forgive as this is not a Buick. I have a Delta 88, 3.8 "C", but suspect the engine mechanics are the same as the LeSabre. If you want to see all the details check here:

http://www.automotiveforums.com/vbulletin/showthread.php?t=474920

Summary is that I've had starting problems when cold for at least a year. In the last few weeks it has gotten much worse and currently I essentially can't start at all.

Replaced camshaft sensor to get rid of 41 code. Did not help and perhaps made it worse with some backfires on start. No other codes since.

Found vacuum line to fuel reg disconnented, and hooked it up again. Done at same time as the camshaft replacement.

Recently got much worse. Can't start. Fuel pressure is 43 psi and drops to 35 when running (when it does run!!). Fuel pressure drops sometimes when stopped - more likely when hot. However, it comes back to 43 when the ignition is turned on.

Cleaned throttle body, mass flow sensor, replaced plugs. Lifted fuel rail and could not find any injectors leaking.

Not sure what is left? Can things like the O2 sensor fail without setting a code?

Engine cranks fine, but misfires and spits the starter out. Get occasional backfire, but an actual start is a rare occurance now.

Any help appreciated,

Ron

Sounds like you got your hands full with this one! As Max had pointed out, you need to find out if you're getting a signal off of the crank sensor and it doesn't sound like you had checked for a spark if I read the post correctly. A scan tool or scope will verify the signal(s) to the injector(s) and ignition system. A noid light will tell you that you're getting a signal to the injector, yet it won't tell you if the injector is shorted or open. Try checking the crank signal and if that looks okay, try looking into the ignition system.

Thanks for all the help on this. It is a 1988 Delta 88. I'm starting to think the more urgent problem is the overrunning clutch on the starter. I have lots of crank speed, but on the first fire of a cylinder the starter clutch disengages. This happens with less than one rev on the engine going by observation. The only way I can get it to crank for any length of time is by holding the throttle to the floor. I'm told that cuts all fuel off (flood clearing mode). In that mode it will crank for quite some time. I do need to check for spark and will do that, but with the short time it cranks before the starter disengages this is hard to do.

I'm currently planning to do the starter next.

Ron

Thanks for all the help on this. It is a 1988 Delta 88. I'm starting to think the more urgent problem is the overrunning clutch on the starter. I have lots of crank speed, but on the first fire of a cylinder the starter clutch disengages. This happens with less than one rev on the engine going by observation. The only way I can get it to crank for any length of time is by holding the throttle to the floor. I'm told that cuts all fuel off (flood clearing mode). In that mode it will crank for quite some time. I do need to check for spark and will do that, but with the short time it cranks before the starter disengages this is hard to do.

I'm currently planning to do the starter next.

Ron

Ron

You can get a starter drive and replace the one in your starter. While you're in there clean it up and lightly lube the starters bearings with some good grease. In my 97's starter, (I just had it out and appart) there are neddle bearings. If keeped lubed this starter will run, or should I say "start" for a very long time. Pun intended!

You should be able to save 60.00 to 80.00 on the starter.

Regards

Dan

Thanks Dan. I was wondering that. I had a Nissan truck that liked to eat starter drives. I got to the point where I could replace them in less than 15 minutes.

Ron

Thanks for the help on this. I replaced the starter drive and now it starts fine when warm. However, I suspect I still have the cold start problem. At the suggestion of another, I have checked the ignition coil resistance and found them at 16K, 25K, and 47K when cold. They improve to 14K, 14.5K, and 19K when warm. Would this be enough to make it hard to start when cold? Hope to get new coil set tomorrow.

Ron