Car actually dies twice after 13 years O' running swell.

Better take a pocketful of magnets along with you.

---Bob Gross---

Doesn't this have the crummy plastic main cog on the timing gear? It sounds like it needs timing work done, which is going to run about $700 if the timing chain cover is mangled. Chain, cogs, sensor(magnet), tensioner, camshaft button, and maybe the cover. Maybe a MAF as well, as backfiring more than a couple of times when it's that old usually shreds what's left of it.

The problem is - the chain needs to be replaced every 70-80K miles like a belt on those engines and yet they never tell you that, so people run the car until about 150K or so and then the chain is so stretched that the engine won't run or it slips a couple of teeth(or just comes off).

I got mine done - $750 total for it all, and it runs almost like new(replaced plastic and teflon parts with steel and bearing parts, so it's indestructable but a bit noisier).

In any case, it's not a job for your local mechanic - get the local GM garage to look at it as they have all the computers and sensors to properly diagnose it the first time. In my case, the two garages I went to had no idea. After two weeks of hamfisted attempts to figure it out, it took the Buick garage exactly 2 hours to figure it out and start repairs.

Joe, This engine doesn't have a nylon timing gear. It has two steel sprockets.

========= Harryface =========

1991 Pontiac Bonneville LE 3800 V6 ( C ), Black/Slate Grey _~_~_~280,385 miles_~_~_

~_~_~_~_U.S.A._~_~_~_~_~_

~~~The Former Fleet ~~~

89 Cavalier Z 24 convertible 78 Holiday 88 coupe 68 LeSabre convertible 73 Impala sedan

I gotta agree with 'Face on this one. A timing chain can pretty much last the life of the engine.

The only problem is that every decade or so GM likes to experiment with using nylon tooth timing gears to make things more quiet. The teeth usually start to fall off before 100,000 miles.

So, what do you use to brush the teeth with?

---Bob Gross---

Good. The chain is almost certainly stretched, though, and the camshaft button is likely wearing its way into the cover. My guess is that it has slipped a bit and the engine is to where it's having to do strange things with the computers to compensate.

Joe O,

After inspecting the magnet in the timing gear today, it appaers to be intact and snapped firmly into place.

The cam magnet doesn't appear like it has any rubmarks on it. Sprayed it with brake kleen & compressed air ( TIP : don't touch parts when the engine is HOT ). I think if anything was rubbing the timing cover you'd here it.

Tried a, new camshaft sensor and the SES light still remains on throwing code 41. During a 225 mile ride today the car run fine.

The Good Wrenches I know at Chevy said to tap the Crank Sensor and MAF to see if the car stalls. I banged on them both like Ricky Ricardo banging the bongos during Babbaloo. Car didn't stall.

Will see what tomorow brings............

========= Harryface =========

1991 Pontiac Bonneville LE 3800 V6 ( C ), Black/Slate Grey _~_~_~280,385 miles_~_~_

~_~_~_~_U.S.A._~_~_~_~_~_

~~~The Former Fleet ~~~

89 Cavalier Z 24 convertible 78 Holiday 88 coupe 68 LeSabre convertible 73 Impala sedan

Maybe the spark control module is getting old...

Glad to hear that it's not the timing gear. That leaves only a few choices. The MAF and EGR valve(or whatever it has for that year that recirculates exhaust during startup) might be fighting each other, or it might be something simpler like a dying coil pack or the module underneath them.

I'm amazed at the lack of feedback on the GM engines of that era. Mine is an older one and it spits back only maybe a dozen possible codes. The 2004, iirc, got the series 3 engine and a new computer/sensor package that actually gives *feedback* on all the sensors as well, so it can tell you exactly which part went bad. Quite nice.(and about time - grrr)

Joe O,

The EGR Valve was tested over a month ago by a GM tech when I was getting a different code. EGR proved to be alright during his tests, but a code 26 was stored for a quad driver fault in the ECM. Replaced the ECM & the problem went away.

The code 41 was erased by the tech, but the light cam e back on. It has been going off & on since February. As of last week the light is on constantly.

EGR & MAF & Ignition Module & Injectors are the original's, just to name a few parts.

This engine runs very quiet, no pistion slap or lifters ticking. I am now in full belief I got my moneys worth out of the car.

========= Harryface =========

1991 Pontiac Bonneville LE 3800 V6 ( C ), Black/Slate Grey _~_~_~280,385 miles_~_~_

~_~_~_~_U.S.A._~_~_~_~_~_

~~~The Former Fleet ~~~

89 Cavalier Z 24 convertible 78 Holiday 88 coupe 68 LeSabre convertible 73 Impala sedan

Remind me what code 41 is on your car? I don't have my books on that at home. Charles

Harry wrote (of the '91 Bonneville):

You better keep driving it until you make the last payment.

---Bob Gross---

Charles,

Code 41 is the cam shaft sensor circuit.

========= Harryface =========

1991 Pontiac Bonneville LE 3800 V6 ( C ), Black/Slate Grey _~_~_~280,596 miles_~_~_

~_~_~_~_U.S.A._~_~_~_~_~_

~~~The Former Fleet ~~~

89 Cavalier Z 24 convertible 78 Holiday 88 coupe 68 LeSabre convertible 73 Impala sedan

I would suggest you check the contacts in the connector. Look for any sign they have ever shorted, clean them. Check the wires. Look for any problems in the insulation, especially any area's that are brittle, pulled back, show signs of arcing, or wear. A crack in a wire can cause problems. Charles

My guess is a dying ignition circuit board if everything else checks out(the module inder the coil packs - looks like a 1/4 inch thick piece of plastic, but has surface-mount components inside it). If the silly board isn't processing the signal correctly, it can generate error codes as if the signal isn't coming at all from the sensors.

IIRC, there's also a camshaft and timing sensor(two) - so the one you checked my have been the good one.

The dealer should be able to check this in an hour or less as they'll have the boards and packs to swap out to test it.

Wait your adivsing someone to take a 13 year old car to the dealer? Are you a moron? First of all dealerships techs will have cleared out all specialized tools for those cars years ago. Second of all they will have sold off their books on them. Third why get stroked for $80 per hour? Charles

MY dealer has all the parts, tools, testers, and books. Took them two hours to diagnose my car's electrical system when two mechanics and two weeks couldn't. YMMV, of course.

Took me 5 hours to find out why a 93 Grand Am Quad 4 would not get injector pulse not ignition. After the customer outlayed $500 having it diagnosed by someplace with a Engine Diagnostic center, having a new fuel pump put in, and used fuel injectors, as well as a used ECM.

The problems: cracked plastic around the crank sensor, weak magnet, pinched wire that was shorting on starter bolt. Bad connector at DIS module.

It took 2 hours to charge the battery enough to test the vehical.

Parts cost: $60, labor: $250 diagnostic when other people have tinkered with it. $25 to replace connecctor for DIS, $10 to replace wires for Crank Sensor. $60 to change crank sensor.

If he would have brought me the car first, the diagnostic would have been $50. I hate working after other people. Since you have to inspect everything they touched. Charles

I guess it's all about the mechanic, then. The GM garage spent half a day looking and poking at the thing, mainly because the other two mechanics had messed everything up in order to get it to run at all rather than fixing it. Then they charged me the flat diagnosis fee for the 30 minutes it took to identify three seperate problems that were causing the conflict.

their time - better part of a day, off and on. $150 for the whole mess(and the car was a mess after those monkeys had tired "fixing" it.)