1989 Bonneville sudden problem

Folks,

I've got a 1989 Bonneville SE that has been running just fine until today. This afternoon I took off on a short trip to pick up my son from school. We're talking about a 10-15 minute residential drive. Parked the car on the road and waited about 10-15 mins for my son. Went back to the car and it started right up. Then it died. It started right up again, then died. Tremendous smell of gasoline came in through vents. Popped the hood. Didn't see anything obvious. The key was in the "run" position and I could hear what sounded like a crackling or sizzling sound. No smoke though. Checked under the car. Nothing obvious. Started the car again with some trouble and could keep it going if I kept my foot on the gas pedal. Limped it home. After about an hour I went back and started the car with trouble and it died as soon as I let up on the gas. Again, left the key in "run" position and again heard the sizzling sound right around the fuel line or injectors. After about 5 minutes the sizzling went away. Started the car with some difficulty, but after a few moments the RPMs went up and the car smoothed out. Took my foot off the gas and it seemed all was just fine. No shake, no stall. No problem at all. Now some 4-5 hours later I just checked it again. Started right up but idled very rough and tremendous smell of gasoline again.

Any ideas? Car has 150K miles +.

Paul Nixon

Reply to
khobar
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If your hearing a sizzling sound that almost sounds like gas being boiled off the pockets of the intake manifold that the gas is pudling up in. Check for a leaking injector. I had this happen on my Z -24 SSSSSSssssssssss. Could cause a fire!

Check the schrader valve in the fuel line for leaks, It looks like a tire valve stem with a big cap on it. You can see it sticking up through the plastic engine cover.

Check for proper fuel pressure. Could be a bad Fuel Pump or Fuel Pressure Regulator, which is located on the front fuel rail to to the right.

The gas filter should be changed every 30,000 miles.

Good Luck.

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

1991 Pontiac Bonneville LE ~_~_~267,300 miles_~_~_
Reply to
Harry Face

Also, as a quick check, pull the vacuum line from the fuel pressure regulator. If gas comes out, you've found a faulty regulator. GW

Harry Face wrote:

Reply to
Geoff Welsh

Check or have dealer test your MAP sensor locate on throttle body.

Reply to
MN

Thanks for the replys folks.

I did a quick check this morning. Car started up immediately but ran very rough. Did not have to depress the gas pedal to keep it going. I moved the car from the side of the house to in front of the garage. Rough idle but no stall.

With car running:

I checked for "wetness" and any signs of gas leaking on top of the engine. No signs of leakage.

I tapped the coil packs and fuel bar. Made no difference.

I did hear that "sizzling" sound. Could be faulty injector? Could be faulty module?

Could it possibly be caused by a faulty *voltage* regulator? I ask because the A/C compressor seized in February and the battery cracked. I replaced the compressor and battery but the car has had some electrical problem ever since most apparent when the aux fan kicks in. I discovered the relay for either the main or aux fan makes the same or very similar "sizzle" sound as I'm hearing from the very top of the engine.

I also noted what looked like steam (white) puffing out the exhaust. Since it was early morning I don't know if it simply was steam or what.

With the engine off:

I checked the schrader valve. It was functioning just fine.

I tried to detach the vaccuum line but failed. Will try again.

Thanks again,

Paul

Reply to
khobar

Okay folks, here's an update.

I checked each spark plug. All shows signs of carbon, but the one in the middle at the front of the engine (sorry, I don't know the cyl #) was literally dripping with gasoline. Obviously not firing.

I changed the spark plug and plug wire. No difference.

Okay, now this is starting to sound like I have a bad injector. Perhaps one that is kinda stuck open or something??? Or this indicates some other problem.

Does this provide the needed info?

Thanks again,

Paul Nixon

Reply to
khobar

Would appear that a faulty ECM was the problem. I replaced the computer and the car is back to "normal". Thanks for all the input. Much appreciated.

Paul Nixon

Reply to
khobar

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