The Oldsmobile Connection

Oldsmowbill · Joined: 10 Dec 2004 Posts: 22 Location: Campbellsville, Ky

Engine: 3.8
Miles: 130K

Symptom:

This has only recently been occuring in the last couple of days and started happing all of the sudden.

It seems like when I'm taking off from stop, the whole car vibrates and if I let off the gas a little, it smooths out. If I step on the gas real hard and fast and take it all the way to the floor, there will be a "pop". One time, it died when I did this.

Occurances:

The first time it happened, I noticed this and drove it back home and jumped in my backup car. Later on that night, I got back in the Olds and noticed that it did this only for a few seconds and never did it anymore.

Couple of days later, it did this again but I drove about 20 miles and it smoothed out.

So, does anyone have any recommendations on a good troubleshooting starting point?

Thanks!!

OldsGuy · Joined: 16 Feb 2004 Posts: 269 Location: Lees Summit MO

Sounds like ignition timing but with computer controlled timing events I don't know. Maybe the distributor hold-down bolt is loose and your initial timing has slipped. If there is a way to pull a code and see what you come up with I would try that too. Maybe turbo can help you he is more experienced with the newer engines. Good luck man,

Brando · Joined: 06 Jun 2003 Posts: 3069 Location: Michigan, USA

First thing is to get it scanned and see if any codes pop up...

TOC Admin
Brando

speedy266 · Joined: 25 Jun 2003 Posts: 347 Location: Ontario, Canada

MAF sensor?
which 3.8L engine do u have? 1991 Ciera's came with 3.8L's?? i thought the last year of 3.8L's in cieras was 1988.

Brando · Joined: 06 Jun 2003 Posts: 3069 Location: Michigan, USA

speedy266 wrote: MAF sensor?
which 3.8L engine do u have? 1991 Ciera's came with 3.8L's?? i thought the last year of 3.8L's in cieras was 1988.

Good call...probably the 3.3L, unless he did a swap...

TOC Admin
Brando

88delta88 · Joined: 09 Jun 2003 Posts: 2409 Location: Canada

I had the same problem... My car backfired at times, and it was caused by a damaged plug-wire boot and it was arcing straight over to the next spark plug wire, and firing that cylinder at the wrong time.

The boot was damaged at the ignition block, and would just jump to the next wire. I only figured this out becuase I actually saw a blue spark jump by accident, and said AHA!

Just a suggestion

Turbocharged400sbc · Joined: 18 Aug 2004 Posts: 318

ah here we go! 88delta88 has it on the money look at your ignition cables (spark plug wires) closely, 130k miles, if it was last tuned up at 70k (plugs/wires/pcv/etc) you may be needin it soon! the bast i can surmize is it might have been humid the days you had the problem (rainy lately? etc) and they atarted arcing once they start arcing the carbon tracks let it ark at the slightest bit of engine loading.
take a spray bottle with some soapy water in it and spray down the wires at the coilpack to the plugs and with the lights out and it dark while the engine is running and you will see a nice little lightning show
(dare ya to stick your tounge on it! LOL-better than coffe in the mornin!)
where the voltage leak is (usually near the coilpack or the plug boots)
then replace your spark plug wires with some quality ones (cheapo's are for when you SELL the car lol) (ACDelco, Belden etc) and get new plugs and put them in also (with correct gap) (helps to put the silicon Dielectric grease inside the ends of the wire boots-makes removing them easier next time-this is sometimes included with the wires)
hope i could help ya some
BTW not much else can cause the problem your experiencing (unless a squirel/rodent chewed through some harness wires LOL)

Oldsmowbill · Joined: 10 Dec 2004 Posts: 22 Location: Campbellsville, Ky

You guys are right. The engine is a 3.3L. Sorry.

Oldsmowbill · Joined: 10 Dec 2004 Posts: 22 Location: Campbellsville, Ky

Quote: the bast i can surmize is it might have been humid the days you had the problem (rainy lately? etc) and they atarted arcing once they start arcing the carbon tracks let it ark at the slightest bit of engine loading.

Yes. As a matter of fact, it's been raining for the last two weeks and this has been happening during this time.

The worst I've seen it run was the other night when it was really damp and foggy.

Turbocharged400sbc · Joined: 18 Aug 2004 Posts: 318

replaced your plugs/wires yet?

Oldsmowbill · Joined: 10 Dec 2004 Posts: 22 Location: Campbellsville, Ky

Not yet.

I will post results as soon as I do.

Thanks

Brando · Joined: 06 Jun 2003 Posts: 3069 Location: Michigan, USA

Taking a while to replace those plugs and wires! :?

TOC Admin
Brando :)

Oldsmowbill · Joined: 10 Dec 2004 Posts: 22 Location: Campbellsville, Ky

Update:

I just now replaced those wires. (01-31-05)

It did indeed stop the miss and backfire.

I drove it about 100 miles the other night in fog and rain with the new wires and it didn't miss a lick.

And just a note: Those were Autolite wires that failed. I did replace them with another set of Autolite's.

Oldsmowbill · Joined: 10 Dec 2004 Posts: 22 Location: Campbellsville, Ky

Oh and thank you very much guys. While time wasn't an issue on this, it saved me a buttload of troubleshooting in which I hate.

The internet makes life so much easier doesn't it?

Thanks again!!!