96 riviera sc problems. NEED HELP!!!!!

a few days ago i was driving my car around. runnin good, everything goin fine. i was doing about 55 and started to go up a slight hill and gave it a lil more gas. it started shaking pretty badly, once it shifted down a gear the shaking stopped but if i were to try floorin it, it would still shake a lil and loose power but nothing near as bad when im doin 55 crusing at low rpms. it done this for a lil then the engine light started blinking and my traction off light came on. took it home asap. it is missing horribly. doesnt sound good at all. any tips or suggestions? and could the egr valve be causing this?

Have the car scanned. Sounds like misfire. The trouble code will tell you which cylinders are misfiring. #1 cause is plugs and wires. Stick with the OEM stuff, it's hard to beat. Autozone will scan your car for free.

In addition, take the time to ask the GM dealer nearest you for a schematic of all the grounds on the car. They should be able to print this out for you. Make sure all are clean and making good contact.

Agree with Larry above - this sounds like a classic case of misfire, usually due to bad plug wires. If you replace the plug wires, spend the few extra bucks to get AC Delco or a high end wire. Do NOT get cheap plug wires for this car.

thanks for the tips. i have already replaced the spark plugs. and a friend of mine hooked a computer up to car and reset it. it quit doin it for about 50 miles then started again. and i also found a small leak in the intake gasket. l need to find a camera to post some pics. my dad bought it for 500. it sat for two years beforehand, had replace fuel pump and battery. two tires need to be replaced as well. im looking forward to getting my licence and a job. i plan on fixin her up.

so me and dad drove it to autozone. they scanned it told me cylinder 2 is mis firing. changed plug and wire. no luck so im goin to give a friend a call and have him bring over the computer that will tell me whats causing it to miss fire. hopefully he can do this by tomorrow. i will keep yal informed on whats happenin

Personally I would replace all the plugs and wires, and with nothing you can buy at Autozone. But you should also make sure all your injectors are firing, after sitting that long I wouldn't be surprised if one of them (or more) doesn't work right, that could easily be the cause of a misfire.

You can try removing the fuel rail and swapping the injector locations, and see if the misfire moves to another cylinder. Swap #2 and #4 injectors, for example, and see if the misfire code changes to #4.

Another way to find leaky or non-working injectors, with a scan tool your STFT and LTFT numbers will tell if the car is running overall rich or lean. You should get the car warmed up, log the numbers at idle, then unplug the wires from one injector, wait a minute for it to settle out, record STFT/LTFT, then reconnect the injector and move to the next cylinder. Find the one that makes the least/most difference and you have likely found either the leaking or plugged injector.

i replaced all spark plugs when i first got the car. but i will replace the wires to when i find out whats causing it to happen, should be tomorrow.

When you do the wires, remove each spark plug and check for cracks in the insulation. It's easy to do when installing the rear plugs, lean a little to hard and 'crack'... I did it a few times, and it runs pretty much just like you describe above.

It's worth pulling all the plugs out and giving them a close visual inspections (is one very discolored? any cracks at all?) and maybe just replace for good measure. Cheap insurance.

A bad wire can also cause the plug to short out, and there will be a carbon track on the white porcelain of the plug. Once that happens, the plug will continue to short when the demand is high.

LARRY70GS wrote:

A bad wire can also cause the plug to short out, and there will be a carbon track on the white porcelain of the plug. Once that happens, the plug will continue to short when the demand is high.

I had the same exact problem this weekend and this was the culprit. 2 of them were cracked right down the middle. Took looking at it at night and I could see the porcelain lighting up.

ok so he brung the computer out and it had a trans code on it and a missfire. he listen to it runnin and he says from the noise it making the lifter is broken or fallin apart. so we will see when i start taking it apart to fix the intake gasket. and we have another car with a 3800 in it with about 80 thousand miles. and mine has 121000. should i swap? or fix the one thats in it?

crstump wrote:

ok so he brung the computer out and it had a trans code on it and a missfire. he listen to it runnin and he says from the noise it making the lifter is broken or fallin apart. so we will see when i start taking it apart to fix the intake gasket. and we have another car with a 3800 in it with about 80 thousand miles. and mine has 121000. should i swap? or fix the one thats in it?

I think it's not worth the trouble of switching engines at this point. The lower half are well known to be very reliable. Fix whatever valvetrain issues you find, replace the plastic intake gaskets with aluminum, replace the plastic elbow in the lower intake, and you shouldn't have any more mechanical problems. I think that's less work than swapping motors to another that will probably need IT's intake gaskets replaced soon anyway...

That happened to me and it ended up being the coil...coil maybe?

i will see when i fix intake gasket. and i told dad that engine swap would be to much trouble and i just wanted to prove him wrong by askin yal. we gotta get some space cleared out in the garage before i start on it.