was driving home last nite, was noticing a slight "buck" for a quick second while accellerating. decided to stop and try a "full power" acceleration to see what would happen. as i came to a stop the car died.

tried to start it and it would barely start, would fire, run then die. had to give it a ton of gas to get it to stay running...but it still stayed rough. was nursing it down the road to get to a pull off, and i was able to get it running like normal...took a mile or so or revving, bucking and nearly dying the whole way.

seemed fine, drove it the last 10 miles home without incident, even stopped just before my apartment to see if it would die...no problems.

get in it this morning and the same thing happens as i'm pulling out of my driveway. i notice the SES light is on (in a new place on dash from my 96...could have been on last nite). i had to nurse it the 1mile to work and it died 2 times... i had to slip the clutch and rev it alot to get it into the parking lot.

any ideas of what it could be. i'm planning to get it scanned if i can get it to the shop. but what could cause a random "act up" like that?

 

Tons of things could have happened, you could have broken a pushrod or a spring, or some other type of valvetrain failure. Your crank position sensor or cam sensors could be going haywire, you could have a problem with one or more ignition coils, or you could have even blown out a spark plug (don't laugh, it has happened before).

First thing I'd do is reset the PCM. You'd be surprised at how many problems that could fix.

Then get the codes read. If it is a sensor, that will set a code, see if that tells you anything.

If not, then check all your spark plugs and make sure theyre all still there and not loose or gummed up.

If they look okay, then I'd pull the valve covers off and inspect all the pushrods and all the springs. If everything looks okay there, then I'm out of ideas, you will more than likely want a mechanic to tear the engine apart to figure out what else it is.

 

thanks for the info.

i already pulled the battery cable and cleared the computer. didn't solve anything.

one thing...last nite i don't remember seeing the SES light on. granted like i said it's ina different spot so i may have just missed it...but i know it WAS on this morning.

i've had it running (barely) a few times this morning after reseting the pcm. even took it for a short drive (stalled 5 times). and sofar the SES hasn't come back.

it seems like it is running really rich, like i can smell gas when runnning....although this could be from the revving to keep it running. soon as i lift off the gas, it drops rigth down to 2-300rpm and dies.

is it possible that my maf has gone haywire? what happens if i unplug the maf? seems i remember something about "limp home" mode from my old 96z...is it the same on the ls1?

i'll be checking plugs later today

 

figured it out...

i tried a trick i knew from the lt1's...unplug the MAF sensor and see if it runs...

well it did..

so i swapped out the ZO6 maf for the original with some GMS maf ends that i had from my old car...and she runs like a champ now.

damnit!! pisses me off that the zo6 maf died after only 6 months...grrr...

 

baaaaaaaaaaaaaaaaaaaaaaadddddddddddddd gas.
Try changing your fuel filter and add some drygas to remove water.

 

thought about gas, mostly that someone put something in the gas...since it ran fine for the first 1/4 tank..

but when i switched back to the stock MAF sensor (from my zo6) it ran like a champ...

so i guess my aftermarket maf died on me

 

I bet it starts again, If it still does it im betting its the o2 sensors and your cars a 99 so its about that time, my car did the exact same thing, id put money on it. it took me forever to find the problem. very expensive it cast me $250 for a set. I only had the pre-cats because I had sims for the after cats because I done run cat but the were only $100, hope this helps