On my 94 buick roadmaster (LT1) I've been having what appear to be fuel related issues lately. It will occaisionally sputter and sometimes hesitate. If feels like there is water in the fuel. It usually happens right around 50 mph and never happens when starting out. I've changed the fuel filter, dried the gas and it still happens once in a while. The other odd thing that happens is that occaisionally the engine will spin a few times before firing (maybe 2-3 seconds). In the past, it would always start immediately. This has coincided with the sputtering. The only trouble code I can get out of the climate control center is in the 02 diagnostics mode, where the number 126 alternates with 110. I believe the 02 mode is for HVAC diagnostics, so Im not sure how this could be related to engine performance. Any ideas? Thanks in advance.
Up here closer to the Suwannee River we often get bad gas. Once it was so bad I had to drain the tank and the mower. But the gas stations will say it wasn't their gas. Good luck.
Is it wet out when this occurs? If so the seal on the OptiSpark Unit may be Bad. I hate to tell anyone that as they are a PITA to replace, and not cheap. If the water pump ever was replaced on your car, the opti was likely exposed to coolant. And that can cause any number of issues. If you are not familure with them just google GM optispark and you will learn more than you ever want to know about them. After working on several 93-97 Firebirds with LT-1's I decided to Buy a 97 3.8 convertible for myself.
Its pretty much wet here all the time. Any definitive way to know for sure it's the opti and not fuel-related ? Drier weather is just around the corner. Should I wait and see if it clears up on its own, or is it just going to keep getting worse?
This is the T/S procedure I used to use. This Link has a good sumation of it. http://www.thecorvettemechanic.com/...OPTISPARK-DIAGNOSTICS-or-is-it-something-else I know that decent rebuilt units can run over $400 just for the parts. It is the reason I will not own a LT1 powered car. The rest of the engine is fine, good Power and good MPG. And you do have other options now, I hear you can even put in a normal distributor if you have the room. I 1st ran into this issue on a good friends 97 Ram Air T/A, great car, but every time he washed it water would get into the Optispark unit from the hood scoops. He would have to wait about 1 hour to start it, and it would run rough until the engine got to operating temp and burned the water out of the unit. He being cheaper than I am never fixed it, and traded the car the nest spring for a 04 Vett.
It's been dry here for a couple of weeks and everything is back to normal. Must be somehow related to electrical.
