1994 corvette start

[Richard Cooper]

Hi, We are having problems with a 1994 Corvette we are working on. We flushed the cooling system and now vehicle will not start. We started by draining the coolant and refilling with water and flush. We then let the car run for 30 minutes watching temperature so as to not overheat. We then let cool and drained and filled with clean water. We started car for a few minutes and drained, at this time we replaced thermostat and filled cooling system with coolant and rinsed off front of engine were we had some overflow from thermostat replacement. We then started the car and it ran fine but then started to run rough then stall, upon restart while turning over it would initially turn over and try to start but then sound as if the timing was advanced. We are sure we didnt over heat and was wondering if maybe we had got some water on the air sensor plug prior to connecting if this would cause this problem or what thoughts you might have. Thanks

[Terry M.]

[Guest]

Re: 1994 corvette start

I agree with Terry that it is most likely water in the Opti-Spark. I had a neighbor a few years ago who washed his 94 engine. It too ran rough after getting the Opti-Spark wet. He dried the engine by blowing a fan over it for a few hours, and it then ran fine. There are no guarantees that it will work for you, but it only costs a little electicity to give it a try.

It is a real pain to change the Opti-Spark. If you do have to change it, you should consider changing the spark plug wires and water pump if they have not been changed in a long time. Especially the water pump. Your water pump will leak at some point and then it gets the Opti-Spark wet. You are lucky to get 50K to 60K miles out of one. I have a 95 with 130K on it and have replaced the water pump twice and Opti-Spark once.

[Joe L.]

Re: 1994 corvette start

Terry and Richard-----

1994 Corvettes use the non vacuum aspirated Opti-Spark distributor. This is the more expensive one of the two. It's GM #10457702 and it carries a current GM list of $674.14. Dal's price on this one will likely be closer to 400 bucks.

The 95-96 vacuum aspirated unit is GM #1104032. This unit carries a current GM list price of $502.94. The 2 are not interchangeable, although the later design unit can be used if other parts are also changed. While there may or may not be some durability advantage with the later unit, the cost of the parts to make the conversion exceeds the difference in price between the 2 distributors. The first design (actually, the second design since the very first design is obsolete and not serviced) can also be converted to vacuum-aspirated configuration with the expenditure od some effort.