I have a 1996 camaro standard edition with a 3.8L V6. The motor blew so i had to replace it with another engine, out of a 98 camaro. The newer engine has very low miles and the compression tests came up good. But when i turn the key, it misfires like crazy i dont think it could possibly run any rougher. We had to splice each of the oxygen sensors in order to install the motor. I thought that it might be a sensor but the check engine light doesn't flip on. I know that the spark plugs are in the right firing order and everything should be connected right. Could it be the computer has to be reset for the new motor? Can anybody help me i would greatly appreciate it. It's a very good car and i hate to have it just sitting there, rusting and being useless.

 

Just curious as to why you had to splice the O2 sensors?

 

Were the computers different? Both have/had coil packs correct?

 

I KNOW THE THROTTLE bodies are different... did you use the computer out of the 96 or 98 for thenew motor?????

 

I had to splice theO2sensors becausethe computer in there connects to the sensors with 4 pins all in a row. The sensors in the new motor conect with the same 4 wirestwo rows of two pins.The computers are different... the car hasthe original 96 computer. I don't know about the coil packs; i'll check.

 

Throttle bodies are both angled and use a cable. All 3.8 Camaros have coil packs and same firing order. I was curious about the O2 sensors, as that may be the reason for the rough running. Are you sure they were correct when you spliced them?

 

I had a friend do the splicing on the sensor wires.They lookgood and the check engine light doesn't come on... I'm not sure if that means they're ok though

 

The sensors were from your car, or came w/ the new engine?

 

They came with the new engine... I would have replaced them with the old ones, but i already mounted the engine and the sensors were kind of a pain to get to. I thought the splicing would be easier

 

All I can suggest, is to try the old sensors,since you're using the old brain. I can't think of anything that would make it run as horrible as you describe.