: 95 Harness --> 93 Block/sensors?



botboy
03-03-04, 04:12 PM
Because a friend is getting a whole new powertrain module for his '95 STS, I'm going to have the opportunity to buy an engine harness for a '95 OBDII northstar for pennies on the dollar. I have a '93 Block I'm currently rebuilding, and am going to put in one of my "fun" vehicles with some modifications. Eventually I want to chip it for more performance, which I cannot do with a '95 (OBDII) harness but can do with a '93 harness/ECM. Are there any differences between the '95 and '93 sensors on the engine?

Can I just connect everything without changing anything?

I'm guessing here...but I can't just drop in a '93 vin Y ECM on the '95 harness, right?

BeelzeBob
03-03-04, 04:56 PM
Because a friend is getting a whole new powertrain module for his '95 STS, I'm going to have the opportunity to buy an engine harness for a '95 OBDII northstar for pennies on the dollar. I have a '93 Block I'm currently rebuilding, and am going to put in one of my "fun" vehicles with some modifications. Eventually I want to chip it for more performance, which I cannot do with a '95 (OBDII) harness but can do with a '93 harness/ECM. Are there any differences between the '95 and '93 sensors on the engine?

Can I just connect everything without changing anything?

I'm guessing here...but I can't just drop in a '93 vin Y ECM on the '95 harness, right?
Well...the 93/94 engines are virtually identical and the 95 is very very similar except that the 95 has an all plastic intake manifold where the 93/94 had the magnesium die-cast intake manifold with the lid and the plastic tubes inside.... The 93/94 had part of the wiring harness inside the intake manifold with a large connector at the end of the manifold housing to connect to the rest of the engine harness. Fundamentally, there is no difference in the 93/94 system and the 95 although there are hardware differences and location of sensor differences. Basically most everything would plug in but you might end up extending some of the wires. If you have a 95 engine harness it should plug into a 93/94/95 PCM as the PCM was the same as I recall. The 95 harness would have to be modified at the intake if you are using a 93/94 intake. If you have the intake then there should be a harness inside of it and all you need to do is cut the 95 harness to mate up to the connector at the end of the manifold. If you don't have a manifold for the 93 "block" as you say then you need to find a 93/94 intake as that is the only one that will bolt up to the cylinder heads for a 93/94. The 95 manifold had more bolts and a different set of holes for the EGR and PCV routing....