ok i have posted a couple things on here and have had great help. so i just got done installing a very low mileage engine out of a 95 into my 93z28. the actual miles being seventy five hundred original. i put it all together and i have no spark at all. now i know the opti's go bad on these but i wouldnt think with that low of miles on it that the problem would be opti. but ya never know. i swapped a good coil and module off my buddys trans am to see if maybe that was it no luck there. we took the coil wire off the opti side and left it in the coil and theres no spark there either. im kinda getting discouraged i did all this work and no luck. i am not an electrical whizz by far. but all the wires and grounds are hooked up. now i will say the i used my 93 wire harness section the runs off the intake to the opti. beings i have a 95 vented opti would that harness section matter? i mean it plugged into the 95 opti. any help would be greatfull

 

Check both plugs on the opti to car harness to make sure the sequence is the same. There are small numbers, or letters on the end near the wires. Either 1-2-3-4, or A-B-C-D. I put a new 92-94 style opti on my 92 Vette. My car had a one year only style plug, so I needed to replace the plastic metripack plug end on the car harness to match the new style plug on the opti, but it worked just fine. If one plug has numbers and the other letters, then 1+A, 2+B, 3+C, and 4+D.

 

95 opti will work with a 93 setup. how long has the motor been setting and in what enviroment? opti can rust on the inside, did you take the cap off and look to see what shape it is in? are you getting power to the pink wire at the coil when the key is on?
http://shbox.com/1/4th_gen_tech2.html#opti_test
heres more

 

Craby, that is out of your 93 book, right? 95 is the new style vented opti. I don't spose you have an illustration of a 95 opti wiring to make sure the wire order is the same?

 

i have a 95 style vented opti in my 93 and it works fine. had to get the 95 harness for the opti but it plugged right in the main harness. seems to run good and no codes.

 

Mattzilla said he ran his 93 harness to the 95 opti. Why did you have to get a 95 harness, were they different?

 

the plugin to the opti is longer on the vented one.

 

Yeah, I do remember that, now that you mention it. So how did he get his shorty plug to work in the opti...or maybe he only thinks it's plugged in?

 

never thought of that. i was assuming the harness come with the motor. wonder if matt is still around. lol. seems like we are talking to each other and hes gone. lol.

 

I read that as he used his entire old short plug harness. That ain't gonna work...oh, mattzilla!!!
So craby, how's the weather up by you?