Optispark install gone wrong
 

My friend and I just installed a new opti and waterpump on his 94 Z28. But now his car wont start, it will crank really rough and if he keeps doing it we can hear a hissing noise and then all this smoke starts coming out of his intake by the MAF. We have checked and double checked all of the plug wires, and we made sure we hooked everything back up correctly. Is there anything we're missing? It's really weird that his car wont start now. As always all suggestions are appreciated.

Are you sure yo got the opti to set flush with the block and the cam dowel in the slot on the opti?

wow, that is exactly what happened to me on thurday morning. i suggest you might wanna double check if you put the opti correctly. it has to stick in to the firewall. do not leave any gap at all. i also have a 94, me and my buddy just finished doing all that last night. my car did not want to start at first, it turned out to be a bad opti. i bought the opti off someone from the board, and he sold me a bad opti. he wasted my time and my energy. so if you bought your opti used, you might wanna check that. was your old opti dead?? you might wanna try putting the old one back on, just to see if it fires up. good luck man. i know how it feels. i've been there less than 24 hours ago :( as soon as i put my old opti back on. everything starts fine. and my car sound loud as hell. :D because no CAT. my Y-pipe was open untill now....:D

No, its a brand new opti, he bought it from Jason Cromer. I guess we'll check if it is flush with the block. Hope that it fixes it.

When installing the opti, you need to make sure you have the cam dowel lined up with the correct slot on the opti. When you slide the it in the cam you will usually have to wiggle it a little bit or maybe slightly move the crank hub to get it to drop in all the way and have it sit flush with the block. You do not want to tighten down the bolts to draw it onto the block.
Other than plug wires being in the wrong spots thats all I can think of. Maybe check to see if you have all the connectors plugged back in.

Well since it's a 94 there is no 'dowel pin' for the opti drive.. That's for 95 and later..
It's a splined shaft with one tooth that's 'solid' that indexes it..
And it can rather easily be forced on the wrong way..
Make sure that one tooth is properly indexed, both in the opti and into the 'shaft drive hole' [timing cover side]..
Sounds like it could be off some..
:cool:

Dude, I had the same issue earlier this year. Not that bad, but it started hard, ran lean quick up the rpm band, and smoked black like mad after I installed the 42 lb injectors. The timing was off due to the opti being installed two teeth off. The problem in mine was, even though the shaft coming out of the block was keyed, as was the gear in the opti, it would install when not lined up properly. Here's how I checked it:

Pull #1 plug, and get the motor rolled over to "top dead center". I put a que-tip in #1 hole, pulled the coil wire, and had someone bump the motor over until I felt the piston bump the que-tip. I then used soapstone (chalk will work too) and made a timing mark on the balancer and matched it up with one on the block deck. Reinstall the plug and coil wire, start it up and hit it with a timing light. A setback timing light is the ticket, as you can dial it up and see how many degrees it is off. My pcm sets my timing at 29 degrees at idle. My timing light brought the mark back to TDC at 60 degrees, timing was 31 degrees off. If you are out much more than that, the motor probably wont even turn over right. Here's what I did:

Get the motor back to "Top Dead Center, TDC", and get the opti back off. At TDC, the shaft exiting the timing cover should have the keyway right at the top. Check the opti and see if the keyway in the gear is in the same place. You can use that little block in the back of the opti as a reference, as it is straight up when it slides into the timing cover. If its off, roll the gear the shortest distance around back to the top, referencing that little block in the back of the opti. It should now be lined up correctly when you slide the opti back on the shaft. Mine even felt like it slid on allot easier than it did the first time. Button it back up and fire it up. I noticed a difference immediately. Hope this helps.

Larry

Always check the basics before anything: Are plug wires in the correct firing order?

Oops, didn`t pay enough attention. What Mtrhds94z sounds good though:D