The ECM has two drivers and fires each bank of the engine (4 injectors/bank) independantly. In effect, the driver supplies the injectors with a "ground".

 

So, has he figured anything out yet? This thread is really interesting. I don't know how the hell you guys do this stuff. I open my hood, and then close it quickly again because it's too intimidating. I did sucessfully install my CAI and am going to try the TB bypass soon. Oh, and I've worked on alot of cars all my life, just nothing like the cramped confines of my Z.

 

What became of this? Im curious to see what happened.

-B

 

Updates? Is the guy still alive?

 

You can remove the tach filter. When I did my swap the tach was jumping all over the place and would sometimes slam to zero then start jumping around again. Cut the filter out and reconnect the wires. This immediatley fixed mine.


If you're still here

 

So what happened with the hell bent lt1 vette?

 

It's been a while since I've checked this thread, I diddn't realize that I never closed the loop!

After all the diagnosis and troubleshooting, pain & misery, blood sweat & tears, here is the final outcome: The OPTI was the problem. But not in the way that ANYONE would expect.....

On the '92-'93 model year (the first year(s) for the OPTI) GM used a very small, fine-splined shaft to couple the opti to the camshaft gear. The splines on this shaft were extremely fine, and are VERY prone to incorrect "keying" into the mating parts. The method that GM used to 'Key' the shaft to the mating hole was to fillet weld between two of the splines. With a little bit of force it is EXTREMELY EASY to force the slined shaft into the camshaft gear OR THE OPTI in the incorrect position. In 1994, GM switched to a MUCH MORE BEEFY shaft, splines, and a positive keying method to apparently eliminate field issues with the previous design.

When I pulled my opti off, and checked to make sure the shaft was keyed correctly, I checked it from the SHAFT TO THE CAMSHAFT GEAR. I did not check it from the SHAFT TO THE OPTI. To do this, you have to buy a specialized REVERSE TORX DEEP SOCKET 3-4MM SET from snap-on (~75 bucks) and take the OPTI apart. Then, and only then can you check to see if the shaft is aligned properly to the OPTI.

That was the problem the entire time, the car was out of time electrically. Is was severely retarded, (in more ways than one), which explains the red hot exhaust manifolds, dying when given more gas, etc etc.....And because there's no timing marks on the balancer anymore, no way to verify timing!!!!!!!!

LESSON LEARNED: The splined shaft should literally fall out of either the OPTI or the camshaft gear when the OPTI is removed. If the splined shaft is hard to pull out of either, and the car has runnability issues, THIS SHOULD BE A BIG RED FLAG!!!!!!!

I'd like to sincerely thank all of those who helped out along the way...After replacing the splined shaft, it started up right away, and I've put over 25,000 miles on it year-to-date!!!!!

 

this was very interesting. I am happy the car runs, and hell of a job going over things.