ZR-1 Net Registry Forums - View Single Post - 1990 ZR-1 Hesitation when full Power

dcarroll95 · 01-10-2019

Ditch the secondaries - they will fail one way or another and if you ditch them no more secondary issues. You'll need a chip from Marc Haibeck to reprogram the car to split injector duty, but then you get a known tune.

While you're doing that test the injectors. Test the coils by measuring resistance between the two plug wires that share a coil. I had one at 30k and the other 3 were 18-20k. The 30k is bad.

Check out the "secondary remove guide" post that I recently commented on. It has instructions that I followed and wasn't too bad. Maybe you'll get lucky like me and find out the heads and plenum were already ported by a previous owner.

01-10-2019	#5
dcarroll95 Join Date: Dec 2018 Location: ALLEN Posts: 10	Re: 1990 ZR-1 Hesitation when full Power Ditch the secondaries - they will fail one way or another and if you ditch them no more secondary issues. You'll need a chip from Marc Haibeck to reprogram the car to split injector duty, but then you get a known tune. While you're doing that test the injectors. Test the coils by measuring resistance between the two plug wires that share a coil. I had one at 30k and the other 3 were 18-20k. The 30k is bad. Check out the "secondary remove guide" post that I recently commented on. It has instructions that I followed and wasn't too bad. Maybe you'll get lucky like me and find out the heads and plenum were already ported by a previous owner.