91 ZR-1 Cutting Out Under Load

[GregCrowe]

Originally Posted by LT5-Lee

Howdy, I was just curious if anything else has been learned since the last postings?

I am very curious as I think I have basically a '91 with "carbon copy" symptoms of your problems also!

I just started checking everything before a plenum pull, but I already have RC injectors and a fuel filter replaced. I guess I was hoping it was bad gas, but I know better since it ran good without any fill up in between.

Anyway, just hoping it is not a ECM.

Lee

Lee, I'm so disgusted with this car. I can't seem to be able to fix it. It's been almost 3 years since my first post and the car has just sat in the garage. I've only driven it maybe 10 miles. At this point I'm totally worn out on it and tired of throwing money at it. The only thing I can figure now that might be a possibility is:

1. ECM
2. Ignition Control Module
3. Coils

I'm sick of pulling the plenum. I'd love to try another ECM and see if that fixes it. Someone out here once offered to let me try their spare but never replied back. My ZR1 just sits in the garage. I don't drive it, can't sell it like this........ totally disgusted with it. It's a giant paperweight taking up space in my garage.

[Zr1 Destroyer]

Try the coils first since they are cheap and easy to replace!

[jonszr1]

you arent that far from corey henderson ,new braunfels texas 210 867 6286 .why not tow it to him and have him fix it for you he is one of the best on these cars. couldnt hurt .as its got under your skin .

[lbszr]

Mine had similar issures with two coils bad and the restistance was way out on two of them and the missing was intermittent. Autozones coils lasted one year, slight intermittent miss came back, resistance checked good on all four but changing them to Standard coils the miss has been gone for a few years so far. And I found brand new not all coils checked the same. Parts stores probably didn't like see me showing up with a multimeter. Some were twice the resistance.

Originally Posted by GregCrowe

Lee, I'm so disgusted with this car. I can't seem to be able to fix it. It's been almost 3 years since my first post and the car has just sat in the garage. I've only driven it maybe 10 miles. At this point I'm totally worn out on it and tired of throwing money at it. The only thing I can figure now that might be a possibility is:

1. ECM
2. Ignition Control Module
3. Coils

I'm sick of pulling the plenum. I'd love to try another ECM and see if that fixes it. Someone out here once offered to let me try their spare but never replied back. My ZR1 just sits in the garage. I don't drive it, can't sell it like this........ totally disgusted with it. It's a giant paperweight taking up space in my garage.

Greg, send me your address and I'll send you a ECM to test. The DIS modules rarely go bad, and I'm still suggesting coils.

[XfireZ51]

Originally Posted by GregCrowe

Lee, I'm so disgusted with this car. I can't seem to be able to fix it. It's been almost 3 years since my first post and the car has just sat in the garage. I've only driven it maybe 10 miles. At this point I'm totally worn out on it and tired of throwing money at it. The only thing I can figure now that might be a possibility is:

1. ECM
2. Ignition Control Module
3. Coils

I'm sick of pulling the plenum. I'd love to try another ECM and see if that fixes it. Someone out here once offered to let me try their spare but never replied back. My ZR1 just sits in the garage. I don't drive it, can't sell it like this........ totally disgusted with it. It's a giant paperweight taking up space in my garage.

Greg,

Boy this has been going on too long. I sympathize with your frustration. I strongly doubt its either the ECM or the module.
I have a set of stock coils that worked fine before I replaced them with
MSDs. Let me know if you'd like to try them out. Its a shame to see a perfectly good ZR go to waste.

[XfireZ51]

Originally Posted by GregCrowe

Well, finally after 2 years I have now ordered the Accel fuel injectors and a new fuel pressure regulator. This morning I have a new problem. I am now informed that the 90-92 Corvette ZR1 fuel pressure regulator is a discontinued item. I'm still reading 32 psi with a new fuel filter. Any suggestions on where to get a FPR ? An adjustable one would be ideal.

Did you ever pull the fuel pumps?
I didn't catch how many miles were on the car but the 30psi at idle isn't right. Has that been rectified? If not and you've changed the fuel filter, I would look at the sock filter on both pumps. They may be plugged to the point that they'll look like they are being sucked in by pumps. In that case I would replace the pumps since they probably been overheating trying to get fuel out. I had problem with my fuel pump filter causing the secondaries to shut down due to lean O2.

[ZR1Vette]

I looked thru the FSM and found these...just in case you need more options to consider>>

[XfireZ51]

Fuel system is the first thing on both these lists. The stumbling that happens when the accelerator is moved can be due to the lack of or insufficient pump shot. Without sufficient fuel pressure there isn't enough fuel and the mixture goes lean causing the momentary stumble and lack of power.

[GregCrowe]

Originally Posted by lbszr

Mine had similar issures with two coils bad and the restistance was way out on two of them and the missing was intermittent. Autozones coils lasted one year, slight intermittent miss came back, resistance checked good on all four but changing them to Standard coils the miss has been gone for a few years so far. And I found brand new not all coils checked the same. Parts stores probably didn't like see me showing up with a multimeter. Some were twice the resistance.

Did your car have to heat synch before you started having miss/coil problems? That's the crazy part about my car. Also, what are you calling "Standard" coils. Where do you find good ones for a decent price?