91 ZR-1 Cutting Out Under Load

Originally Posted by GregCrowe

Please excuse my ignorance but what is a DIS module?

What you are calling the Ignition Control Module.

[lbszr]

Originally Posted by GregCrowe

Looking at these coils on both Auto Zone and OReillys websites and it looks like the ZR-1 coils are the same generic thing as the 3 coils on a 3.8L V6 which I know are always problems. Is that right? The same coil? I can't even tell you how many of those things I've replaced on 3.8L's.

I wouldn't buy auto zone's coils, tried that. Think they are the same.

[Zr1 Destroyer]

Originally Posted by Tyler Townsley

If you want to borrow my checker let me know I have lent it out in the past.

Tyler

I might take you up on that dis checker.

[XfireZ51]

Originally Posted by Tyler Townsley

They make a DIS module checker, I have one but you might find one local as it will check a LOT of cars with these modules. You also need a scope to watch the spark as you change rpm. The advantage of the checker is you do not have to pull the plenum to check them. I had a problem with one that did not show up until 400 rpm where it began to fall apart. The dis modules are expensive when you can find them.

Re read the thread. To answer a question asked early on and never answered. The O2 sensors information is not used in WOT or power enrichment situations, the ecm jumps to calibration tables that are in the chip. The sensors used in the LT 5 are narrow band and the readings are only accurate in a VERY narrow range around stoic afr 14.7. Any voltages beyond this point high or low are meaningless. The dis module is subject to heat hense the type of grease they used when mounting it to the bottom of the plenum, it was there to promote cooling as the airflow through the plenum cools the plenum base as you drive. Not using this grease when removing/replacing the module begs for future failures. If you want to borrow my checker let me know I have lent it out in the past.

Tyler

Tyler,

Any chance you have a pic of this DIS checker?

[Pete]

Originally Posted by GregCrowe

Well, in this case it is sh!t. The car did the exact same thing before the plug change and after it. Same with plug wires, same with the fuel filter, same with injectors, same with fuel pressure regulator. Plugs are gapped at factory specs........ don't remember what that was, been over 2 years.

Plugs i would gap at .035 no matter what year Z you have.

The other question still remains.
"What plugs do you have?"

I asked you this 2 years ago and never got an answer and am still asking.

I hope not the Bosch Platinum,if so change them to AC Delco 41-602 gaped at .035

Plugs are cheap and easy to change.
Coils are more $$$ and harder to change.

Also can somebody take there Z with stock rear gears for a ride and tell me what RPM your at in 5th gear at 20 MPH, mine is all apart.

Help us help you.
Pete

[Tyler Townsley]

OTC 3575 or PRI Ignition System Simulator

Tyler

[GregCrowe]

Originally Posted by Pete

Plugs i would gap at .035 no matter what year Z you have.

The other question still remains.
"What plugs do you have?"

I asked you this 2 years ago and never got an answer and am still asking.

A/C Delcos before, A/C Delcos after. No change.

[gbrtng]

Greg:

Please describe "cutting out". Does the engine completely die and then recover when you lift from the accelerator pedal, bog down under full throttle and then recover, or miss heavily or slightly and then recover? I think you said earlier that power key selection does not matter. Please confirm - we're here to help, honest.

[John Boothby]

Originally Posted by Pete

Plugs i would gap at .035 no matter what year Z you have.

The other question still remains.
"What plugs do you have?"

I asked you this 2 years ago and never got an answer and am still asking.

I hope not the Bosch Platinum,if so change them to AC Delco 41-602 gaped at .035

Plugs are cheap and easy to change.
Coils are more $$$ and harder to change.

Also can somebody take there Z with stock rear gears for a ride and tell me what RPM your at in 5th gear at 20 MPH, mine is all apart.

Help us help you.
Pete

This morning, my '90 ran 650-700 RPM in 5th at 20mph.

[GregCrowe]

Originally Posted by gbrtng

Greg:

Please describe "cutting out". Does the engine completely die and then recover when you lift from the accelerator pedal, bog down under full throttle and then recover, or miss heavily or slightly and then recover? I think you said earlier that power key selection does not matter. Please confirm - we're here to help, honest.

OK, in complete detail:

When the car is cold or even just warm and being driven for the 1st 15 minutes, no issues whatsoever, even with full throttle. After the car has been driven and has sat, heat synching the engine, the miss begins. Normal driving with light throttle, no issue. When a load is applied, the miss begins. The miss is very "electrical" feeling. It does not come and go under heavy fuel delivery situations. It's just a very quick electrical miss and shudder. The car never dies nor does it even come close to dying. Again, it's only under medium to heavy load. If you want to make it miss the absolute worst, let it heat synch and then bog it down in a high gear at low speed and floor the gas. Then the car will shudder and jerk. If you try to accelerate through the gears at full throttle, the car just plain misses like it has 2-3 bad plug wires arching.