Serious Concerns Over Parts Availability

[secondchance]

Originally Posted by KJL

Update: I still have not found a solution to the code 43 (Knock sensor). I just started to actively put the issue to bed. The sensor harness volts checked out OK and the resistance to block is also OK. Marc H. has been nice enough to assist with trouble shooting this. One possibility is after the car reaches running temp and is moving, the ECM runs a self diagnostic by generating a knock to check the knock sensor is functioning. It is possible this knock is not being picked up be the sensor and the fault code results. The code is generated when the coolant reaches about 200F like clock work. I have an ALDLdroid data scanner and it confirmed there was no increase in knock count when the code was generated but the engine was retarded by 7 degrees once the check engine light appears sooooo…… I have a knock sensor on order from Jerry and Marc is researching the issue to see if there are any programable options.

Torque spec for knock sensor I believe is 14 lb-ft. Check the manual to be sure.

[Subfixer]

Originally Posted by KJL

Update: I still have not found a solution to the code 43 (Knock sensor). I just started to actively put the issue to bed. The sensor harness volts checked out OK and the resistance to block is also OK. Marc H. has been nice enough to assist with trouble shooting this. One possibility is after the car reaches running temp and is moving, the ECM runs a self diagnostic by generating a knock to check the knock sensor is functioning. It is possible this knock is not being picked up be the sensor and the fault code results. The code is generated when the coolant reaches about 200F like clock work. I have an ALDLdroid data scanner and it confirmed there was no increase in knock count when the code was generated but the engine was retarded by 7 degrees once the check engine light appears sooooo…… I have a knock sensor on order from Jerry and Marc is researching the issue to see if there are any programable options.

I have the exact same problem in my 92. Running out of parts to throw at it. Knock sensor already replaced. Same results with voltage and resistance readings. All connections to the ECU have been checked for continuity to each sensor. Same symptoms and readings on ALDLdroid. The 7 degree retard is the ECU going into safe mode. The only parts I haven't replaced are the O2 sensors, as one is intermittent 0.0 volts (with no code set), MEMCAL chip (although I removed Mark's piggyback and used the stock chip with no change in symptoms) and the ECU.

[Z51JEFF]

In general GM only supports replacement parts for 8 years then the parts are no longer made. It’s pretty sad when you can’t get a part for an 8 year old GM product but you can to a V.W. dealer and buy new bumper brackets for a 30 year old bug.

[KJL]

Update:
After some additional testing it was determined that the knock sensor circuit located in the memcal chip was not detecting knocks at all. Repeat attempts at using a steel rod and hammer could not produce a recorded knock even with the new knock sensor. I sent the chip to Mark and he confirmed my ALDLdroid readings as being correct. He replaced the knock circuit and verified correct function and returned the chip to me. No more code 43. I have not yet verified with the ALDLdroid knocks are being received using a rod and hammer on the driver side exhaust flange but chances are good all is well as it would not be passing the self knock system diagnostic otherwise. Lesson learned here is to collect as much data as possible to assist the experts like Mark diagnose the problem.


Also, the knock sensor does not penetrate the water jacket so no need to worry about losing coolant.

[davidijaxson]

I have been shopping for a ZR-1 and am getting ready to head out of state to look at one and pull the trigger if all is as expected. The car is in great shape, a 1990 with 28k. However being 30 years old I realize that things can break at any time. Given this thread I am having concerns that maybe making the purchase is not the best decision to make. I am sure most of you have had your car for some time. Would you purchase a ZR-1 now giving what you know about parts availability and probably a myriad of other things I am not aware of. I appreciate any input.

[Dynomite]

Originally Posted by davidijaxson

I have been shopping for a ZR-1 and am getting ready to head out of state to look at one and pull the trigger if all is as expected. The car is in great shape, a 1990 with 28k. However being 30 years old I realize that things can break at any time. Given this thread I am having concerns that maybe making the purchase is not the best decision to make. I am sure most of you have had your car for some time. Would you purchase a ZR-1 now giving what you know about parts availability and probably a myriad of other things I am not aware of. I appreciate any input.

Parts are readily available........there is NO Myriad of other things....
I do a standard top end restoration (see signature) and replace all fluids with the best (SAME FOR ALL ZR-1s)....

The LT5 is the most fun, most reliable and most unique engine around.

[lfalzarano]

I’ve had mine for 20 years. I keep it stock and I expect things will fail over time. Batteries and tires are the big expense. Parts are available from many reputable sources. There are many experts in this group and some offer rebuilding parts as a service. They are great and not expensive. Most of the ZR-1 is basic C4. The engine obviously not.

So if the care looks in great shape and the engine is clean, you could pull the trigger. If you provide the location, maybe a member could drop by and look it over with you.




Sent from my iPhone using ZR-1 Net Registry

[lfalzarano]

BTW - take it for a test ride. Nail it and once you hit redline if you are not smiling from ear to ear, look for another car. JMHO.


Sent from my iPhone using ZR-1 Net Registry

[spork2367]

Originally Posted by davidijaxson

I have been shopping for a ZR-1 and am getting ready to head out of state to look at one and pull the trigger if all is as expected. The car is in great shape, a 1990 with 28k. However being 30 years old I realize that things can break at any time. Given this thread I am having concerns that maybe making the purchase is not the best decision to make. I am sure most of you have had your car for some time. Would you purchase a ZR-1 now giving what you know about parts availability and probably a myriad of other things I am not aware of. I appreciate any input.

Now the more pragmatic response (maybe a bit cynical). If you want a fantastic driver's car, are willing to live with slightly higher maintenance costs, and aren't overly concerned about originality. Go for it.

If originality is important, that will be hard to maintain on a driver's car as there are some replacement parts that no longer have OEM replacements. When it comes to engine parts, Jerry's is really the only reliable source. When people say "many sources" that really only applies to the non-zr1 specific parts.

There are a very small number of parts that can be very difficult and expensive to replace/fix. DIS modules come and go on ebay, but they aren't always out there. There have been few failures, but the average mileage for the entire population of zr1's is probably in the 20-30k neighborhood, so not really failure point yet. Don't know where Jerry is at on his replacement.

Transmissions are also expensive, zr-1 specific, and tough to find. Most are repairable.

Body panels from the doors back are specific and getting harder to find. I know no one buys a car planning on wrecking it, but accidents happen (often by other drivers).

You could have 80-90% as much fun in a modified non-zr1 C4 or lightly modified C5 for a fraction of the cost (of buying and maintaining), but the zr-1 has an allure to it that is hard to resist.

[DRM500RUBYZR-1]

"Would you purchase a ZR-1 now giving what you know about parts availability and probably a myriad of other things I am not aware of. I appreciate any input."

David, this is not directed at you.

I have heard these same words for over 25 years now.
Yet I know of very few, if any, sidelined cars over a lack of parts.
Perhaps a lack of proper diagnosis at the moment, but not lack of parts.
Reminds me of a movie......................

https://www.youtube.com/watch?v=VUBFCaWiQ28



Marty