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Discussion Starter #1 (Edited)
My 82 280zx automatic non-turbo is at a repair shop and mechanic is telling me that the ECU is corrupt (not sure what that means). When starting the vehicle, the system dumps incredible amounts of fuel past the rings of which "washes out" the oil sealing of which has substantiated three complete oil changes w/filter. Can someone help me pinpoint the cause and how to resolve it? I read on this forum that ECU either works or it doesn't. Its only function is to regulate engine fuel and control. Thanks
 

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what did you take the car in for in the first place? what was wrong it originally?
did he actually test the ECU? probably not. you can't hook any computers up to these old cars, however you can test the ECU with a multimeter and see whats functioning or not.
so you're getting too much fuel? maybe your injectors are stuck open. the ECU will regulate how much fuel is needed and what not. do you have access to a junk yard in your area?

are you seeing blue smoke when starting and running? its possible that you may have bad or worn out piston rings. ask him to perform a compression check on all six cylinders and get the numbers.

Bon
 

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Discussion Starter #3
what did you take the car in for in the first place? what was wrong it originally?
did he actually test the ECU? probably not. you can't hook any computers up to these old cars, however you can test the ECU with a multimeter and see whats functioning or not.
so you're getting too much fuel? maybe your injectors are stuck open. the ECU will regulate how much fuel is needed and what not. do you have access to a junk yard in your area?

are you seeing blue smoke when starting and running? its possible that you may have bad or worn out piston rings. ask him to perform a compression check on all six cylinders and get the numbers.

Bon
The car is at a shop for total restoration. The engine and transmission were rebuilt. A donor car was purchased for missing parts. The ECU was installed from a donor car. I guess my mistake for picking a shop with little expeneince with the z rebuilt.
 

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The car is at a shop for total restoration. The engine and transmission were rebuilt. A donor car was purchased for missing parts. The ECU was installed from a donor car. I guess my mistake for picking a shop with little expeneince with the z rebuilt.

ah, I see now. well in this case, it is entirely possible that you have the WRONG ecu for your car. what year and model specific is the donor vehicle? as far as I know, the 83 car should have an 83 ECU, the 82 with an 82, turbo with a turbo, NA with NA, etc... unlike a 300zx, which you can swap any of the ECUs with any year. except for the 88-89, and as long as you stick turbo with turbo and NA with an NA.


if your car is an 82, get an ECU from an 82, non-turbo automatic car.


Bon
 

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Discussion Starter #5
Thank you so much for your reply! Both the cars are from the same year but there is a possibility that ECU is of different year as the donor car was a basket case. Any one have an ECU for a 82, automatic non-turbo for sale?
 

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Discussion Starter #7
Thank you so much for your reply! Attached is picture high lighting the JECS numbers compatible with an 82 280zx non turbo that I was able to obtained from a vendor. Based on it, one can use the same ECU for both manual and automatic transmission for a 280zx. May be this information will be helpful to someone else on this forum in case they are in the process of restoring their 280zx models. Once again thank you for your help!
 

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Just curious -
How do you know it's 'dumping incredible amounts of fuel' into the cylinders?
Does the motor actually start and run correctly otherwise?
 

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Discussion Starter #9
Just curious -
How do you know it's 'dumping incredible amounts of fuel' into the cylinders?
Does the motor actually start and run correctly otherwise?
This mechanic is telling me that it's dumping incredible amount of gas - 3 gallon in five minutes and he had to change the oil three times so far. I'm not sure what to believe as the car is with him now for 2 years for a total restoration.
 

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What? That makes no sense. I couldn't find 'gallons per hour' rating on a Z fuel pump, but would guess that 3 gals in 5 mins might be about the capacity they do. In other words, if you ran a hose directly off the fuel pump into a bucket, that's how much it would pump. For it to do that INTO the engine. . . WTF? I don't think you could physically get that much past the rings that quickly even if you wanted to. Plus if I saw or suspected that that much fuel WAS somehow getting into the motor (and hadn't blown myself up), I would sure as **** not let it keep up for five minutes!
And not even the stupidest mechanic on earth would repeatedly pump raw fuel into a newly rebuilt motor, then drain all the contaminated oil out, refill it and do it all over again expecting a different result.
Not to add insult to injury, but I also seriously doubt this has anything to do with a faulty ECU. From the outside looking in, it looks a lot like a scam to get as much money out of you as possible.
I hope that's not the case.
 
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