3XAZOWNER

What is happening to all the ecu's that go bad? Are they being tossed or can they be rebuilt? My 83 has had a erratic idle and backfiring for several weeks now. I have changed out plugs, plug wires, rotor button, dizzy cap, cylinder head temp sensor with new, the afm, fuel pressure regulator and ignition coil from my parts car, but still it ran rich and popped and backfired. My cousin was in Ga from NY and I havent seen him in years. We began talking about cars and he told me he just sold one of his Z's. We talked about Z's for about an hour and he had asked why i didn't drive mine to the reunion and i told him about my problem. He said it is your ecu and it wasnt hard to change. I changed it out Sunday night and the car has ran perfect since then. My car is an 83 non turbo with 5-speed and digital dash. The ecu i pulled from my car had written in yellow 82 AUTO.(like it came from a yard). What matters when you match an ecu with a car?
does tranny matter?
does digital dash matter?
does turbo matter?
the one from my analog parts car said to use only in an 83 or the ecu could be damaged. Do i just pitch this ecu or am i helping them to become extinct except for the expensive new ones?
What are the rules of swapping, because if these are disappearing, i want to shelve a couple to use when mine goes out?
thanks for any info on this.

Bleach

did you ever try just unplugging and repluggin in the connectors on the ECU? Maybe it was just some oxidation built up on the plugs and it needed a re-seat. That happens often too. Your other ECU might be good still.

3XAZOWNER

No, Im not that bright, but i aint gonna chunk it since you mentioned that. But i aint gonna go back and try it,until i have to get back in there. Hadn't thought of that, good, no thats a great suggestion Bleach.
But does anyone know the rule of thumb to follow when crossing these ecu's from one car to another?

Bleach

I don't know every ECU trick but I do know that you should never cross any non-O2 sensor ECU with an O2 sensor using wiring harness.
So for your 1983 car, if you stick with 1981-83 you should be fine as far as I know. Don't go grabbing 280Z ECUs.

nismo619

I wish some body had a spare 82 or 83 ecu to sell me... by the wya does any body know about this called the " ignitor chip ? or about that little .5 amp fuse inside the main relay box ? does any body know ? private messege me please i need to learn more

lww

They're probably goin' in the trash, but it's usually a mis-diagnosis. These ECU's seldom go bad. Usually, it's corrosion build up in the electrical connectors.

I can say, I have never seen a LEGITIAMTELY bad ECU from one of these cars in 20 years of messin' with 'em.

Bleach

weird stuff: My Z wouldn't start today... I unplugged the ECU connectors and plugged them back in and it fired right up. Mabye part of my problem is corroded connectors. still runs crappy but at least it started. talk about taking your own advice!

PooFlinginMonke

They go to us, the ecu rebuilders, for about 12 bucks a pop or less.

We probably have 800 nissan ecus in the warehouse and we have 3 or 4 more warehouses around the country.

lww

How much do you resell them for?

PooFlinginMonke

We test them completely in every way on car simulators including heating them up and cooling them down to temps way beyond what they would ever see in the field and do any repairs, if needed.

List is $435 for a 1988 300zx turbo manual transmission car but jobber, of course, is quite a bit lower so a call to Car Quest might net a considerably lower price than $435.......but it may end up higher.

We also do testing of ECUs and I have found that only 10% of of nissan ecus sent in here are actually bad........unless somebody has a car with shorts to the point of burning up every ecu put into the car.

nismo619

Well what if u connect the car battery wires backwards and try to start up the car ? werid problem im having that ifound out what ever happend to this 83 turbo i bought must of been bad... burnt ecu not working. not working distributor. Poo Fling i hate to ask u this but have u tried to fry a ecu ? on a running car ? and if u did what all did fry ?

PooFlinginMonke

What I see that kills nissan ecus is a component like an ignition module (power transistor) shorted to ground or any other ecu controlled actuator that operates on higher current than you would find for just signaling.

Also anything that uses a reference voltage or is powered by the ecu can cause problems since the regulator in the ecu wants to insure that the reference voltage is always 5 volts. Some regulators will insure 5v until they burn out while others will just drop voltage if the load gets too high and you then recieve error codes referencing low vref.

With any ecu, first is to see if it is getting all the powers and grounds it needs and second is insuring it is sending the proper reference voltage to the sensors.

Once you establish that, you have to see if the sensor is sending the proper signal (a nice good square wave from the distributor/CAS).

Of course, even a working ecu will not help a car that has fuse link problems or has a bad relay.

Luckily for us, we don't have to worry about security being within the ecu or many here would be sending in good ecus as defective because they didn't read up on the proper proceedure to appease the security gods much like every ecu made for the big 3 since 1996.

23dobsona

do you have a 83 ecu i could buy?