300zx ecu

[sleepy3434]

Hi, I have a 1993 300zx na auto (american) car. I think my ecu is not functioning properly and am looking to pick up a used one. The only ones that I have found near my home are all jdm. Are these interchangeable??

[nissanfreak12]

No, JDM ones have a higher octane rating than USDM. I believe they use 94.

Why do you say your ecu is not functioning properly

[sleepy3434]

Car was driving fine when I parked it in my garage. A week later I go to take it out. when I put the key in the on position(not start) the electric fan and engine light come on now. The car will start but is not idling right and does not drive properly. The electric fan never stops running until I turn it off. I pulled back passenger carpet and tried to run a diagnostic on it. The light is on but will not flash the codes. I had local mechanic swing by and hook it up to his machine. It was not able to access the computer. we tried short out the pins as well . no luck. He tells me he thinks it is the ecu.

[DCaff300ZX]

Hmmmm, very odd.
I have an USDM NA AT ECU I could sell you if you want it, pm me for details. Where are you located? (for shipping costs)

[sleepy3434]

I am unable to pm you???

[DCaff300ZX]

I am unable to pm you???

Ah, since you have been here so little (3 posts) you don't have pm ability yet.
You can e-mail me directly at [email protected] in regards to this, I'll look for you.

[itsa300zx]

No, JDM ones have a higher octane rating than USDM. I believe they use 94.

Actually, Japanese gasoline and northamerica are pretty much the same, given the same grade. Japan and many other countries just list a different octane rating number than North America. There are 3 types of octane rating for any given grade, I'll use premium as an example.
RON rating is 97,
MON rating is 87-88,
AKI is average of the two 92-93.

North America gas stations list anti knock index AKI average of RON+MON
Most of the rest of the world list only RON at their gas stations.

Therefore, a RON 97 in Japan has the same knock resistance as a North American rating of 92-93

Hope that helps.

[nissanfreak12]

No, JDM ones have a higher octane rating than USDM. I believe they use 94.

Actually, Japanese gasoline and northamerica are pretty much the same, given the same grade. Japan and many other countries just list a different octane rating number than North America. There are 3 types of octane rating for any given grade, I'll use premium as an example.
RON rating is 97,
MON rating is 87-88,
AKI is average of the two 92-93.

North America gas stations list anti knock index AKI average of RON+MON
Most of the rest of the world list only RON at their gas stations.

Therefore, a RON 97 in Japan has the same knock resistance as a North American rating of 92-93

Hope that helps.

That makes sense, but that still leaves us with not many states have 92-93 octane. Also, was this the same standards 25yrs ago?

This would also be the equivalent of running mid-grade gas when you should be running high. Just a thought.