2002 QX4 FLOODED-CHANGED ECU WITH ONE FROM A PATHFINDER,BUT NUMBERS DON'T MATCH

[DAROCK79]

Hey guys ! I am new to this forum and need some help. Any help would be great. I am working a 2002 QX4, that was flooded. I change the main ECU and it is running. When it starts when cold, the RPM is at 2000, then when the engine gets warm its revs up and down between 2000 and 2500 RPM. So I am thinknig I got the wrong ECU in the truck. I got one off an 02 Pathfinder, all the numbers match from the old ECU, except the last four digits. So I think my best bet is to get one with all the numbers matched-?

[elwesso]

No i really dont think that will make any difference... ECUs from the same vehicle but slightly different build dates will have different numbers...

You probably have some sort of other electrical problem.

[DAROCK79]

Should I change the engine harness.-? The main problem that I am having now, is that when the engine gets warm, it surges between 2000-2500 rpm. So if its not the ECU, maybe I should change the harness-?

[elwesso]

i dontk know what woudl cause the engine to do that, that woudl be related to the harness...

are you getting any codes?