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Hi all,

I have a series 1 r33 manual with all standard mods. I sourced a new ecu which has been remapped. when the new ecu is plugged in problems arise...

Start car. This seems fine, idle high on cold map as expected. Note i have not tried revving the motor.

Now, here is the really weird bit. When moving the gear stick from side to side revs drop like a small miss and i hear the fuel pump cut out and turn back on. Now clutch in and select a gear and bang she stalls (clutch still in). engine check light is now on. Car needs to be turned off completely to clear engine check light.

Now with motor not running and ignition on (car turned off fully to clear engine check light) i move the gear stick as described above and can hear the fuel pump start priming again. So i switch on keys till red lights on dash (fuel pump primes) then after the fuel pump stops priming i move the gear stick to either the left or right and the fuel pump primes again. Something seems top be triggering this.

I unplugged the new ecu from the loom put my old ecu back in and she works.. Replugged the new tuned ecu into the car ensuring loom was connected tightly and this same thing resulted.

Is there some kind of switch around the gear box which sends signals back to the ecu?

OK ECU serial numbers etc

New tuned rom ecu (problem ECU)

23710-21U01

MEC-R521 A1 4321

Old standard ecu (Working Fine ECU)

23710-21U01

MEC-R521 A1 3X22

Any help would be much appreciated.

Edited by turbs33

I know on my z32, the ecu raised the revs as soon as the gearstick was put into gear. Maybe try checking the wiring diagram to see if there is a sensor(im betting there is)You could try unplugging whatever wire detects that, if its the only problem with the ecu, you may have to live around it.

sounds like the map in the ecu is corrupt, when the neutral position switch is turned on/off (by moving gear selector) its turning fuel pump on and off.

the auto ecu uses this switch to raise idle up and down for when it goes in gear.

the ecu map is corrupt mate, and its using that input to do something other then it should.

or other alternative is the ecu is from another nissan vehicle that uses a different pinout.

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