Follow-up: own a 1996 Discovery SE7, my engine ECU was replaced with an engine ECU from a 1997 Disco. After ECU replaced my 1996 idled @ 2500 rpm. The shop then replaced my TPS and re-adjusted my idle, now idles @ 500-1000 but hesitates & sometimes stalls out when starting from a stop. The check engine code reads: O2 sensor. Is this new stalling thing b/c the engine ECU is from a 1997? I can't get a straight answer from anyone (forums, Rover dealer, mechanics) if the 1997 ECU is interchangable w/ my 1996 or not? I know Disco Mike answered the ECU is not interchangable, but the parts guy with my Rover dealer states it is and other people are telling me that the car wouldn't work at all if the 1997 ECU was not interachangable.... I just emailed Land Rover USA corporate this and should have a reply in two business days. Please HELP.

My British mechanic friend has my car now and he's going to reset my idle back to factory to see if it goes back to 2500 rpms, to rule out the ECU interchangable thing. He also believes the TPS was not set correctly either and that may be part of the problem....and I know I'll need 4 new O2 sensors eventually but that shouldn't be part of this idle problem.

 

Just wondering if you found out anything about the idle issue...

Last week I had to replace my ECU and same deal.. I got the ECU and ECM combo from the same vehicle. Not sure if it was a 96 like mine or a later year but I have the same idle problem and was thinking of a vac leak or something as the truck sat a while....

Would appreciate any info

 

i had the same problem .. i have 96 d1 with the ecu # err6759 ..got water in it and tried replacing it with a what was supposed to be the same one but the guy sent me the wrong one that came out of a 97 and same problem ..stalls out idles or either idles wayyyy to high at about 2000 or 2500

 

The ECU's are coded to the Rover that they are put in.
That means that if you read the ECU it will tell you the Vin number of the Rover.
So a SE7 may work on a SE7 of the same year but not a SE.

This is how it works on all car's and trucks.
In Texas on state inspections that are OBDII they caught state inspectors that would do inspections on the side for more money, when they would plug in to another car to scan for codes but at the same time it would check for the VIN number and if it did not match to jail they would go.

 

You might also find that a dealer can reprogram your replacement ECU to your truck, I don't think many dealers know this and would suggest you contact your local Rover Distic office and talk with the technical people.

 

The gems ecm's are interchangable.I would recommend taking it to the dealer to have the adaptions cleared first. You may have to reset the base idle afterwards. clear all faults and go from there.

 

That is all correct. All GEMS ecus are interchangeable from one vehicle to another. However, one must indicate to the unit the correct model/engine it will be running and clear the adaptive parameters. The setup can be done if you have a diagnostic device such as Rovacom Lite. If you have Rovacom (or its more recent successor) there is a Manual on line I came across that can walk you through it. Or, you can try to find a Rover dealer who has a really well-trained fellow from back in the GEMS days.

James

 

So they are interchangable,,,,after the ECU has been setup for the LR thats its going in to.

Not just a plug and play from one Land Rover to another.
If I read this right.

 

Who has a rovacom? If your local dealership cant help you with your GEMS car, (in use till 89) Then you are trully screwed! I highly doubt it, however!!

 

typo (in use till 99)