EPROM ECU Question
spyderturbo007
09-14-2005, 11:24 AM
I know that when you install a EPROM ECU in a 96 - 99 eclipse you have to reverse the order of the plug wires on the coil pack, but what if we go backwards.
For example: A buddy of mine (owns a used car lot) may be acquiring a 95 GSX. If I were to remove the ECU, provided it is an EPROM, and stick the ECU from my '97 Spyder in the GSX what would I need to do?
Would it be as simple as swapping the plug wires on the coil pack on the GSX? Would this cause a CEL? Could I guarantee him that the GSX would run just like it did when the 95 ECU was in there?
Also, I know that the injectors are out of phase, but what problems does that cause?
Thanks!
For example: A buddy of mine (owns a used car lot) may be acquiring a 95 GSX. If I were to remove the ECU, provided it is an EPROM, and stick the ECU from my '97 Spyder in the GSX what would I need to do?
Would it be as simple as swapping the plug wires on the coil pack on the GSX? Would this cause a CEL? Could I guarantee him that the GSX would run just like it did when the 95 ECU was in there?
Also, I know that the injectors are out of phase, but what problems does that cause?
Thanks!
scottsee
09-14-2005, 09:22 PM
I don't know if the Spyders ECU's are compatable, I dont see why they wouldn't be! You will have to invert the CAS signal by swapping the plugs like you said. Unless the Spyder Injectors are diffrent sizes then the 2g 450's I can't think of a reasion why you would have to mess with anything else.
What do you mean, out of phase?
What do you mean, out of phase?
kjewer1
09-15-2005, 01:29 AM
The CAS signal is what is out of phase. Anything that is keyed off of that signal will then be out of phase. The coil pack firing order is part of it, but injector firing order is no different. It was my understanding that the ECU does sequential injection at idle and cruise, but goes to batch firing at WOT, but I can't remember if Dave Mertz said that was not true or not. At any rate, it has no effect on WOT performance. Just some rough running at idle and cruise, which some poeple never notice. I did notice it on my 95 when I went to a 1 CAS, so I spent about 10 minutes rearranging the injector wire pins at the ECU connector. I forget where I saw the instructions for this, but I bet it would be on either magnus' or RRE's page, maybe even in the vfaq somewhere. With DSMlink of course you can simply invert the CAS signal to avoid having to do this. Other than this stuff, there should be no reason the 95 ECU wont work in a 97 or vice versa.
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