[RESOLVED] Help Installing Eprom ECU

[jm1080]

I was thinking of ordering an Eprom ECU non socketed from a member. Ive searched threads and couldnt find what I was looking for. First of all its from a 95 GST, I have 97 GSX. If I just swap them, what do I have to do? In order for it to work on my GSX? I dont have DSMlink yet, but I just want to swap them. Anything I have to look for?

Also does anyone have any instructions on how to install/swap ECUs? Thanks!

 

[livedsm4g63]

why do you want to swap the ecu's? you dont have dsmlink.

 

[robbo185]

I wouldnt swap until you get dsmlink that is assuming you're getting dsmlink. When you do get dsmlink you would have to take and swap the ecu's out again so you can get it socketed.

Also I think the only thing you have to do is switch spark plug wires around. Switch 1and2 and 3and4 and it should fire up.

 

[jm1080]

Im switching them because I want to learn how its done....Im also getting a CEL on for rear o2 sensor everyday and If I switch it would remove it, since its a 95 ECU.

So I just have to switch plug wires around? Does anyone have a link or actual instructions on how to swap? Thanks

 

[rock0134]

It isn't hard. take off the center council and kick panels.

take off the 3 or 4 bolts and unplug the harnesses. Done.

 

[snowborder714]

You need to do a bit more than swap plug wires.

What does CAS inversion mean?

For 1G DSMLink, nothing. For the 2G guys, the '95-'96 style Cam Angle Sensor (CAS) sends out a signal that's electrically "inverted" from other DSM cam sensors (1G or '97+ style). When you put a '95 ECU into a car with a non-95 CAS, the ECU ends up swapping the firing order of the injectors. In most cases, this produces very little noticeable difference in drive quality. But we offer the option to invert the CAS signal anyway just in case. You can selectively invert this signal with the DSMLink software as you wish. You will still need to swap your spark wires, though. We can't control spark firing order in the EPROM at crank time. So even with CAS inversion, you still have to swap plug wire 1 with 2 and 3 with 4.

You can invert the CAS signal via DSMlink, but the only way to fix this without link is to swap the injector wires at the harness. As they stated, it won't produce a huge difference in driving (I don't know about this from first hand experience though). But between this and removing it again to get socketed, the only way I'd install the EPROM is if you plan on selling/swapping/getting rid of your stock ECU. If you still plan on keeping the stock one, just put the EPROM away until you plan on purchasing DSMlink.

And as for actually swapping the ECU's:

1. Remove both side panels in the foot wells so you can access the ECU (located below and behind the radio).
2. Remove the 4 plugs from the ECU via the drivers side foot well.
3. Remove the 2 bolts from the ECU via the drivers side foot well and the 1 bolt via the passengers side foot well.
4. Remove ECU.

If you'd like some pictures, let me know and I'll go quick take them.

 

[turbosax2]

Don't forget to disconnect the battery before messing with the ecu - *just to be safe*.

 

[jm1080]

I wont be using the stock 97 ECU no more because of future use in DSMLink. But i still want to get it out of the way and install the 95 EPROM so CEL for the rear o2 will go away as well.

But let me get this straight, I:

a) disconnect battery
b) unbolt stock ecu
c) unplug stock ecu
d) install eprom ecu
e) plug the plugs back in
F) and then switch around injector plugs to invert cas signal

Correct?

How do I switch around injector plugs? Like which plugs go where?

Thanks.

 

[housegsx]

I did this with a stock eprom ecu before sending it out to get socketed. You definitely need to swap the plug wires. My car was still running pretty rough at first due to the different CAS signal or the ECU was just relearning itself or whatever. It progressively got better after 1/2 hour of driving.

There is no point in doing this though if you aren't going be going with dsmlink or the likes soon.

 

[jm1080]

yea it seems like a lot of work just to get rid of CEL . Might as well live with it and install EPROM once I get DSMLink right?

Lets say once I get DSMLink and I install my EPROM Do I still have to switch spark plug wires and injector plugs to invert CAS signal? Or does DSMLink do all that without me changing anything?

 

[housegsx]

You still have to swap plug wires. The CAS signal can be inverted within dsmlink.

 

[livedsm4g63]

how do you know the cel away? what if it is the o2 sensor?

 

[jm1080]

how do you know the cel away? what if it is the o2 sensor?

The CEL is from the rear O2, I eliminated the cat, so now the CEL comes back on. 97+ ECUs would detect if there is no cat and with a 95 ECU it wouldnt detect it. And I dont really want an O2 simulator or go through all that trouble. Since I need a 95 ECU for DSMLink I was thinking I might as well buy it now since I can.

 

[BoostFrenzy]

And I dont really want an O2 simulator or go through all that trouble.

It is really not that big of a problem. This is all you need and it's only like seven bucks.