Switiching ECU's 2003-2003.5+
 

Since I went FI I have had problems finding an ECU that will adapt to many of the aftermarket piggybacks or flashing devices. Ive decided that my best option is to swap ECUs out for a newer version g35 ecu. Now I can find a used ECU no problem for moderately cheap, I have having trouble finding the compatible harness and or any other parts I may need. has anyone done this before and if so what will I need?

I was told by Osiris that if this is possible they would love a write up as this would bring them more customers. Anyone willing to help?

I considered this many times. Not worth the cost and effort. ECU and wiring harness are different.

You are much better off just wiring up a piggy back. You'll save yourself time and lots of headaches. Not to mention money.

In the previous PM I sent you I had mentioned about the greddy emanage if you knew if that wired into the old style ECUS just fine, or if it just looked for the normal wires every ECu has. I know it cant access closed loop functions but I really dont have a choice other than that and Haltech... and I dont have that money right now.

Look at getting the Greddy Emamage Ultimate. Its a much better functioning unit for FI.

You can try the ECU swap, but my guess is that you'll spend a lot more money and tons of time on the swap. Maybe it will be easier than i suspect, but highly doubtful.

Another option is the UTEC and get the plug/play harness that the maxima guys created so it can be used.

I don't see why it'd be difficult. I found an 04 harness for my car that I ended up not using for $200. Shouldn't cost more than ~$300 to do it. Would be well worth it just so you can have more tuning options.

Its not an easy job swapping harnesses.

It isn't incredibility hard, and it would be worth it.

Im still waiting for returned calls to all the dealers and shops for assistance in this and slidegood has nothing :(. When I called shops to see if they could help, most of the time the guy on the phone had no idea what I was talking about.

I found a harness, Bought the ECU and found a cheap Utec for sale which I will then upgrade to a haltech when I get the money. The guy selling the harness will also give me instructions, I may do a write up with photos on a DIY when I get it depending how much time I have and how cold it is outside haha.

Cool. Do the write up for us :D