BP26 ECU on BP-T not working

[Jovian2k]

So I finished by BP turbo swap on my MX-3. I went to start and it turns over but won't start. I'm using BP26 ECU. I plugged by BP ECU back in and it started right up. I want to use my BP26 ECU what could be the problem? I have a B6 ATX harness, 4 wire TPS I figured it would work fine and that would be an issue... any thoughts?

[RobMinhas]

Is the BP26 ecu a known good unit? Is there anyone close by who has a working one that you could use?

[Jovian2k]

May not be, nobody around that I know of but I guess I'll be on the hunt for a working BP26 ECU and see...

[RobMinhas]

I have three if you need one, all guaranteed to work. You cover shipping to and from and I'll send one your way to see if it works, if theres no one closer.

That being said, I think AaronTietje/Rising Sun is down by you and he may have a BP26. Can't remember exactly where he is located though.

[Jovian2k]

PM'd.

At first I thought maybe it is because my 4 wire tps + na harness required me to move ecu pin 2L TO 2M (read a post about it but maybe not necessary for my application) but I tried and it did nothing.

[Jovian2k]

Any thoughts? If I tried the 2l to 2m pin switch and still no luck amd I likely dealing with a dead BP26 ECU?

[Jovian2k]

So I have a MX-3 B6 ATX Harness... when I did BP swap I used ATX BP ECU (would not run with MTX BP ECU). Now that I am trying to run a GTX ECU it won't run...

I am thinking I am kind of screwed because of the differences in the NA ATX harness pinout and GTX pinout. Not impossible but it is almost COMPLETELY different pinouts!! http://www.wihandyman.com/forum/show...nouts&p=504283

Anyone else do this (b6 ATX -> GTX) or have any input?

[MazdaNoob]

if it runs on a BP ecu it will run on a bp26 even without changing the pinout ... not well but it will run

[Jovian2k]

But look at the link above, the 3 plug NA ATX Harness pinout is very different from the GTX pinout. Seems to require many re-pins

[Jovian2k]

Here are the swaps I have determined I will need to do...

[MazdaNoob]

damn .. sorry for some reason i skimmed over the AT portion of that ... well .. grab a coffee, a pillow , some soft music, and get to repinning that bitch

[Jovian2k]

damn .. sorry for some reason i skimmed over the AT portion of that ... well .. grab a coffee, a pillow , some soft music, and get to repinning that bitch

Haha Love it, you better believe I will! No turning back. So there will be many pins from the ATX b6 Harness that will not be used (as would be expected with the ATX), but everything else matches up nicely.

[Jovian2k]

So replaced all of the above stated pins (pain in the ass) and it started right up! Re-pinning is no fun, tough getting the pins out of the harness without ripping them out and breaking piece of yellow plastic that grabs onto metal clip to secure it in harness. Had to switch some of the pin types as well since there are sm/lg pins and some re-pinning meant switching pin types. Wiring is a mess too since wires from my 3 ATX plugs are all crossing over to different plugs + new connections I had to make... wish I could clean it up maybe sometime down the road.

Seems to run well, just need exhaust now. Hope my wiring mess is intact and doesn't cause any problems... I planned carefully hope that worked in my favor.

Heres the final re-pin cheat sheet...

[atomicEGT]

nice.