Okay if there is someone who can crack this case, here is the deal. -
I own a 85 RX-7 which recently I put in a 89-91 TII motor. I built the motor with street porting (primary's and secondary ports). I'm running all the sensors except for the air control valve. I had to use a 1st gen cover which doesnt support the electronic metering pump, so I'm not running the OMP , but its still plugged in on a bracket off to the side. I'm using pre-mix.
I was told that It would run fine as long as I left it plugged in, but is doesnt, not at all. Its really rough running and really rich when its plugged in , and you have to give it alot of gas until around 3k-4k the turbo starts to spool and it smooths out. Its a new motor and I hate to even risk the chance of boost, but its the only way it would run (dont worry it was less than 1psi).
I then unplugged the pump entirely and it runs much better, and smooth, but will only idle at 2k not any lower. I've been driving it this way, and it works, just I cant give it very much gas or it will stall out.
I know both are a sign of a "limp home mode" from the OMP not being attached to the motor.
IS THERE ANY WAY TO MAKE THIS WORK!? I dont want to fab the TII front cover if I don t have to.
Is anyone out there with a 89-91 running pre-mix? If so HOW are you doing it?
Before anyone asks, I have a walbro pump, brand new injectors, new filters brand new plugs and wires, the timming is right on, and I have checked leading and trailing are working perfect. The turbo is brand new, with a full three inch exhaust. I dont have the FCD on yet since I'm not running boost yet. The oxygen sensor is new too.

SOME EXPERT HELP ME!!!!

 

it is impossable to trick. there is 9 wires. you would have to build a black box with advanced circuits to fool it.

the best thing anyone has done is pluged one into the harness. and tied it somewhere else under the hood. the ecu still thinks it's pluged in.

I would reset your ECU to clear the codes with it pluged in. and try driving again.

if you are getting an OMP code with it pluged in. I would suspect bad wiring or OMP. it still has to be a good one even though it's not being used.

 

Talk to Aaron Cake he said it woudn't be too hard to make something up for it to be bypassed but doesn't want to do it since he has no interest in that.

 

Loosing the S5 ECU is the solution.