Happy to finally start contributing here.
I bought my 1994 Montego Blue FD in October of 2023, and have been a part of the rotary community through my friend and roommate for nearly a decade. I like to tinker and come up with solutions to problems, which makes this car a very fun thing to work on for me. I have hit a couple walls with troubleshooting, so I am hoping to find some advice here for some more obscure issues.

 

Welcome! Beautiful car you have.

I won't call the cops for parking in the fire lane.

 

Thank you!

Funny enough, I think that's intended to keep you from parking in front of the space. Otherwise there would be no where to park in that whole lot! :P

 

Welcome to the forum!! Montego Blue is one of my favorite colors on the FD amd your car definitely does not disappoint! Does your car have the black interior or tan?

 

Welcome to forum

 

Montego blue is also my favorite :P

It had tan seats and carpet. The panels are all black. I replaced the seats with the black suede ones, and have black floormats to reduce the tan carpet.

 

welcome. what issues are you having?

 

I'll post about it in a more troubleshooting specific thread, but in short just for those curious:

The car intermittently runs very rich, loses power, and backfires/flames out of the exhaust on decel. Goes away when I restart the engine. Comes back after an unspecific amount of time driving. Haven't figured out anything consistent that causes it to misbehave. Been dealing with it for almost 2 years since I installed Power FC. I've replaced the PowerFC with a new one and still have the same problem. Both S7 PFCs (from the newest model). I've done a LOT of troubleshooting, and still have some things I want to try before I make a big post about it.

I'd be happy to provide more detail, but I don't want to muddy the spirit of the intro section. I appreciate your interest.

 

i see.... yes, when you make that thread please be VERY detailed on all mods and everything you've done to the car. also mention everything you've replaced or checked. pull the tune and post that as well. you can attach files to posts

 

I've been building a post for a couple days that details everything and in the process realized I couldn't remember some things I've tried so I need to go double check some things now :P

Thanks for the guidance

 

Can an S7 power Fc work in a 1994 USDM car? If S7 is the equivalent of FD Version 4, Mazda made quite a few changes upon the introduction of Version 4 cars, including a 16 bit processor.

 

Apologies for the confusion. I meant part number 414-Z007, so Mazda RX-7 Ver. I-III.

 

Depending one how much change your car has, you could try putting the stock ecu back in and see if you get any check engine codes.

 

Welcome to the forum, and good luck with troubleshooting! Have you had anyone tune the PFC since you put either the old or new one in?
You might do a quick sanity check on your PowerFC commander > "SETTINGS" > "REV/IDLE" and see if the RPM values for the three "F/C" settings are absurdly high or not.