I think it died anyway. two days ago I got in my 93 FD to go to work. the car fired up then promptly died. The PFC Commander is not coming on when i turn the key. I have 12.9 volts at the battery, I checked all the fuses and they are good, took the PFC out and checked for any burn terminals and made sure the connections where tight. I've had the car for a little over a month now and I'm still new to RX-7s. Its pretty heavily modded (single turbo, bigger injectors, FMIC). Has anyone experianced this before? Any Ideas? Anything you guys have would be helpful.
Thanks,
Corey

 

What injectors and how many injectors is the PFC controlling?

 

4 total, 1600 bosch secondary and 2 primarys that i dont know how big they are because i haven't had a chance to get that involved with it yet. i dont have any fuel pressure. the engine will turn over. i also checked the grounds that i could find. i gonna go thruogh the FSM and see what i missed.

 

make sure you didn't overlook the engine fuse inside the cabin by your left foot.

 

that was the first thing i checked, but i will check again just to make sure.

 

nope not that fuse.

 

take a hammer to it!

well maybe not, try to find someone with another test shell car and swap it out to rule out the ECU as being faulty.

 

Check the 30A EGI fuse in the engine bay, also check the EGI main relay

 

karack, i'm not to the point of being mad at it yet, the thing is, i'm the only one i know within 60-70 miles that has an FD. maybe theres someone hiding out in the florence SC area that i don't know about?
Banzai, I shall recheck those fuses tomorrow. Thanks for the advice. I'm going to get to the bottom of this.

 

30 amp fuse was blown. had to check it with my DMM because the clear plastic window was so hazy. thanks agian fellas.

 

well the fuse was blow but still no start. checked the main circuit relay and engine relay and they both work. anything else to check before i break out the test light?

 

blown*

 

does it keep blowing the new fuse you install? sounds like you have a short in the ignition or injection circuits. see if the PFC commander is showing signs of life, if the fuel pump is priming when you turn the key on, check for spark/fuel, etc.

 

Most of the fried Power FC's I see are as a result of not having a driver's side fender liner installed. This allows water to spash up on the diagnostics box and often times the wheel rubs through the harness. So the question is, does your car have fender liner installed?

If the 30A EGI fuse was blown there is a good chance the EGI main relay is toast too. swap it for the fuel pump relay right next to it and report back.

 

the fender liners are not installed (shame on me), they didn't come with the car. I will check the harness and daignostics box, plus swap relays tomorrow. It probably did get wet because I washed it with the hood popped (but not fully open) the night before it quit.

Karack, I'm not getting anything as far as fuel or spark, no pump priming, no fuel pressure, all it will do is turn over.

 

Jack up the car on the driver's side and look for harness damage above and in front of the wheel. Just letting you know this is not going to be an easy fix.

 

Hey, I just bought the harness adapter from banzai and I'm going to put a PFC into a vert, if I try to water-proof my pfc will I cause it to overheat? I'm not sure how hot these things get or if it needs airflow.

Before this I have a megasquirt in a vert and that thing literally went though hell, I'm pretty sure it actually got sumberged in water and kept going, lol.

 

swapped out relays and the pfc came on! but when i treid to crank it the fuse blew again. its about dark here in SC, and i have an immoblie mustang in the garage, so the wheelwell inspection ill be put off untill tommorow. I kinda figured it wouldn't be easy, nothing worthwhile ever is. I've got plenty of experience with fixing wires and other electrical problems, I just don't have much with RX-7s, or imports in general, but I'm learning.

 

You will not be able to start it without the fuel pump relay. You need to buy a new EGI relay, put the FP relay back into it's location. I think you are going to find wires shorting out in your wheelwell. Do not try to start it until you have sorted that out. Fix the wiring and hope that you have not fried the PFC. There is a good chance that sections of the PFC are shot, ususally I see issues with the MAP sensor reading and coil operation. Buy some fender liners to prevent addtional issues in this area.

 

my car ( shell I purchased ) had a driver side wheel well short and melted a bunch of cables from the harness together 9 I seperated the cables and will be putting in some relays / fuses as my car didn't come with any this weekend . is there something that commonly causes a short in that same area ? or is it just because of wet/ stripped wire conditions that cause the short ?

 

I understand that the car will not start without the fuel pump relay. The EGI relay will not be in to my local NAPA until Monday. I shall purchase some wheel well liners also. Thank you for the help and I will be purchasing a few things from Banzai Racing. I will let you guys know when I get it fixed.

 

i found this wrapped in about a roll of electrical tape

 

should be unrelated, that is for the impact sensors in front of the car for the airbags.

 

its gonna get fixed while I'm at it. I'vebeen inspecting the wheels wells and can't find anything out of the ordinary on the drivers side. Do any wires on that circuit run close to the parking brake? i'm trying to figure out what I did right before it stopped running, and I set the parking brake. maybe a wire got caught?

 

still not fixed. do injectors short out? looking at the wiring diagram it looks like the injectors are on that relay.