Unless you did the pinout procedure, I don't see how you could swap a stock ECU back in......because when I did my PFC, I simply cut the 4 wires that were no longer needed with the PFC, but a stock ECU would still need those 4 wires I believe. Maybe not though, not 100% on that.



I don't think it is a grounding issue, since it ran fine with those wires crossed....and those two wires are not going to ground the entire system, so I doubt that has anything to do with it. A noid light would be my first venture....make sure the injectors are pulsing. If so, then move on.....but don't overkill yourself and try and do 10,000 things at once. Start with the cheapest **** first. Injectors. What about your secondaries....are they wired correctly via resistors? I don't know if somewhere down the line they may share grounds with the primaries....but if they are wired wrong....it could feasably be shorting out the injectors if they are connected in some way....I don't think they are, but who knows.



I doubt it is the PFC as well....since again, it started with wires crossed, so that to me shows that the problem lies in the wires, not the ECU. Unless by some fluke chance the PFC has one bad solder joint in it on one of those injector grounds. Did you link the front rotor injector into the rear rotor injector or vica versa? Have you tried it the other way....make the injectors share the other ground and see if it starts....if so, then it is not either ground wire, but some type of wiring problem in the harness somewhere. I would think that one way would work and one wouldn't....but again, I don't know. Seems like quite the headache....don't worry, my car was down for 11 months and 23 days before she started back up again. Eventually you will get it, just don't stress out about it.



I had a problem on mine, when I gorunded some loose wire on the battery side of the harness.....since I did not know what it went to and it looked like a fat ground wire to me....but I was wrong, it was the AC power, which I had since removed. I had all sorts of problems until I found that out. Or another time, I forgot to link the battery fuse box with the main fuse box.....yeah, it is tough to start your car without any of the main fuses getting power as well. Point is, small **** will slow you down, but you will find out what it is and slap yourself on the head about it.

 

Thanks for all the advice. I'm going to get a noid light tomorrow and start from there.. I think a stock ECU will still work, but not positive. I know a few guys with PFCs that'll let me borrow them if needed. I'm going over the grounds again.. Just in case. I guess it cant hurt.. I just hope it's not the PFC. I can handle a few hundred bucks and a headache, but another grand for a computer I already have will push me to suicide! (Not really) Thanks for the time. It means a lot to be able to ask a question and actually get a n answer that was actually cared for when written. Hopefully I can return these favors someday!

 

justin...... let me know if you need a stock ecu..... i have one and i can send it to you to borrow if you need it

 

We had a customer that got a bad PFC not too long ago. He lives in CA so he stopped by APEX and they could not fiqure it out so they gave him a new unit.



-Ryan

 

You da man!

 

Crap really? That sucks.. Hopefully mine isn't bad, and if it is I can get something done about it...

 

not to be a shallow ***** but like sindwinder said man I don't see any reason a wire wouldn't have a break in it especially how hot it gets in the engine bay, like half the wires in my engine bay have to be touched and they just break the *** off! I got to rewire most of my ****, and the ecu well hopefully you didn't electro spark it by accident but that would be rare.

 

Alright..



Noid light shows good during crank on BOTH injector plugs. Power is 12V. All grounds seem to be good..



I've ruled out the injectors, the PFC and I *think* the harness... NOW WHAT THE HELL could it be?



I checked the CAS with the key in "on" 4V.. Is that right? Both of them show the same 4V.



Couple questions..



I used a multimeter on the injector plugs during crank... It was kinda choppy and I couldn't really figure out what the reading was.. I saw 10-12V, but not 12-0-12 like I thought I should..



Will location of grounds screw with it? There are 2 I'm confused about.. 1 is behid the UIM. Not the one that people usually replace (The one with the plastic plug) but the one like right above the bellhousing.. Does it go to the UIM, or the firewall? Or does it matter?



And the other one was originally for the negative battery terminal (I think) passenger side harness.. Thick black/yellow wire.. That can pretty much just go right?



Jesus I hate this crap!!

 

This may sound "stupid" but is the engine properly grounded? First engine I ever swapped had a really bad problem with starting. I had to ground the frame of the car to the alternator bracket for it to properly start.

 

It sounds like you don't have the engine grounded properly. The two main grounds are from the block to the frame and the UIM and the frame. I would add a few more becasue the rx7 is known for its poor grounding. (3000 rpm hesitation)



I don't know how much this matters, but what grounding the ECU? I know it is a long shot, but it is worth a shot.



A friend had his motor installed and the only ground he had hooked to the motor was the dinky one on the UIM, and it wouldn't run.



Here is a link to a good picture of all the grounds that "Grounding kits" add.









The thread is http://www.rx7club.com/showthread.php?s=&t...ighlight=ground



Good luck...