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Showing Visitor Messages 1 to 10 of 11
  1. Bastion90
    10-05-2016 08:12 AM - permalink
    Thank you Jason. I am using your instructions along with the Tmoss diagrams. You did an excellent job on them, since my wiring is different it leaves a couple of questions. You had a thick gray/yellow wire which runs to the O2 sensors at the EEC side. I see a small wire like that on one of the connectors, but not one like you show. Does that just need to link to the switched on power somewhere? Also my ends for the Ignition coil (engine bay) are not like what you and Martin show. I found another diagram that shows some Ign Coils having its own relay (which I do not have). Any help on what I should do? I will be doing the same as how you set yours up for relays. I found the EEC relay and the FP Relay. I will connect those at the EEC. Then I will run a yellow wire out to the fuse box linking them together with Pin 1. Any recommendation on the fusible link to use? Can I just tap in all the red wires to the EEC Relay/FP Relay/Pins 37/57 or do they need a separate power source? TY! Wayne
  2. MRM331
    10-04-2016 02:08 PM - permalink
    You are right, something is amiss with that diagram. The yellow should be hot at all times and the red/ltGreen is keyed. The fuel pump power should be hot at all times as well (as its labeled).

  3. Bastion90
    10-04-2016 08:05 AM - permalink
    Hey Jason, I was working on my wiring for my 5.0 swap and had a question for you. I am using a 1991 T-Bird wiring harness so its of course a little different from the Mustang diagram I have. My issue is looking at this diagram, it shows the YELLOW wire to be "Hot in Run or Start", then the RED/LG wire as being "Hot at all times". Is that backwards? I assumed the EEC #1 got full time power and the RED/LG going to the coil would be a switched on power. Thanks for your time

  4. MRM331
    06-13-2015 06:14 PM - permalink
    Hi Chris,
    Honestly I really don't know how Martin now has you wire up a V8. In the past he didn't even use a fuel pump relay, he would just jump the connection past the stock mazda relay with a switch on it. This totally bypassed the ecu and would burn up the switch if you didn't use a very high amp one. I integrate a new fuel pump relay into the harness and let the ford ecu control it. If you somehow confused your inputs for your fuel pump relay with the inputs for the ecu relay itself you could cause all types of issues.
    I'm coming up on summer vacation in a week which means my lead times drop from a few months to a few weeks. I have five orders in line right now but if you want to pull the harness and send it to me I'd be able to look at it within a month.
  5. barrattboy72
    06-11-2015 10:44 AM - permalink

    Please help! I wanted to have you do my harness but your lead times were too far out for me so I am struggling with my own.

    What I have is a A9L wired exactly per Martins manual in my 1990 Miata. The problem I am having is that when I connected the battery everything seemed to be working electrically (horn, lights, etc) but after about 10 minutes I smelled melting plastic with the key off. I immediately unplugged the battery and traced the smell. First it was the fuel pump jump under the driver dash. Second the fuel pump relay located by the EEC was hot to the touch. What am I doing wrong? If you wouldn't mind responding via email that would be awesome, I don't get on here very much.

    [email protected]

    I really appreciate your help and I will be purchasing a TPI heatsink kit in the near future.
  6. Gunpilot
    03-13-2015 07:53 AM - permalink
    Jason- I really don't want to reinvent the wheel, so do you have any pictures of the airbox for your intake? Where did you locate the calls and attachments to capture clean cool air?
  7. rowen210
    06-13-2014 12:38 PM - permalink
    Sending pm
  8. ooeclipse
    01-09-2014 07:23 PM - permalink
    sending pm
  9. fun02se
    12-19-2012 07:24 PM - permalink
    Hi Jason,
    Any chance you remember a post with info and/or schematic on the AC wiring?
    I have checked here and M.net and can't find it.
    Merry Christmas to you and family
  10. rookie
    04-05-2010 04:30 AM - permalink
    Jason, I have a couple of questions... First an update. Miata now out on the road. Logged 150 miles this weekend with no problems so far....Finished wiring in a relay to bring on the fans when the a/c compressor is running.. Works fine. Heres the question part.... I charged the a/c to the exact charge listed for the miata. It is a 134a system and converted the ford compressor to 134 with draining and adding pag oil. I no longer have a site glass on the dryer as the aftermarket one does not come with one so I am not sure if the charge remains the same with the ford compressor and the addition hoses added to mate the two systems together. The issue that I am having is that it will not pull below 50 degress. I am not getting any icing. Low side line nice and cool and sweating... Dont want to just add more gas as that can create more problems. Any info on the charge capcity will help... Also changing to the engine oil capicity with the modified oil pan from Martin...does it hold a full 5 quarts or do I need to adjust the oil capacity...

About Me

  • About MRM331
    Allentown, PA
    Miatas and big engines
    Elementary Teacher
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    On Road fun: 1994 Laguna Miata powered by a 5.4 Liter Ford Mustang engine-SOLD
    Off Road fun: 2015 Jeep Renegade powered by a 1.4 Turbo Fiat Abarth engine
    Next Victim: 1999 Triple Black Miata soon to be getting a GM LFX V6 or Honda J32a3

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