Resolved 87' GT hatch project

Well I cracked open the ecu to give it a look for myself, best I can tell it is a VM1 ecu and it is original to the car. The inside looks flawless and the caps do not appear leaking or bulging I can't seem to find any good information on the speed density ecu's.

foxecu1.webp
foxecu2.webp

foxecu3.webp
 
Well I cracked open the ecu to give it a look for myself, best I can tell it is a VM1 ecu and it is original to the car. The inside looks flawless and the caps do not appear leaking or bulging I can't seem to find any good information on the speed density ecu's.

foxecu1.webp
foxecu2.webp

foxecu3.webp
A couple of thoughts…

If you plan any engine upgrades, you may want to consider upgrading to MAF. Of course, an aftermarket system will negate that.

And I was surprised by what ECUExchange found and fixed on my MAF ECU that was considerably newer than the stock SD ECU on my ‘86.

Bill
 
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A couple of thoughts…

If you plan any engine upgrades, you may want to consider upgrading to MAF. Of course, an aftermarket system will negate that.

And I was surprised by what ECUExchange found and fixed on my MAF ECU that was considerably newer than the stock SD ECU on my ‘86.

Bill
Yeah I was thinking of going to an aftermarket setup, but I'd like to get the car running right on it's original equipment before I do that. I'll be sending it into ecuexchange soon.
 
It's been a few months, slow progress but I have been driving it a lot too!

Today I installed a new SVE aluminum radiator from LMR. Before I was having cooling issues, temps would constantly creep and hover around 220 which I didn't like. Also installed a new 180 thermostat and removed the old A/C condenser as it was doing nothing, while doing the test drive after the install I never saw the temp hit over 200 at all! I will need a new fan shroud as the original one is broken and comes pretty damn close to the fan at the bottom.

Although in doing so, I had to move the distributor as I had no access to the right water pump housing bolt from any angle but where the distributor was, I marked its location but I think the timing is screwed up now. It feels down on power and above 4000~ rpm it completely falls on it's face I plan to get a timing this week to check it out.

Next on the install list is a new brake master and all new brake hoses, the master is leaking and the hoses are likely original and in terrible shape, probably explains why the pedal goes 1/2 of the way down and doesn't do much.
 

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Went through and did plugs and wires the firing order was correct I believe they just didn't clock the distributor right, car ran and drove great no more stumble above 4000!

Installed a MS2PNP ecu on Friday and it still isn't quite running right but I believe I've narrowed it down 100% to a bad TPS, I have went through checking the resistance at a bunch of connection points after reading through other threads and I can't get the TPS voltage above 0.5v. I have tried to calibrate the TPS multiple times in tuner studio and it wont go above 180 in tuner studio whether I'm on the pedal or not, after looking at the TPS closely it appears to be an original FOMOCO no doubt original to the car. The IAC was also giving me issues and did not seem to be responding at all, I checked the wires for that and all checks out, I removed the valve and supplied a direct 12v to it and it at first it did nothing, after a few more tries it seemed to start working and when I reinstalled it the car finally would high idle when it was cold and the idle drops as it should now which it has never done before since I've owned it!

I did order a new IAC just in case and I ordered a new FOMOCO TPS which I will install once they come in, while attempting to test drive the car the TPS seemed to work for a few seconds and while accelerating in second gear it felt like it had 100 more hp than it ever had, I cannot wait to test and tune more
 
TPS was 100% bad! new TPS is working fantastic also went and did the IAC valve and a fuel filter as the old one was very crusty and didn't look great.

After dinking around messing with it I have it to a point where it is now drivable. There is still TONS of tuning left to do but compared to before with the old ecu the car probably has 50 more horsepower than it did before. I am very pleased with the results so far!

Just need to install a new drivers outer door handle as it exploded on me leaving work a while back and do some general cleaning, street machine nationals is in a week and I'm not missing that! I may also put it on the dyno there to see what it puts down to the rear wheels,
 
Well it's been a few months, winter is around the corner and the fox is in storage for the winter.

My car has always stunk of mice since I had gotten it, I have seen four in the car so I decided I am pulling the interior first and foremost. Today I pulled the dash out of the car as well as the dash wiring harness as it needs to be replaced, so many broken and damaged wires. I am also planning on replacing the column and plenty of other parts to put the interior back together as it should be! Surprisingly the dash wasn't too hard to remove not real fun doing it alone but definitely possible with one person.

I'd like to have the interior factory but with all new (used ) components to replace all the broken :poo: on mine, not having HVAC of any sort drives me insane! anyone happen to know where I could find a dash harness for an 87' GT? :shrug:

fox dash out.webp
 
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www.car-part.com

87 or 88 will work. Pretty sure you can use a 4 cylinder or V8 harness. My require some repinning on the instrument cluster?

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I was talking with my coworkers and they suggested this website! I’ve never heard of it but it seems pretty damn nice.

I figured just about any harness between an 87-89 would work. I’ll do some digging tonight to find the parts I need! I am scared to put the dash back in, lot easier to pull it out than to put it back in :notnice:
 
Good news! I had a think about my harness situation and realized that I technically don’t need one.

Last night (technically this AM lol) I went through the harness and removed all the unnecessary radio stuff from the harness leaving me with just the speakers, radio power/ground/illumination wiring which is exactly what I need.

I also went through and fixed the clutch safety switch wiring. I found the switch to have been bypassed with a jumper wire which I removed I also found a bad switch on the pedal assembly itself.

Next step I want to complete is to replace the heater box as the mode doors on mine don’t feel great and the vacuum actuators look terrible.
 
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Well long time coming, car is allllllmost ready for the spring. If all goes right I should be able to drive this weekend! My dash, steering column, and most of the interior bits are all back together. I have started the car a few times and tested with no major issues. I now have a fully working HVAC system minus the A/C before there was zero air flow out of any of the vents.

The last few things I need to do are reinstall my oil tube extension (drilled and tapped for a mechanical gauge), reconnect my steering shaft to the rack, and do an oil change. I would also like to change the fluid in the transmission, and preform a tire rotation but it's not a huge concern right now.

I was scrolling through other forums trying to find how to extend the slip shaft in the column itself, I think the trick will be a slide hammer, I just need the shaft out about 2-3 inches. I have a gt40 intake I am going to swap within the next few weeks here and I plan on doing a new exhaust with shorty headers.

Last time I started the car I noticed there was zero vacuum boost on the brakes, it is a brand new booster and the MC is less than year old. I am going to hope this is caused by the pushrod length not being correct? not quite sure.
 
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