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Discussion Starter · #1 ·
Seems as though I have 2 (possibly more) separate (I think) issues with my '88.

1. Having a problem with overheating. Was watching the fan and it never came on. Fan is brand new. As a result, anytime I'm stationary for very long the temperature creeps up. Also, strangely enough, in my morning commute to work (about half freeway - roughly 15 minutes total) the car isn't warm enough for the heater to blow air until I actually get to my job (not much help). Any ideas? I was thinking a stuck open thermostat for the too cold part, but not sure what the hell's wrong with my fan.

2. My car has a really rough idle lately. When started cold, it stays around 1200-1400rpms and doesn't slow down til it's warm (then around 800-900). Every now and then, if and when it drops below 700, it sputters, then corrects itself after a bit. And today, after it had overheated (not sure if related) it sounded like someone was blowing though closed lips and making that sputtering sound all kids do. Any ideas?

Thanks, guys!
 

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Address the cooling system first. It'll run rich at higher rpms if it thinks the motor is still cold.

Get a Ford thermostat, and check relays and fuses and such for the fan. Report back with results and we'll take it from there.

Maybe block off part of the radiator with cardboard or something to restrict cooling so you have heat to work?
 

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fuses and relays and typically located under the cluster on the driverside of the dash... pull the panel off and u should see em.... not 100 percent sure if the relays are there never had to change any before...
 

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Discussion Starter · #8 ·
Chilton and Haynes actually both had me looking in the wrong place. Found it after spending a couple combined hours searching the internet for a relevant post. Eventually found a great diagram and discovered my problem:


Turns out the previous owners had a decent sized electrical fire and didn't tell me. On closer inspection, the vast majority of the wiring has been replaced and quite a few places have been repainted.

Now I just have to get my vacuum up to par..
 

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Discussion Starter · #13 ·
More excitement. Turns out the wiring harness is from an 89' (mine's an 88') and there are some subtle differences which make it not work quite right. As a result, my car isn't up to par on vacuum because it's not working properly as a result of the electricity. It's also the reason the radiator fan isn't turning on. So, I'm wiring a manual switch in for the radiator. Is there anything cheap I can do for the vacuum to make it produce more vacuum? I'm just trying to get this car up to spec to sell it. I DO have access to a '88 wiring harness, but I don't think I can afford to have someone install it. (How much would it be?)
 

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six shooter
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I'd look into getting a proper EVTM for your car.

Aside from that, these cars are old and going through the entire vacuum system will lead you to bad hoses and cracked plastic, or missing things in general. I'm working through the same thing on my car, which is original.

If you have a day or two, just to the harness yourself. Figure out where all the ends go, and have to feed through, label them and switch everything out. It's more of an annoyance than a difficulty.
 

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Discussion Starter · #15 ·
I'd look into getting a proper EVTM for your car.

Aside from that, these cars are old and going through the entire vacuum system will lead you to bad hoses and cracked plastic, or missing things in general. I'm working through the same thing on my car, which is original.

If you have a day or two, just to the harness yourself. Figure out where all the ends go, and have to feed through, label them and switch everything out. It's more of an annoyance than a difficulty.
Yeah, the guy that was helping me found several vacuum leaks, but they should be all gone. Problem now is that it doesn't think it needs vacuum so it isn't giving me any. Where can I get a EVTM? Do I have to buy online?
 

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six shooter
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I got one for my Ranger on ebay. Might be harder to find for our older cars. I doubt the Chilton/Haynes are specific enough to be of much help. If I had one, I'd go make some good scans of it and post it online, but that's just me.

I found a vacuum leak somewhere under the passenger floor pan when I had my car up on stands. I had no idea there was a tube running back to the rear from there. Didn't feel like checking what it was, just did the hose when I saw it and got it over with. So you could still have several leaks.

Did you reset the ECU (unhook the battery) after you did all that work?
 
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