Engine 85 cfi issues

1TDUBB1

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Apr 17, 2018
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I just picked up an 85 with an erratic idle issue. It pretty much always idled at a little under 1k (which is to high to begin with). Then every once in a while it would jump up close to 2k for between 10 - 40 seconds and there never seemed to be any rime or reason why it went up or down.

So I played with the chock one day, and got it idling at a perfect 800 in neutral and about 650 in gear and it doesn't jump up anymore either. Now according to what I seen and read, the wire to the choke should be down towards the motor, but mines more on the right side towards the front of the car. So it's about a 1/4 turn off from what everyone says it should be, but :poo: if it runs better this way, I say their wrong, not me.

But we'll see what happens in the winter, when the choke is actually needed.
 
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1TDUBB1: your dealing with a carb, so your problem will require a different process but you likely also have a vacuum leak and/or a mis adjusted carb.

It's the 85 convertible, which got the first EFI throttle body, the 85 coupe still used the 4 barrel Holly.

Which is very frustrating, this is the 3rd play vehicle I've bought that just happens to be the one year the Manufacturer tried something new, so finding parts and service advice is hard.

So, if anyone runs across a good deal on an 85 Convertible GT........RUNNNNNNN!!!!!!!

If your bored and want to have some fun, go look for parts or how to's for an 85 Mustang. Specifically an 8.8 rear end swap or anything to do with the intake, throttle body, or air filter. And "How To's" , they just flat out don't exist!

That's alright though, I like doing things the hard way, and my Man Card is strong, cause I never ask for directions and always throw away the instructions......and then dig them out of the trash later, but don't tel anyone
 
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Don't know, I haven't dug into that, but I did have it checked at a shop last weekend, and they said there were no vacuum leaks, the compression test was pretty good for something with 109Kmiles, and the timing was good. He said the technician did play with the choke and idle a little, but he felt like he ended up right back where I had everything set.

But here's the kicker on that waist of $95, he then told me about the coolant leak on the T where the heater core was bypassed. He said it would only be $35 to replace the T and 3 hose clamps, I laughed, then he proceeded to inform me that my biggest issue was that the right Valve cover gasket was also leaking coolant and that was going to be a harder fix so it'll be $377 for the labor and $65 for the gasket. So, I proceeded to laugh, even harder this time and said give me my keys please, your a crook.

Then when I started my car, the idle was worse than it was before I fixed it. So here I am in the Lambs parking lot readjusting the choke back to where I had it and the tech came out trying to explain what he did. I stopped him and asked " Is there oil in my coolant", no, "how about coolant in my oil" , no. "OK I've heard enough from you guys"

That brought me here. But to your point, I feel like my next move is plugs and wires, but your right , I might go all out with a distributor and ignition coil.
 
Here is a small amount on what came with what in '85. And it appears that there was an ecm on the cfi cars. Look for a data link in the area of the master cylinder.

underhoodpictures007-01-jpg.jpg
 
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I've been spending a lot of time under the hood this week(which my wife LOVES by the way), mainly just cleaning and rerouting things to got it nice and organized (It was a mess), I'll have to post a pick later. Anyway I found that connector and am planning on going up to Advanced Auto and having them check it out.

But I found a few more spliced connectors one of them being the green wire to the ignition coil was cut about a half inch from the connector and they used one of those lock wire connectors.

So I ordered a new pig tail for that and the A/C.

As for the idling, I finaly figured out the heater hose routing (for a CFI engine) and part of that is a EGR heat sensor that's in the core supply line. That senor is for the EGR to make idle adjustments. It purse like a kitten now.

So I'm going to take a little brake and try to restore my wifes faith that I do actually care more about her than "that damn car" as she calls it. LOL
 
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I've been spending a lot of time under the hood this week(which my wife LOVES by the way), mainly just cleaning and rerouting things to got it nice and organized (It was a mess), I'll have to post a pick later. Anyway I found that connector and am planning on going up to Advanced Auto and having them check it out.

So I'm going to take a little brake and try to restore my wifes faith that I do actually care more about her than "that damn car" as she calls it. LOL
Go buy her a mushy card and flowers or a balloon. Neither one is fattening or expensive...
 
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