1986 Mustang GT car cannot idle and runs at 200rpm for a couple seconds.

Welp, I am back on here asking for more help on my first project foxbody.

I have this 86 5.0 5 speed SD and currently will NOT run at all. It used to run perfectly before these issues, until one incident. The car stalled while trying to take off in 3rd gear and when the car started again, it was running at 2k rpm without going down no matter what. After 2 days of sitting i took apart the upper intake and checked for any vacuum leaks and cleaned the salt/pepper shaker connectors. When put together, the car was extremely choppy and wouldnt run without running extremely lean and without making a major vacuum leak. Im currently 8 months into it not running and im on my last straw with the car.

So far, I have done a complete vacuum leak check with a smoke machine with no signs of a vacuum leak, I cleaned the 10 pin connectors, I adjusted the timing both ways, I replaced the fuel pressure regulator, I changed spark plugs, I changed spark cables and cap, I have changed upper intake gaskets, and I cleaned the current IAC and ran a different IAC off of a running 302. Ill update this if I can think of anything else I did over the past 8 months that I forgot about. Im also starting to get a fuel smell in my oil if that adds any merit.

So, what do you guys think the next step is? Im not sure if it could be a computer issue, timing, or fuel issue. I think I might clean the injectors and if that doesnt do it Ill figure out how to see if the computer is good. If anyone would like to add anything or might know whats wrong please reply. Im at my wits end with this car.
 
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Welp, I am back on here asking for more help on my first project foxbody.

I have this 86 5.0 5 speed SD and currently will NOT run at all. It used to run perfectly before these issues, until one incident. The car stalled while trying to take off in 3rd gear and when the car started again, it was running at 2k rpm without going down no matter what. After 2 days of sitting i took apart the upper intake and checked for any vacuum leaks and cleaned the salt/pepper shaker connectors. When put together, the car was extremely choppy and wouldnt run without running extremely lean and without making a major vacuum leak. Im currently 8 months into it not running and im on my last straw with the car.

So far, I have done a complete vacuum leak check with a smoke machine with no signs of a vacuum leak, I cleaned the 10 pin connectors, I adjusted the timing both ways, I replaced the fuel pressure regulator, I changed spark plugs, I changed spark cables and cap, I have changed upper intake gaskets, and I cleaned the current IAC and ran a different IAC off of a running 302. Ill update this if I can think of anything else I did over the past 8 months that I forgot about. Im also starting to get a fuel smell in my oil if that adds any merit.

So, what do you guys think the next step is? Im not sure if it could be a computer issue, timing, or fuel issue. I think I might clean the injectors and if that doesnt do it Ill figure out how to see if the computer is good. If anyone would like to add anything or might know whats wrong please reply. Im at my wits end with this car.
I don’t know about that 3rd gear thing. It shouldn’t have anything to do with the problem.
Sounds like you’ve done a lot of normal things.
Is the ECU original? That’s a 38 year old computer, most are ready to crap out I’d pull it and take a look inside at the capacitor’s (3). A bad ECU causes havoc with the fuel injection. If you see anything suspicious, send it to EXUEXCHANGE for repair. (Doesn’t cost much)
 
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I don’t know about that 3rd gear thing. It shouldn’t have anything to do with the problem.
Sounds like you’ve done a lot of normal things.
Is the ECU original? That’s a 38 year old computer, most are ready to crap out I’d pull it and take a look inside at the capacitor’s (3). A bad ECU causes havoc with the fuel injection. If you see anything suspicious, send it to EXUEXCHANGE for repair. (Doesn’t cost much)
Awesome thanks for this. Ill take a look at the computer and notice any bad capacitors and see if I can do them myself or buy the repair on ecuexchange
 
The issue with swap'n ECUs is you could trash the test unit, chafed wires may not short out right away and you think that was the problem only to have the problem come back later and effecting that computer.
Get that one looked at. It may have a burnt ground trace
It's old
Like me.
well maybe not that old but you get the picture.
 
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well maybe not that old but you get the picture.


Yup

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:jester: