Mustang 5.0L EFI 10 Pin Connector Fix

How to perform the 10 pin connector fix.
This fast, free mod resolves a lot of the idle issues that Fox body owners have. It resolves a known issue with the wiring in these cars, and should be done on every single 5 liter Fox body.
Important note: The correct way to unplug these 10 pin connectors is to squeeze both clips IN, not spread them out like I did in this video. Either way works, but you're less likely to break them if you squeeze them both inward toward the connector at the same time, and then unplug the connector.

[@frankocasio8202]

excellent video

[@MrLocomechanic]

You split them because you’re supposed to push them in not pull them out 😂

[@MattSpinks]

Why is this making me uncomfortable...

[@dragradialperformance3540]

You're asking me? Man up and do this job, because every fox body needs it.

[@eddierodriguez2472]

i have read about this in several forums but no one to actually show the process..great job..

[@dragradialperformance3540]

Thank you! Check out part 2 as well.

[@nuebeats3655]

Connector push in not out

[@adventureofairjiggs8485]

Thank you .I'll let you know how it works for me?

[@roadrunner6961]

Thanks for the showing how to do this, I done everything on my 1986 5.0 5 speed and car runs good but sometimes just idles high and stays there , can shut it off and recrank it and idles fine, this is the last thing I think it could be. Great Video 👍

[@dragradialperformance3540]

Could be a misadjusted throttle stop screw. Warm the engine up fully, then unplug the IAC. If it doesn't drop in RPM, the idle stop screw is too high. It should be able to run with the IAC unplugged, but should be at a much lower RPM than you want. But still high enough to not stall. If it's not, adjust the throttle stop until the engine runs but barely. Then plug the IAC back in.

[@roadrunner6961]

@@dragradialperformance3540 Thanks for replying, and one other thing I forgot to tell you, is when it idles high I just looked at gauges and my temp gauge reads higher, same with temp gauge, and with fuel gauge. Thanks for replying I'm going to sub.👍

[@bchaveezy]

You press on the clips for the 10 pin connectors, you will surely break them if you try to pull them away to disconnect them.

[@dragradialperformance3540]

Yes, I misspoke. You squeeze them. It's the most awkward design ever. When they partially break, you have to get creative.

[@Lxmustang805]

Does this also help with cleaning codes .?? I have code 31 egr voltage low , also when I move the salt and pepper connectors my cars stumbles ..

[@Lxmustang805]

All my egr components have been replaced ,code still pops up.

[@Pontisteve]

@@Lxmustang805 If the EGR valve position sensor wires go thru the 10 pin connector, and they probably do, then yes an issue with the 10 pin connectors could cause EGR codes. It can't hurt to do this service and see if it fixes your EGR codes. And it certainly will help with your idle and stumbles.

[@PANTYEATR1]

hmmm...i know the SN95 doesn't have those connectors, but I'm wondering if i have similar connectors with that style of pins. i know the ABS and A/C connectors are somewhat similar, just not as big. good videos💪

[@Soundwaves4ever]

My 95gt 5.0ho is having random miss and drinking gas now ..... was getting around 20 mpg highway 17 town .. now I'm 15mpg high - 10mpg town ... all new ignition system besides lower distributor... also check +10 on crank and factory time ....... 71,000 miles garage kept 25years in Indiana, 0% rust ... it set almost 3years in a never moved. I Just got it a month ago and it's my first car in general (truck guy) I'm also running cool after draining antifreeze... tried 4 different 195temp and its opens at between o&r. Hasn't been middle of normal since ...

[@el_dela_guindaalex3254]

Would this be the cause of my 5.0 only running injector 1,2

[@dragradialperformance3540]

Only 2 out of 8 injectors are working? It's possible that this is the problem, but you need to check for injector pulse on the other 6 injectors. If you have injector pulse, then maybe the other 6 non-working injectors are clogged up and need to be ultrasonically cleaned, or replaced. If you don't have injector pulse on 6 injectors, it could be this 10 pin connector fix. It could also be that the plastic fingers that retain the injector control wires in the PCM harness connector are broken, and the injectors aren't actually plugged into the computer.

[@el_dela_guindaalex3254]

@@dragradialperformance3540 I did the test ended. I got scammed for a ecc and got a 2.3. at least I checked and fixed my harness though.

[@mikemarks1834]

Hey if you’re still out there just want to know what kind of cleaner would you clean the connectors with

[@dragradialperformance3540]

I just use an electrical parts contact cleaner from the parts store. I spray plenty in there and let it sit while I work on the contacts.

[@timsharpe2419]

I will try this tomorrow. Tnx

[@pugetlexus]

thanks for this video

[@DumbDuude1001]

Is this a thing with the 4.6 too? The hanging high idle that eventually drops is an issue im having with my 97.

[@dragradialperformance3540]

No, the 4.6L does not have these 10 pin connectors. If I were you, I would start by removing and cleaning your throttle body, and cleaning your IAC valve with carb cleaner and a tooth brush. Then I would check TPS signal voltage with a scantool or a voltmeter. You should see around .96 to 1.02 volts, with about a volt being ideal at idle. If you see a good bit higher voltage than that, then either someone has turned your idle stop screw up inappropriately, or your throttle cable is binding. Temporarily remove the throttle cable from the throttle body to see if that resolves the issue and puts TPS voltage back down to a volt where it belongs. If it does not, and TPS voltage is higher than say 1.03 volts, then your stop screw is set too high. The easy way to fix that would be to just turn the throttle stop screw down until you have 1.00 volts on your TPS signal wire or TPSv on the scantool. You should also check for obvious vacuum leaks. Look hard at the large rubber elbow near the upper intake. They like to rot out, which usually causes a low idle or stalling. But someone may have raised the idle stop screw to "fix" another issue.

[@DumbDuude1001]

@@dragradialperformance3540 Wow, thanks for all of that. I have a few days off of work here, so i should be able to try this. Big ups yourself!

[@davidm3302]

Just curious I got a 93 f150 lightning that throws no codes but gets some quirky idle and drivability issues do those vehicles have those connectors?

[@dragradialperformance3540]

I don't recall, but I don't think so. One look at the wiring harness will tell you. If they're there, they may be under that cover plate on the intake. On a truck that age, you're going to want to pull the PCM out, remove cover, and inspect the 2 or 3 capacitors very carefully for signs of leakage of electrolyte. In fact, it's of the age where they should be replaced anyway, even if by some miracle they are not leaking yet. When these capacitors go bad, the vehicle can do anything from run funny to not run at all. You should also make sure you don't have any vacuum leaks. A mechanic's smoke machine is the best tool for this.

[@davidm3302]

Thanks for the reply I’ve checked for vacuum leaks I sprayed around the connection with carb cleaner no change in idle. I will look into the computer definitely. On the lightning website some guys mentioned take a look at the 60 pin in the harness

[@dragradialperformance3540]

@@davidm3302 the EEC-IV computer has 60 pins, so they're talking about the PCM connector. It is possible for there to be corrosion or damage there, and it can't hurt to give it a visual inspection while you're removing the PCM. But the red plastic connector lock that retains all the wires in their correct holes fairly well obstructs the view. You can view the pins on the PCM itself and see if there are any green crusties on them once the connector is unbolted. You can also test fuel pressure. Should be 39.15 PSI +/- 1 PSI with the engine running and the fuel pressure regulator vacuum line temporarily removed. Timing should be 10 BTDC with SPOUT connector temporarily removed. You can clean the thottle body with carb cleaner and a tooth brush. And inspect all vacuum lines, emissions hoses, etc.

[@davidm3302]

Thanks for the help I’ll take a look at that stuff this weekend. Not going to let this thing beat me lol

[@robertrivasarroyo1174]

Good stuff!!!