1986 mustang shutting off, please help car is not driveable!!

[qikgts]

Just cause we're having such fun in here... GUFB Strat doc...

http://www.amopower.com/files/GFUB%20family.pdf

[crazyfox]

holy moly lot of info there. lol

[dynodon64]

Just breezed through this whole post again, I see the only item that wasn't changed is the PIP sensor in the distributor. I know you had the same problem with the aftermarket distributor too, but you may have had a TFI issue when it was in. One of two things to try now. First check the PIP sensor and make sure there aren't any metal filings stuck to the magnet, and also look at the stator ring that the rotor sets on for metal filings as well. Then if that looks good, maybe try the new distributor again.

Does any of the dash instruments die when the engine shuts off, besides the tach ?

[crazyfox]

the new mallory distributor has been in there since posting # 1. I never switched back to my stock one.

only the tach drops, other guages stay

[crazyfox]

Found the fuel pump relay. Somebody had installed a new carpet and buried it under the carpet. I cut a slit in the carpet and brought the bracket and relay to the topside of the carpet under the driver's seat.
So, I wanted to mimic the fuel pump power getting interupted to see if it behaved like my normal symptoms when the engine shuts off. I pulled the fuel pump relay connector out of the fuel pump relay with the engine running and the motor stumbled and died with symptoms more consistent to running out of fuel (as opposed to the quick manner in which it usually dies.)
I also wanted to see how killing the engine that way affected the restart operation. (remember that normally when the engine dies I have to cycle the key off and then on. In this case I plugged the fuel pump relay back in and restarted the engine WITHOUT having to cycle the key) also of interest was when I plugged the fuel pump relay back in with the key on (not cycled back to off and the on) the fuel pump relay did not click and the fuel pump didn't prime which makes sense because I think the key would need to be cycled off and on for the fuel pump prime to happen).

so, I feel pretty confident this is not fuel related so I guess we're back to the spark side of things again. yay!

I don't know if my earlier test ride with the fuel pressure regulator vacuum unplugged and the engine not dying was just a fluke or what. I did about 15 miles that way both interstate and back roads. I do have the miss though when i give it gas from about 2300 rpm. It seems like it loses spark for an instant but it doesn't show on the tach. (only shows on tach when engine shuts down)
I rambled on long enough, open to thoughts now

[crazyfox]

ok, on we go, so tonight as I was running the car in the garage it went into some crazy mode. It started running very rough/misfiring and shaking. In addition the tachometer dropped to zero while the car was running. If I sped the engine up, the tach would register and the engine would smooth out but bring it back to idle and the tach dropped and was running real rough (almost like it wanted to cut out but didn't go all the way to shut down). when it did finally shut off I was able to restart it WITHOUT having to cycle the key off and on like I have had to do every time before. I noticed a relay near the battery was super hot and when I unplugged it didn't seem to affect anything (looks like it has something to do with a/c system (which has been removed from my car). I wonder if I should just leave that relay unplugged?? There is definitely power going to the relay because I can hear it click on and off when I plug the connector into it. (think it is a wide open throttle cutout relay??)
anyway, I let the car sit for about 5 minutes and then restarted it and now it is running in it's normal mode again,. I didn't let it run to the point of the engine dying again though so I don't know if the above condition will show itself again)

copy link to a video I made tonight of what was going on when it was running super rough and misfiring and the tach not reading

https://youtu.be/BuW4IXdjhbQ

[crazyfox]

car sat overnight, won't start now. just cranks and cranks.


I tested for 12 key in run at terminal 3 of the module harness connector and i have 12v. I tested coil voltage and i have 12 v key in run.
i tested pin 4 of the module harness connector and i have 12v when cranking.
I took a video of me using the module and coil tester if you want to check it out.
I tested a previous motorcraft module and it tests bad (module test light comes on and stays on when tested.) (it's supposed to flash once and stop)(tester instructions says that means module is shorted)


the current module isn't lighting the tester light at all (tester instructions say that means that the module is open)
I have one more new module that hasn't been put on the car but I am hesitant to try it because I am not sure if something is making these go bad.


check out link to the video

https://youtu.be/PYT0c70YRLU

[crazyfox]

ok, so I put a used module (actually the one that fiirst gave me these problems before I bought the motorcraft module (that is now shorted).
started right up. I guess I'll take it for a drive. I don't completely trust this module as it was the first one to act up on me. I am hesitant to install the brand new module I have on me.
I wound up purchasing a module relocation kit that uses a heat sink. I'm at a crossroads, part of me says install the relocation kit and put the brand new sensor in the relocated heat sink and press on (the part of me that hesitates doing this is I am not sure if something is making these modules go bad. I don't know if I should buy another motorcraft module to install in that heat sink or use this new duracraft module I have. I'd rather only install a module once onto the heat sink because I don't want to use up the special heat paste they included with the relocation bracket (they claim it's better than dieelectric grease or the radio shack heat sink compound. your thoughts are always welcome so let me know.
ps. (as of yesterday I now have a reman eec in the car (same part number as the original one I removed.

another video of me changing the module and the car finally starting up

https://youtu.be/PYT0c70YRLU

[dynodon64]

So is it running right or ruff, and is it still dying?

[crazyfox]

seems to be running ok (still have a rolling idle but that always seems to be there. Didn't run long enough yet to see if its going to shut off. I am installing a module relocation kit tonight to move the module to the inner fender. I will then report back after I test drive it (hopefully tomorrow)

[gmatt]

In the interest of K.I.S.S and the fact that just about every possibility has been covered, I'm going to offer this: (If you haven't already done this) are all of your ground connections clean and tight? Engine, chassis ground straps in good condition? What condition is the battery? I had a car once that would intermittantly die and immediately restart as if nothing was wrong. Very frustrating. Turned out to be a loose connection on the alternator charge cable. Sometimes when we work on our cars little details like tightening everything that we loosened can get overlooked. Good luck, we're rootin' for ya.

[crazyfox]

grounds are fine, I think this time it is pretty clear that the module is to blame. If you've watched the videos you would see what I am talking about. The only thing that got the engine running again was changing the module. I think my tach acting up was due to the supply voltage to the coil not correct (in the video marked mustang saga).
I'm rootin for me too!!!

[dynodon64]

One more thing that is rare, but happens, is disconnect the alternator and run it on just the battery. I've seen a diode go bad and cause issues with the electronics. There are 6 diodes in an alternator that convert the AC output into a rippled DC. You may not see a problem because the battery will absorb some of it, but the electronics will detect it.

Just something to try if it is still dies.

[crazyfox]

Maybe it's just my meter but earlier today when I checked the voltage at my battery with the engine running (before you asked me to check this) my meter flashed 19.5v or so for a split second then showed 14v running. each time i removed and placed my meter's lead on the battery post I saw that 19v flash for a second. also saw that when checking voltage at the ignition coil. I had asked someone about that and they thought maybe my meter was too sensitive. I will try another meter tomorrow and also try the alternator unplugged thing, maybe we are on to something. (I certainly don't want to ruin another module or worse.)

[crazyfox]

I tried another meter and it doesn't show that 19v before it shows 12v. So maybe that other guy was right about my meter being the reason why I got that reading. I will try the alternator unplugged thing tomorrow regardless after I finish the remote mount module setup

[crazyfox]

just got back from a 60 mile trip in upper 80s temps, highway and non highway driving.
didn't die on me. I will take it out tonight and see how it does.
I do still have a little hesitation when I open the throttle quickly mostly when changing gears. I'm wondering if my timing being set at 14 degrees could be causing that? I will play with that tonight also
I did put a new hayden clutch fan (non heavy duty) on the car (think that could be causing that little hesitation (like if it is not releasing the fan clutch)

[crazyfox]

update, in an effort to try to get rid of the hesitation I put my stock ford distributor back in (in place of the mallory) and took it for a drive. Right away it ran better and smoother and had a noticeable increase in power. also the hesitation went away.
I then looked a little closer at the mallory distributor and realized I didn't have it set up correctly. (on the mallory #1 cylinder is just to the right of the hold down screw (not 2 to the right of the hold down screw (or clip in ford's case)
soooo, when I put the mallory distributor in I actually had the rotor pointing at # 8 not # 1 !!!!
I realized #1 on the mallory was in a different spot by spotting an engraved 1 on the underside of the distributor bowl (wow,, you'd think they make that clear in the instructions!!!!)
so I put the mallory back in (timed correctly this time, took it for a drive and it performed just like the factory one (better idle, good power and no hesitation)

So, throughout this saga I am wondering if anyone thinks having the distributor in wrong was causing the modules to get too hot and fail?? like maybe the ignition system was working too hard or something.
Thoughts????

[grabbergreen84]

Maybe that's what's wrong with fgross2006's Mustang. His car keeps frying TFIs too.

[crazyfox]

does he have the same distributor I have?

[crazyfox]

3 successful days now, 90 degree temperatures, over 120 miles. knocking on every piece of wood I can find !

[JTurbo]

Congrats, I've been watching this thread, I didn't have anything to contribute but glad so far, so good....

[crazyfox]

So far so good, I just wanted to thank everyone who helped me out with this. This is a great resource and I am very thankful for everyone's help.

[arjupraja143]

Just pull the turn off the colum and begin the vehicle having a screwdriver. Whether it stays running you've found the issue.

[Haystack]

Im glad ya got it fixed. Intermittent issues are the worst. At least when it doesnt start, there are things to check.

On my 88xr7 my fuel pump kept intermittently dying on me. Couldnt find anything wrong and even swapped the fuel pump trying to figure it out. When I bought the car, the fuel tank straps were rusted through and the fuel pump was ghetto rigged with a switch right off the battery with a bunch of random wire holding up the smashed gas tank. Looked like it fell out while.driving on the last guy.
I spliced in a new power wire and hooked everything up properly when I bought the car but it still would randomly not start the pump. After dropping the tank for the 4th or 5th time I decided it had to be a bad splice. I pulled all the wiring up through to the trunk and ripped off all of the tape. About 6" after I had spliced in the new wire, there was a section about a foot long with about 10 breaks in the wire that the last guy twisted together and then taped up. It's been okay since, but drove me nuts forever.

[cb84capri]

Just pull the turn off the colum and begin the vehicle having a screwdriver. Whether it stays running you've found the issue.

Am I doing this right?



Cale