Electrical Question-Please help!

[sflrainmaker01]

I am testing my old 5.0 Mustang coil. It is a MSD Blaster TFI coil. I just finished "bench" testing it. If my readings are correct, the Primary coil ohms read 0.7 which is close to spec (0.68). However, the Secondary coil ohms read 3.14k and spec is 4.8k. Does that read like a BAD coil?

FYI, last night, my Mustang 5.0 just died at a stop light. It would crank fine, but not start. According to the FP gauge, there is fuel pressure. This morning, I tried to start it and it fired, but sounded like it was running on 4cyl or less. So, I have narrowed it down to the distributor or my coil. The distributor is a reman one that is a couple months old with maybe 200 miles on it. The coil is probably 15 years old but maybe 2000 miles on it.

Thanks for looking.

[RF Overlord]

Low secondary reading sounds like a short in the windings.

[fastblackmerc]

I'd replace the coil.

[sflrainmaker01]

Thanks guys! :) I, also, just talked to MSD. They told me to ship it back and they would send me a new one! :banana: No drop toppin' for me for a couple weeks though... :bigcry:

[ctrlraven]

What amp alternator are you running? Have you upgraded any power/ground cables?

[martyo]

My bet is in the cheap aftermarket distributor. When the car dies check the coil at that point. Place power to the power side of the coil then ground it quickly to see if it sparks.

[sflrainmaker01]

What amp alternator are you running? Have you upgraded any power/ground cables?

Stock alternator-recently replaced. But, the battery and power to everything is strong. No problem turning over the engine.


My bet is in the cheap aftermarket distributor. When the car dies check the coil at that point. Place power to the power side of the coil then ground it quickly to see if it sparks.

I just bought a cheap OEM style coil while I wait for a new one to come from MSD for free. Couldn't wait for two weeks. The spark seems stronger, but still only runs on a couple (?) cylinders. Keep in mind, everything is pretty much new in this car (engine, trans, clutch, rear, exhaust, fuel tank & pump & filter and more. There are only a couple sensors I haven't replaced like the ACT, ECT and O2 sensors.

The distributor came with a "new" TFI module that I installed per instructions. That leaves me wondering about the PIP sensor and TFI module. I heard these reman distributors can be junk, despite the lifetime warranty.

Would it be a worthy investment to just buy a NEW billet OEM type of distributor so I hopefully get new parts this time? If so, what brands are the best? I have seen MSD, Summit, Mallory (although I got two of their fuel pumps and they both were defective) or Accel.

[ctrlraven]

Turning over isn't what I am getting to, it's when the car is running.

The stock 2G 95 amp alternator is okay for a completely bone stock car but once you start adding stuff it's wise to upgrade to a 3G 130 amp unit. The stock one at idle is only turning over about 15 amps output and 75 amps at 2k rpms. When adding a high-output ignition system it's recommended to upgrade the alternator and charge/ground wires. It's only a benefit type of thing. http://www.latemodelrestoration.com/item/SVE-17046K2/Mustang-SVE-130-Amp-Alternator-Upgrade-87-93-50L

I'm running an upgraded distributor, PD dyna-mod module, screamin' demon coil, and MSD 6AL. Saw and felt increase after doing the 3G alternator and complete wire upgrade.

[martyo]

Stock alternator-recently replaced. But, the battery and power to everything is strong. No problem turning over the engine.



I just bought a cheap OEM style coil while I wait for a new one to come from MSD for free. Couldn't wait for two weeks. The spark seems stronger, but still only runs on a couple (?) cylinders. Keep in mind, everything is pretty much new in this car (engine, trans, clutch, rear, exhaust, fuel tank & pump & filter and more. There are only a couple sensors I haven't replaced like the ACT, ECT and O2 sensors.

The distributor came with a "new" TFI module that I installed per instructions. That leaves me wondering about the PIP sensor and TFI module. I heard these reman distributors can be junk, despite the lifetime warranty.

Would it be a worthy investment to just buy a NEW billet OEM type of distributor so I hopefully get new parts this time? If so, what brands are the best? I have seen MSD, Summit, Mallory (although I got two of their fuel pumps and they both were defective) or Accel.

Do not use cheap parts. They cause premature graying or hair loss.

Get yourself a stock Motorcraft distributor.

[sflrainmaker01]

Turning over isn't what I am getting to, it's when the car is running.

The stock 2G 95 amp alternator is okay for a completely bone stock car but once you start adding stuff it's wise to upgrade to a 3G 130 amp unit. The stock one at idle is only turning over about 15 amps output and 75 amps at 2k rpms. When adding a high-output ignition system it's recommended to upgrade the alternator and charge/ground wires. It's only a benefit type of thing. http://www.latemodelrestoration.com/item/SVE-17046K2/Mustang-SVE-130-Amp-Alternator-Upgrade-87-93-50L

I'm running an upgraded distributor, PD dyna-mod module, screamin' demon coil, and MSD 6AL. Saw and felt increase after doing the 3G alternator and complete wire upgrade.

Oh. I didn't know that! Thanks for the heads up!


Do not use cheap parts. They cause premature graying or hair loss.

Get yourself a stock Motorcraft distributor.

Ok. I'll see if I can locate one.

Thanks (as always) for the input! :beer:

[martyo]

Ok. I'll see if I can locate one.


That should be easy.

[sflrainmaker01]

That should be easy.

All I can seem to find is reman or new "billet" aftermarket stuff. The OEM Motorcraft one seems to be discontinued, which brings me back to the last paragraph in post #7. I'm leaning towards a MSD Billet one, assuming I can return the POS one in the car now (lifetime warranty) and get a store credit since it's only been in there since May.

[ctrlraven]

I use a Performance Distributors Hot Forged Aluminum unit, has been working fine for me.
http://www.latemodelrestoration.com/item/PDI-18457/1986-93-Mustang-50L-Billet-Distributor

[sflrainmaker01]

I use a Performance Distributors Hot Forged Aluminum unit, has been working fine for me.
http://www.latemodelrestoration.com/item/PDI-18457/1986-93-Mustang-50L-Billet-Distributor

Thanks man! That looks just like the MSD one for $20 less! Summit has one just like that for the same price.

Is your Mustang stock?

[ctrlraven]

Thanks man! That looks just like the MSD one for $20 less! Summit has one just like that for the same price.

Is your Mustang stock?
Very minor power bolt-ons (intake, ignition, exhaust), swapped over a lot of parts from a 93 Cobra R (computer which is now chipped, 24 lb fuel injectors, MAF, transmission, gauge cluster) and full suspension/brake work.

[sflrainmaker01]

Very minor power bolt-ons (intake, ignition, exhaust), swapped over a lot of parts from a 93 Cobra R (computer which is now chipped, 24 lb fuel injectors, MAF, transmission, gauge cluster) and full suspension/brake work.

Nice! :up: Thanks for ya'lls help! I'll let you know how it turns out. :beer:

[sflrainmaker01]

FWIW, I am still waiting for the replacement coil from MSD, however, I still couldn't get the car to start.:mad: So, I while sorting through some of my 5.0 parts, I came across an old distributor. Don't recall which 5.0 it came from, but whatever. I cleaned it up and had the TFI module tested (which checked out fine) and yanked the "new" reman Cardone out and put in the old one. Guess what? She fired right up! :beer: I guess I wasn't paying to much attention as to whether I was getting reman or new. :rolleyes: Needless to say, I am returning that POS and upgrading to a new one. It must have been the PIP sensor that was not working correctly. I am not sure if it is worth the extra $$ to pony up for a new MSD Billet one. I heard lots of + and - about their stuff. Anyway, I timed her and put the car back together for a test drive tonight. I am pretty sure it will drive basically the same as before, since I still need to do a Mass Air Conversion. But, she's alive again! :banana: