Engine New Rebuild Giving Me Headaches... Stalls and Dies Randomly

[spdsk8n]

Hi Gang,

Ive stalked these forums for quite some time... Normally I find the info I need in these helpful forums and Im on my way. This time however Im stumped. Ive had a fox 5.0 motor in my 66 convertible for many many years and its served me well. After showing its age and leaking oil, I decided to buy a new rebuilt short block and have a friend swap everything out for me. He did the initial engine swap for me so hes pretty familiar with mustangs and my car in general.

I recently had my motor rebuilt. The only thing that was replaced was a newer aluminum radiator and a MSD distributor and coil.

The problem crops up after a few minutes of driving... The car stumbles a little and then just dies and this is pretty much random. If I leave the key to run... and just try to crank it will never start back up... its just cranks away. If I switch to off and back to start and crank... It will fire up usually right away like that. If the car happens to die while Im going down the road... today I just figured out of I just go from off to on again the car begins to run again. This happens over and over.

Has anyone experienced anything like this before? Ive crawled the the various forums looking for info but most point to a fuel issue or a TFI module?

Ive begun to work thru this thread https://www.stangnet.com/mustang-forums/threads/mustang-cuts-out-and-dies-after-warm-up.827901/
to troubleshoot but wondered if anyone reading this would say... dude, its XYZ. ;-) One can hope at least.

Thanks everyone!

 

[General karthief]

hard to say 'this is whats wrong' without hands on, really hard without knowing more about your setup, efi or carb, what ignition system, what wiring harness, that kind of stuff.

 

[a91what]

I need more info but it sounds like another victim of the MSD! They are craptastic

 

[deathb4dismount]

I need more info but it sounds like another victim of the MSD! They are craptastic

Does MSD just make crappy Ford distributors? For everyone else they seem to be a must have. I have their cap, rotor, and coil and no issues

 

[a91what]

I have had 3 people with ignition problems I have helped... each time the msd distributor was the culprit.

 

[General karthief]

Likely it's quality control at the manufacturer.
or lack of.

 

[jrichker]

hard to say 'this is whats wrong' without hands on, really hard without knowing more about your setup, efi or carb, what ignition system, what wiring harness, that kind of stuff.

We are on the same page...
Right now there is no info about the car - EFI or carb, no mods listed. Makes it hard to troubleshoot when we don't know what the Op has.

 

[spdsk8n]

Reaching into my wayback brain... its been a while remembering what harness this thing had in it... lol.

The setup is a windsor-fox wiring harness... so its a premade spliced 66 into a late model 5.0 engine harness... This was working flawlessly when the motor was pulled to rebuild.

Motor is a rebuilt 5.0 EFI with AOD, Mallory fuel pump, Edelbrock intake and heads, Stock ignition other than the now new MSD pro billet distro and Streetfire coil. Using a stock, chipped and tuned Ford computer.

The only thing that was changed again was the radiator, distributor and coil. My dumbass threw the older parts away so it looks like Ill be picking up some stock parts to see if the distributor or coil is the culprit.

I guess my question is would the problems ive described be indicative of a distributor or coil issue? The car dies while headed down the road and a simple key off then back on and the car starts to run again? Weird.

Anyway... many thanks for the responses ive gotten back so far gang.

 

[General karthief]

Yes, the coil and/or distributor could be causing your problem, the chip could be corrupted also, does the wire harness include the data link for checking computer codes?

 

[spdsk8n]

Yes, the coil and/or distributor could be causing your problem, the chip could be corrupted also, does the wire harness include the data link for checking computer codes?

No there is no port for pulling codes... I have a 96 Impala so Im well versed in that arena and pulling codes because of that joy. lol.

Soooo buying a stock distributor or what do you recommend as a comparable distributor replacement to the MSD? I picked up the MSD a while back thru Summit so not sure about any return even if it is faulty.

 

[General karthief]

Without being able to check the ecu for possible codes I don't know where to go, as far as a distributor, stock reman from cardone, I'd see what's available on rockauto.

 

[LX Dave]

The problem crops up after a few minutes of driving... The car stumbles a little and then just dies and this is pretty much random. If I leave the key to run... and just try to crank it will never start back up... its just cranks away. If I switch to off and back to start and crank... It will fire up usually right away like that. If the car happens to die while Im going down the road... today I just figured out of I just go from off to on again the car begins to run again. This happens over and over.

Had a problem that matches your description to a tee. Would randomly die and had to turn the ignition off so it would restart. Just trying to restart it and it wouldn't fire. It finally left me stranded one day when it wouldn't start again. Got a pull home and just had a hunch so I swapped out the ignition module. Never had a problem again.