Brad Huff

I recently purchased a 5.0 Monster from a person that I feel is reputable and had it delivered. The car was unloaded at the local high school and driven 3 miles to my house and it died in my driveway. If you try to start it again right away it will only run for a few seconds, if at all. If you leave it set for a few hours it will restart but only run for a minute and a half or so then it dies again. When it dies I get out my spark tester and verify that I have no spark. If I wait it will eventually start to jump a spark across my spark tester. If I hook the coil wire back up then it will run but only for a very short time and the process repeats. At first I suspected either the PIP module or the ICM, which has been relocated off the distributor, but if you did not know any details about the ignition you would swear that it ran out of gas. The gas tank is full, and the fuel pump is running. Right now it has the fuel pump wiring set up as described in Martin's manual. I have not had it running long enough to take it out on the road. In fact, I have only been able to drive it about 30 feet. What I know for sure is that when it dies, I don’t have spark. My problem is that I am a carburetor guy and I am just learning about fuel injection. I don’t yet know all of the “rules”. If you leave it set until the next day it always starts and runs for a few minutes or so but it will then act like it is going to die, it coughs and sputters and the computer tries to recover. It does recover for about ten seconds or so then it will die. The symptoms are like maybe it has a completely plugged fuel filter or it acts like someone threw a couple of condoms in the gas tank. When the problem first occurred it would shut off clean like someone switched off the key but now it kind of gives you a warning. I can’t get it running long enough to warm it up for a KOER test plus I would never trust it given its condition.

I have some basic questions about fuel injection.

1) If you have no fuel will the computer shut off the spark? Or is the spark always there regardless? In other words could I be being fooled into thinking that it’s an ignition problem when it really is a fuel problem?

2) I believe that if you don’t have spark the fuel will shut off correct? I think that normally the spark is present when you first crank an engine as is fuel but I think that if it cranks for several seconds without starting the injectors will be shut off.

There isn’t a Schrader valve on the fuel rail so I can’t easily check fuel pressure. I even pulled the Spout jumper off of the ignition to the computer because I read that this will sometimes allow the engine to run if the PIP was going bad. It made no difference. Any guidance with this will be greatly appreciated. Thank you in advance.-Brad

jrmotorsports55

No, low fuel does not cut spark. Spark should be there regardless.

Do you have another coil you can swap in to make sure that is not the issue (overheating/bad coil)? After that, I would start chasing wiring to ECU/relays, make sure the power to the ECU is not being cut (bad power relay/wiring).

tbone heller

I remember a few people having issues with the way that the Ford fuel pump was wired into the Mazda harness. I totally eliminated all Mazda wiring from my build. I wired my fuel pump up the same as it is in a Mustang including the inertia switch.

As far as your ignition goes, It sounds like a bad coil, stator, or module. This is where having a buddy with a "test distributor" would come in handy. Also check to be sure somebody didn't butcher up the wiring to the module when they relocated it from its designed location.

mrmustang

Your current "TFI" module is going bad. Replace it, change your oil and filter (there is fuel contamination if you have tried to start and restart), change your fuel filter, and fire it back up.

In addition, from experience, I highly recommend a TFI relocation kit from Jason (CLICK HERE)

Bill