But back to the EFI aspect for just a bit, the hesitation issue (still exists when it runs?) could easily be something with the system running lean.

But the out and out dying, yeah I'd have to say might as well try an ignition module at this point. With yours being a Pertronix though, which distributor did you get? Regular Ignitor, or one of their HEI clones? Guessing Ignitor since you said 2-wire earlier. Just curious more than anything else at this point.
When you're messing about with it, check the wires closely. Not only the condition of the wires, but the connections/splices where you tapped into power. I've seen both a pinched wire (where it enters the distributor body) and splices that look good act weird intermittently.

Of course, as 1976 F-250 mentioned before, you can even get a bad module right out of the box. Has never happened to me, or anyone I know (Including customers) but I have heard of it happening. So it can't be ruled out. And I'm not aware of any real testing that you can do to determine if it's good or bad.
Like a Dura Spark stator can be tested with an ohm-meter for a specific range, I don't think that's something you can do with an Ignitor.

Hmm, I don't remember if we talked about it, but do you have a tach in this truck? Just wondering in case you can watch the needle while it's running and when it dies. You can probably tell between fuel and spark when it dies, but a tachometer needle is a really good diagnostic tool as well.
If when the engine dies the needle drops like a rock to zero even before the engine has stopped spinning, it's an ignition issue. If it keeps reading as the engine finally stops spinning, it's a fueling issue.

Good luck.

Paul

 

Don' have a tack but the control box for the efi that you use to set parameters and fuel trim I have used with the truck running. Rpms drop immediately and the n it dies. Sometimes it fires right back up and most of the time it dont. Ign box will be here Thursday so I will let you know this weekend. I got the ignotor dust. Nothing to fancy just wanted some upgrades I didn' have to worry about for a while. Didn' work out so good so far. Thanks for help

 

Well now I'm at a stopping point. Wired in the msd 6A and won't start. Probably messed something up. But the wirings for the msd and the fitech are completely different so I gotta call fitech and msd tomorrow and see what the hell i can do. I also don't have a tach So im not sure where to connect the tach wire for the msd. Might need more parts. I'm so close to scrapping the whole set up and going back to carburetor. Frustrating as hell

 

MSD = "My Spark Died"

Kidding.. sorry to hear yer having trouble you'll get er licked.

 

There was another thread here, or on another forum, that listed a multi-spark distributor as being incompatible with the FiTech and causing his to run erratically. But I don't think that's the same issue when it's a separate control module doing the sparking. In that other case, I'm not sure if the computer was controlling the timing or if it was just doing the fuel.
Still, never hurts to check.

For the tach, it all depends on the tach usually. In the case of the FiTech it may be fine with a tach signal from the side contact point on the MSD box. Wouldn't that be nice!

Paul

 

Okay so I had to pull the MSD ignition out. I talked to fitech about the wiring and I wired it the way they told me to and it still would not start. So I yanked the MSD. And the truck fired right up. So I'm back to my original problem. 390 fitech fuel injection pertronix 2 wire distributor. Truck stumbles and dies sometimes. Restarts every now and then but when it doesn't refire it's done until I go back in and check Spark and then all the sudden fires back up without me doing anything except pulling number one spark plug to check Spark. So it's kind of leading me to a wiring issue. I have checked on my grounds all my connections and I'm at a loss

 

So I thought I narrowed it down to the ignotor in the distributor but that didn't change anything. I have no codes with the fitech but not sure if there is something else. It's falling on its face if it's cold or at operating temp. I have no clue what else to check. I have already bumped up my fuel pressure. Fitech and pertonix can't help or are no help. Very close to going back to carburetor and calling it good. Any one got something else for me to check? I'm at a lose.

 

Well like all the EFI TBI installs I've discussed over the years, it sure sounds like the cold enrichment isn't doing it's thing. But whether that's due to a sensor, or simple programming issue, it's hard to say maybe. But if the readout will tell you what the coolant temp sensor is reading at any given time, that should tell you if the sensor itself is giving forth with the proper info.
If that's the case, what's the AFR reading when cold and stepping on the throttle. Should not go up, but down in numbers when trying to accelerate I would think.

And have you followed along what the timing is doing at all these times when it's not running properly? I forget if you can watch the fuel ratios when it's running, but with a timing light you can see what it's doing with regard to timing advance.

And I forget if you tried to advance the timing a few degrees, or even change the vacuum advance from the usual ported, to full manifold vacuum just as an experiment.
In fact, even though I'm usually a ported vacuum kind of guy, I say it's well worth a quick experiment to see if the vacuum advance swap can make it any better..
Heck, even if it makes it worse, at least it's a change to note!

Paul

 

I will try the vacuum tomorrow when I get home. Won't hurt anything. I will check the AFR also and see what it does. Thanks for the tip

 

I have had similar issues that were due to the Magnetic Pickup in the distributor and the Ignition box/ECU specifically the magnetic pick-up when it's been running a while and works when it cools. And because its EFI I suggest checking throttle position sensor and/or the blade adjustment in your throttle body. I don't think it's getting enough air.

 

So I changed the vacuum line to come straight off the intake since there was nothing coming from the efi where it was hooked to originally. I then checked the AFR signal and when I stepped on the throttle the AFR number went up. Only a little bit but still went up. The truck did run better for a little bit. But then it started to stumble and died twice. I thought I could see Spark on the EFI display but I cannot. I don't think I can change the plates on the EFI. From what I have read fitech says it doesn't change anything. But I could be wrong

 

Well I talked to pertonix again and not much luck. Just told me to check my grounds and make sure they are good. I just don't see how it will sit and idle all day long but once I put a load on it she starts to fail. Back to the drawing board again. Summer is almost over . This sucks

 

Up by how much, and to what? A higher number is usually leaner, and that would explain why it's losing power or running worse under acceleration. Lean flame-out if extreme enough.
Under light accel, I think you would be looking for something in the 12-13.5 to 1 ratio, and under heavy accel you'd be wanting more in the 12 range or so. But don't hold me to those numbers exactly. Just general references.
If it's going up higher than those and leaning out, you would certainly not have happy acceleration.

Paul

 

Weak spark, bad plug gaps, fouled plugs, bad plugs, lean fuel mixture.
Any single one of those could cause trouble upon acceleration. Add more than one and it's a recipe for suckage.

Paul