TFI Module Issue? Or...

[Catch22556]

We've had a triple digit heatwave here local and my 84 didn't like it. Took it up in the mountains and it started sputtering out on me before it finally just died, it would fire back up and idle, but wouldn't rev at all without dying until it cooled back down. Figured it was just vapor locking since the engine compartment was HOT. Now it doesn't matter if it's warm or cold, she spits and sputters and bucks pretty bad with a load on it. Fires right up and idles just fine though. It's acting like it's a timing issue but it was running good before the trip up the mountain, maybe TFI module? Just replaced it 2 weeks ago due to a typical no start condition but that doesn't mean anything with this heat, I was just under the impression with a TFI module it either works or it doesn't.

Bone stock 2.8 with just a computer and emissions delete and a non-feedback 2150.

 

[RonD]

You could put a timing light on it and see.
Try without SPOUT hooked up first, and REV engine to make sure distributors Centrifugal Advance is working, then do it with SPOUT hooked up to see if Computer's advance is also working.


Might be time to get a Duraspark distributor and HEI module, then no worries about spark.
Super simple wiring and very reliable system.

Coils can get heat sensitive as well, but very hard to test for that.

 

[Catch22556]

I've been needing to time it right since i got it, probably go pick up a new light tomorrow and set it right. It was running good before, had good power and mileage was decent before the heat got to it is what's odd to me and the timing hasn't changed at all. Dizzy is still in the exact spot it was before so it didn't shift, i marked it.

I tried doing the Duraspark swap on this one like i did my old choptop 84 but couldn't find a dizzy anywhere. Nobody local could order one and i couldn't find one online or in any of the junkyards so i'm SOL for now. I also put a new Motorcraft coil in right before i replaced the TFI module a couple weeks ago but i don't think it's that, it does it when it's warm or cold after that last battle it had with the heat.

 

[AndyB.]

There is no centrifugal advance with a TFI distributor.

The modules are pretty inexpensive and failure prone as they age, but I'd try to do some troubleshooting first.

 

[Tedybear]

This is going to sound odd....

With the engine running reach around and CAREFULLY!!!! grab the connector that plugs into the TFI. Give it a few wiggles and pulls. Over time the connector can get weak at the pin's and then you'll have a whole bunch of ghost problems. We found ours on the old BII we used to have doing that. I moved the harness at the TFI and the engine ran like crap and then cut out completely. Thankfully NAPA sells the pig tail harness for that.

S-

(Did I mention CAREFULLY!!....It's usually pretty hot and with moving parts.....)

 

[RonD]

Yes, no centrifugal advance in TFI distributor, oops, and I knew that

 

[Catch22556]

Timed it properly this morning and no change at all. Ended up replacing the on-carb fuel filter I've been meaning to change with a see-through type at the frame rail. I got rid of the metal line with standard 5/16" fuel hose while i was there for heat reasons and noticed that there was almost no flow through the filter, DOH! Changed out the mechanical pump and she's golden so far, fingers crossed. What a huge PITA is was to replace that pump though, next time i'm probably going to put the extra coin down and just go with an inline electric pump and ditch the mechanical. Between dropping the m5od out of the DD exploder to change out the clutch slave cylinder and doing the fuel pump in the B2 by myself I'm wiped, thanks for the feedback everyone!

 

[enginepaul]

Considering:
"Bone stock 2.8 with just a computer and emissions delete and a non-feedback 2150. "
You might try clearing the codes. The computer needs all the sensors to work properly.