Another no start problem - any ideas? Tried all I know...

[TimQ]

I just left my '86 sitting in the local Wal-Mart parking lot because it wouldn't start. I'm looking for some ideas on what I can try when I go back in the morning before giving in and calling a tow truck.

A little history. It's a v6 with a 1-year old rebuilt q-jet. Just about 90k original miles. Automatic.

I had an intermittant stalling and starting issue a year ago. After replacing ignition modules, coils, plugs, cap, rotor, wires, fuel pump, fuel filter, and, in the end, the entire distributor, I finally tracked it down to a faulty ESC module (the box up behind the dashboard that messes with the timing based on engine knock). Once I figured that out m(as in, bypassed it), the truck has run perfectly since. That is, till the last few days.

For the last week or so, the truck won't start intermittantly. For example, on Friday, I drove a few miles to pick up a chair at a local shop. Came out, and no start. Decided to walk up the street and grab lunch at the local pizza shop...came back and it fired right up.

On Sunday, I took my father-in-law to look at computers at the mall. Come out, truck won't start. Got some starter fluid and sprayed some into the carb but nothing. We decide to have lunch. Come back...starts up.

Tonight, I decided to take a spin for a good 90 minutes or so. On the way in from my normal loop, I decided to stop at Wal-Mart. Come out...no start. Figuring the battery might be giving in (just got really cold here the last week and the cranking speed was a tad slow), I went back in and bought a new one. Put the new battery in and crank it. Cranking speed is way better but still no start. I decided to see if I just needed to wait. So, I go in the store and poke around...come back out 40 minutes later (you know...about how long it takes for lunch). Still nothing. Perhaps the truck knows I didn't actually eat this time??

So my wife comes to pick me up and I figure, why not try and jump it...maybe the new battery isn't fully charged. Still nothing.

My guess is, I will go back in the AM and it will start right up.

Here's what I know. I have spark to the plugs. I have at least 12volts or so at the wire going to the dizzy. I can hear fuel squirting in when I manually move the throttle.

Also, after the first incident of a starting problem last week, I put new plugs and wires on it, checked the dizzy to make sure all was in order, and even checked the fuel filter. I checked for voltage loss between the battery and the wire coming into the dizzy. That was fine.

So, I'm at a loss.

The truck is running great otherwise. After hitting it with some seafoam a few months back, it doesn't smoke on start up anymore, or hesitate when punching the throttle. I used to have to add a bit of oil every second time I filled the gas tank. I've gone 5 or 6 tanks since the last oil change (1000 miles at least) and I've not had to add any oil. I'm getting 12 mpg or so and thats with fairly agressive and fast driving. So I would think the engine is in reasonable shape. When I had the problem with the ESC and replaced the dizzy, I had the shop set the timing. So I'm pretty sure that is right.

So...what gives? Any ideas? Especially those I can try in the AM to get my truck out of the parking lot at Wal-Mart?

Thanks.
Tim Q