Intermitent hot start issue

roachie

roachie

Taco Master
Joined
Nov 2, 2007
Messages
11,133
This is driving me insane. Truck only does this at 3 drive-thoughs near where I work.

I pull up behind a car at the speaker, shut truck off, wait on person to order, start truck and pull up, turn off, order, start.....hits on one cylinder........then crank for 20 seconds until it lights.

It only does this at the speaker, never anywhere else, truck isn't up to operating temp when it pulls this chit.

II HRVP
AD2
7x12


Ideas?
 
Mine does that too! Except I know why mine does it, I have a damn cheap ace alarm that came installed on the truck when I got it. Only happens in drive throughs, usually when I'm in a hurry and/or there is a line of cars behind me. Very very frustrating...
 
RF interferance. You should wrap your truck in aluminum foil.



LOL
 
Quit shutting it off before you pull up to the speaker. If you're concerned about the other people getting their order in, just hang back a few feet, makes all the difference in the world.

Check all your grounds to start with. Maybe try bumping the starter and let the AD run for a few seconds before cranking.
 
Still doing this, I have determined that it hates taco bell and wendy's.

Truck needs sit for atleast 5 min before it will fire. And even then I have to power off the VP, ECM, and AD relays (breaker underhood). Then its still a crapshoot.

Could this be the cam sensor?
 
Funny you mention this now Roach, my truck has the same problem, but mine is P-pumped now. It always starts cold, but every now and then, after it gets warmed up, if I shut it off and try to start it again it won't crank. I was thinking it was my starter solenoid, but who knows?

I have a new starter, but the post that the power cable bolts too feels "loose" to me? Currently I just leave it running if I can or park somewhere that I can let it roll and pop start it just in case it won't start.
 
if its only 2 particular spots, I am almost leaning toward RF interference like someone else said. Are these particular drive-throughs on an angle or something that would make the truck sit funny? What about the overflow valve?
 
Flat ground. It has to be RF. I just cant figure out what part its screwing with. The VP and AD relays are the same, I can hear it run so it has to be in the ecm or vp.


It will eventually sputter on one cyl then go back to nothing. Also, my juice still works (showing info) so I would assume the ecm is working. I did note that it wasnt showing any rpm while cranking on the juice, that leads me to the cam or crank sensor but it may not show rpm until its running.
 
What fuel pressure are you running to the AD? Do you have it wired through the stock lift pump wiring or do you have it wired to run whenever the key is on?

VP44's don't like much fuel pressure during startup....

Paul
 
I have no clue on the pressure. It starts fine anywhere but the drive though. NEVER does this anywhere else.

It is ran using the stock wiring to turn it on, power is coming through one of the ford relays in the truck.
 
Wonder if removing the ECM and wrapping it with that chrome duct tape would help...
 
roachie said:
Wonder if removing the ECM and wrapping it with that chrome duct tape would help...
Click to expand...

That and the harness from the ECM to VP. If it is indeed RF, its going to affect the harness more because it acts as the antenna so to speak.
 
If it is RF interference, and you do end up wrapping the harness with foil or something conductive, solder a ground wire on one end and ground it. It will need a path to ground to shunt the interference to ground or it may couple back on to the harness anyway.
 
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