Dying while stopped

[Fry]

Took my 76 out today for a little drive. Everything was going good until I stopped at a stop sign. And my bronco just died. Was able to turn it off and it started right up but it seems when im stopped in traffic or at a stop sign the bronco wants to die. I have had this problem before backing up out of my driveway as well. If I put it in reverse and back up then press the brake sometimes it dies and I have to turn it off and on again. Any ideas what this could be ? I’ve also had it die while I had it warming up in the drive way idling. I know it could be a million things but any suggestions on where to start?

A little about the truck. It’s a 351w with fast ez efi. Automatic transmission.

 

[m_m70]

It would help if you had some info on your truck......
auto/manual
carb/injected
ignition
etc.........

Thanks!

 

[ared77]

Vac leak maybe?

 

[73azbronco]

Who put the FAST in, take it back to them.

 

[DirtDonk]

Does the computer control the ignition too?
Is your foot always on the brake when this happens? Maybe there’s a leak in the vacuum booster.
Has it had a tuneup in recent years?
I had one other question in mind, but a squirrel ran by, and I forgot what it was!

 

[Fry]

Does the computer control the ignition too?
Is your foot always on the brake when this happens? Maybe there’s a leak in the vacuum booster.
Has it had a tuneup in recent years?
I had one other question in mind, but a squirrel ran by, and I forgot what it was!

I’m unsure if the computer controls the ignition. My foot is on the brake when it dies. I recently bought it 3 months ago and the guy I got it from didn’t have much info on it. Wish I had more Info on it.

 

[Wild horse 75]

I’m unsure if the computer controls the ignition. My foot is on the brake when it dies. I recently bought it 3 months ago and the guy I got it from didn’t have much info on it. Wish I had more Info on it.

Vacuum power brakes? Try plugging the vac line to the booster and see If it changes. Could be a leak inside the booster.

 

[DirtDonk]

I recently bought it 3 months ago and the guy I got it from didn’t have much info on it.

That’s an unfortunately all too common problem these days. With all the buying, selling, and especially quick flipping that Broncos are going through these days, half the sellers have only had the vehicle for a couple of weeks or months and don’t know anything about them.
Or they say they don’t, to cover their tracks when they decided to sell it because it had problems.
Now maybe that’s not the case here, and maybe it’s just a simple problem that developed at the time you bought it. But it means you’re going to have to go down a whole list of things to check.

Have you tried to restart it without turning the key off first? As in, just turn it to start immediately to see if it will re-fire.
Not sure if it will tell us anything, but it might help eliminate some electronic things, if it just restarts without resetting first.

 

[Fry]

That’s an unfortunately all too common problem these days. With all the buying, selling, and especially quick flipping that Broncos are going through these days, half the sellers have only had the vehicle for a couple of weeks or months and don’t know anything about them.
Or they say they don’t, to cover their tracks when they decided to sell it because it had problems.
Now maybe that’s not the case here, and maybe it’s just a simple problem that developed at the time you bought it. But it means you’re going to have to go down a whole list of things to check.

Have you tried to restart it without turning the key off first? As in, just turn it to start immediately to see if it will re-fire.
Not sure if it will tell us anything, but it might help eliminate some electronic things, if it just restarts without resetting first.

I’ll definitely give that a try next time I take it out. Hopefully I can do so this weekend. And come back here with an update.

 

[73azbronco]

so, whats the battery voltage, i bet the battery is low/dead.

 

[Fry]

so, whats the battery voltage, i bet the battery is low/dead.

I replaced the battery like a month and a half ago.

 

[DirtDonk]

So let’s get something out in the open right out of the gate. New, does not mean it’s still good.
While your problem could be any number of things at the moment, you can’t assume that because something is new, newer, or whatever, means that it’s gonna keep working for you.
Luckily for us, batteries are one of the more reliable good parts these days. But we’ve heard way too many stories of woe, when someone gets a new battery and it starts dying on them, within weeks or months. And that’s if they’re lucky and it doesn’t start dying on them within days of installing!
This is just an unfortunate fact of life for us these days. Some parts categories are worse than others, but everything is suspect.
It wouldn’t hurt for you to measure the voltage after the truck has sat overnight, plus while it’s charging with the engine running.
Just so you know what’s going on in the system.
But if it cranks the starter and motor over easily, it’s probably still doing its job just fine.

With some things you can trust, but verify.
With other things, unfortunately, you mistrust and verify multiple times!

 

[Fry]

I did notice I have a small transfer case leak that I plan on taking care of soon. Could the random dying be related to this?

 

[pcf_mark]

I did notice I have a small transfer case leak that I plan on taking care of soon. Could the random dying be related to this?

No that would not be related.

Maybe some underhood pictures to show what and how everything is installed will help. If it is EZ EFI related that is going to be tough to remote troubleshoot like most EFI issues.

In general check the wiring - just follow it along to see if it is loose, has a bad connection, is chaffed.
Your IAC (idle air control) motor may be slow to respond to changes in throttle and that is why it is dying when you stop.