Fuel only gets to engine when tank is out of the vehicle

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AuroraGirl

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OK well took it for a 30 minute drive around Vancouver.

When its in Drive (yes I couldn't find one with a manual tranny -boo) it runs fine and there certainly feels like theres no loss of power.

But it is hesitating when it is warm and at idle. I had a circurcumstance where I breaked quite hard and the engine cut out, then when I restarted it it cut out as soon as I tried taking it out of park. I basically had to rev it high in park and jam it into drive quickly which isn't a sustainable way to treat a 40 year old gearbox.

When it is in drive, and i come to a stop at a red light, it doesn't cut out, but it feels like it is close to doing so.

Can't be a fuel delivery issue if i can floor it without any issues, but might get some compressed air into that idle circuit as someone previously mentioned.

Edit: Just drove 20 minutes and it actually was fine - idle was a little shaky but i didnt get the impression it was going to conk out. Also allowed me to shift gears. Probably just needed a drive.
sounds like a carb or vacuum related problem
Is your modulator line in good shape and your modulator new
It CAN be a fuel delivery issue, dont for a second assume its ruled out because it works when you are on the throttle. throttle cable, return springs, geometry(depending on carb) settings, internal debris, pump, etc... all still at play
 

Rusty Nail

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Brake booster.
Inspect the booster hose and check valve but i bet it's time for a new booster.

Plug that hose and duplicate the problem.
 
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Challis350

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sounds like a carb or vacuum related problem
Is your modulator line in good shape and your modulator new
It CAN be a fuel delivery issue, dont for a second assume its ruled out because it works when you are on the throttle. throttle cable, return springs, geometry(depending on carb) settings, internal debris, pump, etc... all still at play
I have no idea about the vacuum modulator tbh. Only bought this truck in September.
 

SirRobyn0

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OK well took it for a 30 minute drive around Vancouver.

When its in Drive (yes I couldn't find one with a manual tranny -boo) it runs fine and there certainly feels like theres no loss of power.

But it is hesitating when it is warm and at idle. I had a circurcumstance where I breaked quite hard and the engine cut out, then when I restarted it it cut out as soon as I tried taking it out of park. I basically had to rev it high in park and jam it into drive quickly which isn't a sustainable way to treat a 40 year old gearbox.

When it is in drive, and i come to a stop at a red light, it doesn't cut out, but it feels like it is close to doing so.

Can't be a fuel delivery issue if i can floor it without any issues, but might get some compressed air into that idle circuit as someone previously mentioned.

Edit: Just drove 20 minutes and it actually was fine - idle was a little shaky but i didnt get the impression it was going to conk out. Also allowed me to shift gears. Probably just needed a drive.
Any idea if it sat before you bought it? I would check the vacuum hoses and the brake booster, but I'd also put a bottle of seafoam in the gas tank and drive the entire tank though. If there is just a little varnish in the carb from sitting especially if it's a Q-jet often times it'll clean up after running a tank of fresh gas though it, the seafoam additive might help it bit too.
 

Ricko1966

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Okay I know several people have said check for a vacuum leak including the booster. Do it. If you have a big enough vacuum leak you will have to lean of mixture at idle but not a big enough leak to keep it running with more throttle. 2nd if it runs on the pedal but won't idle you could just need a basic tune up ignition pieces,timing,carb adjustment. 3rd you could have a plugged Idle circuit no guarantees on this but it's free and easy to try.From under the hood give it a good rev.. push the choke shut all the way abd stick your hand over it to good if seal as you can.The vacuum your engine is making is going to have to pull fuel through the idle jets because it can't pull vacuum anywhere else.Sometimes this will clean up an idle circuit
 

Challis350

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I didn't do anything. It just started working ever since I posted that video.

Idled badly for about an hour afterwards, but a few more blasts down the freeway and it was fine.
 

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I didn't do anything. It just started working ever since I posted that video.

Idled badly for about an hour afterwards, but a few more blasts down the freeway and it was fine.
Probably needed to be driven to blow things out, or get any air bubbles out
 

Rusty Nail

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I am an odd duck AG that is for sure, but I was only fooling around. That said, corporations are generally garbage in my opinion. Once an organization reaches a certain size accountability goes out the window. There are just too many moving parts to these massive conglomerates for it. I look at a corporation like I do the general population when it comes to public restrooms. Too many random faces in random places to police them all so most every public restroom is a sopping wet mess of an S show. Giant corporations are the same to me. A virtually unpoliceable sh!tshow and the reason we can't have nice things lol. I did very much appreciate the well structured educational reply though.
He called her "AG".
 

AuroraGirl

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Maybe it'll pass Sm.
a lot of people have said AG lol to refer to me. not much recent but its not new and its also not offensive[im not sure if thats what you meant or if youre just making conversation haha]
 

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