What did you do to your NBS GMT800 Tahoe/Yukon Today?

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seven9st surfer

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Next time this happens, take a rubber or plastic mallet and bang on the fuel tank. If it starts up after doing this, it is most likely your fuel pump.

Interesting. How does that work?

And this might be a coincidence, but if so, it's a big one. I've had it towed to the shop 4 or 5 times now. Each time, it's in my driveway, and won't start for like 2-3 days. But every time the tow truck picks it up and delivers it to the shop, it fires right up on the first try. Is there maybe something about the tilt from getting it onto the truck that would make it start again? Would a bad fuel pump do that? I always back into the driveway, so it's on a decline. Would that have an effect?

Also, I've never had any problems with rough idling or it cutting out once it's running. It's just about once every month or so, it refuses to start until I tow it to the shop, then it starts. It's driving me crazy.
 

clandr1

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Interesting. How does that work?

And this might be a coincidence, but if so, it's a big one. I've had it towed to the shop 4 or 5 times now. Each time, it's in my driveway, and won't start for like 2-3 days. But every time the tow truck picks it up and delivers it to the shop, it fires right up on the first try. Is there maybe something about the tilt from getting it onto the truck that would make it start again? Would a bad fuel pump do that? I always back into the driveway, so it's on a decline. Would that have an effect?

Also, I've never had any problems with rough idling or it cutting out once it's running. It's just about once every month or so, it refuses to start until I tow it to the shop, then it starts. It's driving me crazy.

Sometimes the brushes/contacts on the motor inside the fuel pump get old, corroded, or dirty, and I've read online (never needed to do it myself) that a good whack on the fuel tank will jar the brushes loose, or jar them across the bad spot. This lets the fuel pump motor start spinning again, providing fuel to the engine.

Total shot in the dark, but it's easy, cheap, and worth a shot. Good luck with it! Let me know if it helps.
 

JochenWoern

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Sometimes the brushes/contacts on the motor inside the fuel pump get old, corroded, or dirty, and I've read online (never needed to do it myself) that a good whack on the fuel tank will jar the brushes loose, or jar them across the bad spot. This lets the fuel pump motor start spinning again, providing fuel to the engine.

Total shot in the dark, but it's easy, cheap, and worth a shot. Good luck with it! Let me know if it helps.

I think it is the very similar situation with a starter, whack it with a hammer and it may turn a couple more times in order to get you home.

I am going to bet that it is your fuel pump and once you change the incline on the truck and the tow truck pulls it up on its bed, the angle changes and the fuel will get to the pump.

I am willing to bet that this never happens when the tank is completely full and the pump is fully submerged.
I was going to say that based on your sig pic, your driveway has an incline. Now you say you always back the truck into the drive, ..........pull in forward and I am as well going to bet that it will not happen as the pump will be submerged by the fuel as you changed the angle of the truck when it is parked in your drive.

What do you think? Does my theory seem to represent what is happening?
 
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Yngbld32

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My opinion, ...................... and nothing more, ......................

Put your old wheels back on, as they looked much nicer than the wheels with rubber bands for tires.

Don't worry. I have my old 20s still. For when I want to blend in....
 

chevync

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Anybody want breakfast this morning? haha This is after less than 3k miles on a rebuilt engine, shop pulled the covers off yesterday and the shop called me and this is the first thing I seen, both sides are the same, we hasn't found the CASTECH emblem, he should have the heads off completely today and give me a call so I can check them out.
 

seven9st surfer

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I think it is the very similar situation with a starter, whack it with a hammer and it may turn a couple more times in order to get you home.

I am going to bet that it is your fuel pump and once you change the incline on the truck and the tow truck pulls it up on its bed, the angle changes and the fuel will get to the pump.

I am willing to bet that this never happens when the tank is completely full and the pump is fully submerged.
I was going to say that based on your sig pic, your driveway has an incline. Now you say you always back the truck into the drive, ..........pull in forward and I am as well going to bet that it will not happen as the pump will be submerged by the fuel as you changed the angle of the truck when it is parked in your drive.

What do you think? Does my theory seem to represent what is happening?

That has to be it. Now that I think about it, I know the last 2 times it's happened it's been less than 1/4 tank. And for every single time it gets towed to fire up after that, it's not a coincidence. Would that throw a code though?
 

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