Have 2002 Yukon that won't start if under 3/8 or 1\4 of gas

Lots of help here. You need a good auto-electrician with a pro grade scan tool. There are soooo many modules in that vehicle and I have a vague recollection there is a box of tricks under the seat!.

https://www.google.com/search?q=2002+yukon+won%27t+start

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If it is a fuel line you would smell and see gas drip where you park most likely, unless it is up over frame and drying prior to hitting the ground which is possible. Smell gas while parked? Get up under it and look for wet spots on fuel line. Are you getting fuel through line? Pull from under hood and check pressure.

the fuel pump is cooled by gas so if u run it low alot or {OUT} it can burn it up
keep that tank at 1/4 or u will pay!!!

this is a quick easy way to see if you have a fuel pump problem,get under the vehicle and hit the fuel tank with your hand viguriously ,this will vibrate debree or loose wires ,Im telling you this because my 03 suburban did this same thing and after cking everything like you did i got under my vehicle{lay down beside the drivers door just enough to reach fuel tank} at bottom.then try to start vehicle if it starts then you know its fuel pump in gas tank.hope this is helpful

Try leaning under the truck and hitting the gas tank with a basebal bat while someone else is tring to start it. My bet is that you need a fuel pump, if it starts when you hit the tank, have the pump replaced soon.

have the fuel pressure and volume tested with a gage.this sounds and acts like a fuel pump problem.check the fuel filter as well and replace anyways.when it won`t start but cranks can you hear the fuel pump running.listen at the fuel filler neck with the gas cap off.if you can`t listen under the car at the fuel tank you should hear it running/if not hit the gas tank and if the car starts then the pump needs replacing.you should check to make sure you are getting spark at the spark plugs to eliminate an ignition problem but i think its fuel.

possiable fuel pump, this sounds dumb but it works at times hit the gas tank in the center when it wont start and see if it starts.

I had the same problem. I had a few different mechanics tell me that the fuel pump is starting to go out when it does that. The fuel pump is located in the fuel tank, and the gasoline keeps the pump cool and lubricated. When the fuel tank is less than a 1/4 full, the pump is not submerged anymore, and can have trouble sending gas to the engine. My emergency fix was to get underneath the car on the driver's side and bang on the gas tank about three times. It will start up, and will run great unless you turn your engine off. But eventually you're going to need a new fuel pump. Once I replaced it, the problem went away.

try to put 2 gal of gas.
if you run out of gas, the system require little more than a gal of gas to get from the pump in the tank through the filter to the injector. Approximately 1gal just to pressured the fuel rail.

i would say that you could have one of two issues.
1 being a bad (intermitten) ground.
2 the rheostat on the sender is bad.
i have had this issue with a 1995 impala. the only issue is that you have to drop the tank to fix it.
i have tried to find the rheostat only for my car but gm doesn't sell it seperatly.
first , check the ground comming out of the tank and make sure that its good. if not, a new sender is needed.


hope this helps



dave