P0300 and Gas gauge reading empty

[alc5m]

Anyone ever had this problem before?

I went and test drove an 03 z71 hoe, worked great ran great, only 75k

handed over the checks and started to drive it off the lot and all of a sudden CEL is on, truck is shaking and right before that happened gas gauge went to E

I was told they put in 6 gallons, and two days prior there was a half tank of gas

so i brought it back in right away and they said they'd fix it, but what im wondering is what could cause this

cause like i said i test drove it with no issues

Thanks

 

[DeepSeaFish]

Sounds like a possible fuel sending unit gone bad. Usually the case when the needle pegs to E while driving.

 

[alc5m]

that was the first thing i said to my dad when we were talking to the mechanic, but i didnt know if there were any other things, i mean if its the sending unit, then not enough fuel would be getting to the engine causing a misfire? or am i thinking about that wrong

with this dealer i could spend 2000 bucks and get gaskets seals and any other mechanical problems covered for the next 36000 miles or 3 yrs, so basically if i blow the engine or tranny it would be fixed for a hundred buck deductible