Fuel System Problems

[Sierras&Supras]

I have a 2000 GMC sierra with a 4.8L V8 with 240,000 miles. About 5000 miles ago my check engine light came on and the code was bank 1 & 2 were running lean. Bought some injector cleaner, dumped it into the fuel tank and the light went off. about 2 weeks ago the light came back on and out of nowhere one cold december morning i went to start the truck and it sounded horrible. i made it to autozone where the read the codes again and it said both banks are running lean again, but now cyl #8 is misfiring and possibly more are misfiring. Now the truck is running VERY VERY poorly so i parked it for a week until i had time to work on it. When i got time i pulled it in the garage and shut it off, but i wasnt centered so i tried starting it again but it wouldnt start. truck cranks and cranks all day but will not start. i replaced fuel pump about 2 years ago and the fuel filter about 3 years ago. i checked the schrader core on the fuel rail on the motor and it definatly has fuel pressure, fuel squirted out all over and when i turn my key to the run position before starting it, i hear the fuel pump energize and prime the lines. WHAT IS GOING ON!!!! I CANT FIGURE IT OUT!!! Any help is greatly appreciated!!!

 

[Sierras&Supras]

Update

Apparently it is not a fuel problem. I took my throttle body apart and cleaned it, then the same to my Airflow Meter. Then i tried to start the truck while spraying ether into the intake and still nothing. Now im thinking theres no spark.

 

[jagtoes]

What were the first codes? Take that code and put it into google as p0XXXX obdii code and see what you get for the definition and the possible repairs. You may have a crank position sensor problem but I would think it would set a code.

 

[Molson02536]

Apparently it is not a fuel problem. I took my throttle body apart and cleaned it, then the same to my Airflow Meter. Then i tried to start the truck while spraying ether into the intake and still nothing. Now im thinking theres no spark.

Have the ICM checked out after you check the wire harness and lead. Start with that and keep us posted and also check your fuses.

Good luck and keep us posted.