My 02 silverado had been having trouble starting so I replaced the fuel filter & it worked fine.(I replaced the fuel pump last year & I can hear it when the ignition is on.) the next morning it wouldnt start at all so I sprayed carb cleaner into it & it started right up, it will run after the cleaner has burned, it will even turn on/off as normally after that, but once it sits several hours it wont start again. I took off the throttle body & cleaned it careful not to damage any seals or sensors now its running really sluggish & the "service engine" light is on plus it still has has trouble starting. Was I not as careful as I thought? what do you guys suggest? Thanks in advance!