Here is a start. Have the pcm checked to seeif it's sending a signal to start the car if not then see if bcm is doing same as i'm sending diagrams for it. Here is also a tsb from gm that covers hard starting.
NOTE: GM┬ UPPER┬ ENGINE┬ AND┬ FUEL┬ INJECTOR┬ CLEANER┬ is┬ the┬ only┬ injector┬ cleaning┬ agent┬ approved┬ for┬ use┬ with┬ General┬ Motors┬ fuel┬ system┬ components.┬ Other
injector┬ cleaners┬ may┬ cause┬ damage┬ to┬ plastics, ┬ plated┬ metals┬ or┬ bearings.┬ General┬ Motors┬ has┬ completed┬ extensive┬ laboratory┬ testing┬ of┬ GM┬ Upper┬ Engine┬ and
Fuel┬ Injector┬ Cleaner, ┬ and┬ can┬ assure┬ its┬ compatibility┬ with┬ General┬ Motors┬ fuel┬ system┬ components, ┬ as┬ long┬ as┬ the┬ cleaning┬ procedure┬ is┬ followed┬ correctly.
There is also a thing called top tier gas that is not available at all gas companies that have to do with clean injectors. If you do short hops like less than 10 miles driven each way this can effect your car. Check with a dealer for specific tsb for this. It gives the stations where you are in U.S. And CAnada
Tuesday, December 27th, 2011 AT 10:13 PM