hi all, newbie here. im working on an 03 s10 blazer. ive done some searching about possible ignition switch, or bcm, or ?

it will start with no problems at all everytime one day, then not at all the next. will crank over, but wont start. heres some syptoms ive noticed, hope you can help me diagnose this before i start throwing parts at it.

when i open the door, the fuel gauge drops to empty, if i get in and shut the door and dont touch anything for say 20 seconds, it will come back up to where the tank level is. as soon as i TOUCH the key to the ignition cylinder (not even insert it just touch it) the gauge will drop to empty again. this happens everytime.

sometimes it will start with no trouble at all, several times in one day. then again sometimes it wont start at all after several repeated attempts. i went to attempt the ten minute wait and see if fuel override kicks in, but of course it started when i went out to try it (go figure). yet the fuel gauge drops to E whether it starts or not (do they all do this??) once running it reads the proper level all the time.

the security light flashes when the door is opened, and goes out once the key is turned to on.

im kinda stumped here, hope you guys can shed some light on situation.

thanks in advance, awesome forum here, def love all the info ive read so far.

 

BUMP
replaced igniton switch with new ac delco switch. still getting the same problem. any ideas??

 

well since you have replaced the ignition switch... when it doesn't start up but cranks, you have eliminated the neutral saftey switch. So now you have to see if you have fuel pressure and spark at that time. I agree, don't throw parts at it..... prove whatever you think is bad first.

I read and reread what you have checked and noticed, but for now I blame gremlins until I see more proof otherwise.