A little help with my son’s 2003 Tahoe

[Ash4l]

Hello, my son is having a little trouble out of his 2003 Tahoe. It died on him the other day and we suspected fuel pump because we didn’t hear the pump coming on. We replaced the pump but still no power to pump. Today we hot wired the pump to get it to run but it would still not crank. All fuses and relays seem to be fine. It will try to crank once then when you shut it off again and turn the switch there’s nothing. Any help would be appreciated.

 

[Fless]

Welcome to the forum from Colorado!

Verify that the battery is fully charged and has cranking capacity. How old is it, and has it been tested lately?

Did the pump run when you hot wired it? Use a fuel pressure gauge while you hot wire the pump to see if it runs and brings the pressure up.

I suggest bypassing the starter relay to see if the main cables are intact and can handle the current. This thread shows how to do that, but there will be several YouTube videos, so do some searching if you'd rather:

no crank no start intermittent problem

Sorry to bring this thread back from the dead. My truck does the same thing but it will start with my remote start with no problems. I replace the starter last winter. Should I be looking at the ignition switch? Thanks That would be a good place to look. I don't know what year make/model your...

www.tahoeyukonforum.com

I'd also suggest doing a voltage drop test:

 

[Ash4l]

Thanks for the reply! Yes. The battery is good. It is only about 2 months old. The pump ran when it was hot wired. I’ll look over the video and try that when we get back to it.

 

[rockola1971]

After checking Ign A and Crank Fuse and both negative and positive cable battery connections at the battery, starter and engine block ground(corrosion is usually the culprit here), I would suspect the ignition switch. If you are familar with how to use a voltmeter I can tell you where to check using the following schematics. I own (2) 2003 Tahoe LT's.

 

[Ash4l]

we changed the ignition switch about a year ago. I guess it could have gone bad in that time. We’ll check everything you suggested and maybe replace the switch again.

 

[Fless]

we changed the ignition switch about a year ago. I guess it could have gone bad in that time. We’ll check everything you suggested and maybe replace the switch again.

Have @rockola1971 get you some test info before condemning the switch. In my experience there's nothing worse than introducing new parts as variables.