Recently I been having weird starting problems with 2007 hummer h3, sometimes the car will crank but won't start keep cranking and pressing on gas and eventually starts, sometimes it start right away, I have new battery terminals end cus you recommended me before to change them so those been done for a while and the battery is recently new like few months ago, and I checked it and its healthy. checked the battery wires they are tight and good. my ECU is tuned so my pass lock is disabled. it just started few days ago. no check engine light. is it the starter? ignition switch? I am trying to figure it out, and any help I would appreciate it

 

More just maintenance suggestions then anything to offer.
Maybe change spark plugs, clean throttle body and maf, bottle of techron...
Are there any codes stored?

 

I always put seafoam I cleaned the maf and put spark plugs not that long ago and throttle body is clean filter is also clean. No codes I just don’t know why it start to happen all the sudden specially I really keep the car well maintained

 

instead of throwing parts at it check your fuel pressure when you have the issue.

 

How can I check the fuel pressure sir? So when I try to start it if it crank but doesn’t start check it?

 

yes.
you connect the fuel pressure gauge to your injector fuel rail. if there is no pressure or very low pressure then you are having a fuel starvation or fuel delivery issue most likely from a failing/ clogged fuel pump or bad fuel pump connections. some scanners will show you fuel pressure and also manually turn the pump on or off. a GM tech2 scanner can definitely accomplish that.

 

Whats considered a good pressure and low pressure? What the number suppose to be?

 

https://www.hummerforums.com/forum/h...re-spec-35934/

 

I was just reading this thread and immediately though this sounds fuel related. I had a '13 a Charger SRT8 that had the same problem. Turned out to be "cold enrichment" injector that went bad. Guess that car had a 9th injector for this purpose.....never looked into it to confirm. It was a warranty repair.

 

Thats crazy how to check the injector ?