SPONSORED LINKS

My truck cranks normally but won't start?

Tiny
OUTLAWSGHOST
  • MEMBER
  • 2001 CHEVROLET SILVERADO
  • 6.0L
  • V8
  • 4WD
  • AUTOMATIC
  • 200,000 MILES
My truck cranks normally but won't start. It will on ether but shuts off. I've replaced fuel pump and filter, plugs wires, cam shaft sensor, and crank sensor. Good fuel pressure to fuel rails. Coils and injectors are good. It's got spark. Fuses and relays are all good. Also replaced battery. Alternator and starter are good. Nobody can seem to figure it out. Please help.
SPONSORED LINKS
Sunday, November 29th, 2020 AT 11:55 PM

8 Replies

Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Good morning,

Did you verify power to the fuel pump while cranking and when you first turn the key to on?

I attached a diagram of the relay and the pump for you. You need to verify power to the relay first on pin 30.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

https://www.2carpros.com/articles/how-to-check-wiring

Then 85 gets power directly from the ECM.

The grey wire at the pump is what needs power.

Roy

Images (Click to make bigger)
Thumb
Thumb
Thumb
Thumb
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Monday, January 25th, 2021 AT 10:16 AM
Tiny
OUTLAWSGHOST
  • MEMBER
  • 5 POSTS
Hi Roy, I had my neighbor check it out and the pump and relay are indeed getting power.
Was this
answer
helpful?
Yes
No
Monday, January 25th, 2021 AT 10:16 AM
Tiny
OUTLAWSGHOST
  • MEMBER
  • 5 POSTS
I have also changed the MAF sensor when I replaced all the rest of those parts.
Was this
answer
helpful?
Yes
No
Monday, January 25th, 2021 AT 10:16 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
If the pump is getting power and not running, then you either have a bad pump or ground.

Did you verify no fuel pressure?

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Roy
Was this
answer
helpful?
Yes
No
Monday, January 25th, 2021 AT 10:16 AM
Tiny
OUTLAWSGHOST
  • MEMBER
  • 5 POSTS
Fuel injected is getting power and running. I checked the fuel pressure at fuel rails and each time it's between 50 and 60.
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Monday, January 25th, 2021 AT 10:16 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Okay, next you will need a noid lid light to attach to one injector and crank the engine. It should flash indicating the ECM is commanding the injector open to flow fuel.

You can rent one at a parts store for this test.

Roy
Was this
answer
helpful?
Yes
No
Monday, January 25th, 2021 AT 10:16 AM
Tiny
OUTLAWSGHOST
  • MEMBER
  • 5 POSTS
Okay, I'll try that next. Thank you.
Was this
answer
helpful?
Yes
No
Monday, January 25th, 2021 AT 10:16 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
You are welcome.

Roy
Was this
answer
helpful?
Yes
No
Monday, January 25th, 2021 AT 10:16 AM

Please login or register to post a reply.

Related Engine Not Running Content

How to fix an engine that wont start
VIDEO
How to fix an engine that wont start
Instructional repair video
Engine Not Starting - Top 3 Easy Steps
GUIDE
Engine Not Starting - Top 3 Easy Steps
Over the past 20 years on 2CarPros we have identified the top three problems that are easily fixed. This can save you a trip to the repair garage or calling a tow truck and...
VIEW MORE

Sponsored links