Hummer H3 For the Hummer driver who wants the rugged look and off road capabilities of the Hummer, but in a smaller size and with a more fuel economy friendly engine.

Not starting after gasket replacment

Thread Tools
 
Search this Thread
 
Old Mar 22, 2025 | 07:44 AM
  #1  
Coronetkevin's Avatar
Thread Starter
|
Junior Member
Joined: Jul 2019
Posts: 7
From: Ocala fl
Default Not starting after gasket replacment

Morning everyone,

Working on my daughter’s 2006 H3. Had a pretty good oil leak from the valve cover gasket so figured id swap it out when she came home for spring break.

got everything put back together and now I have a crank no run situation.

battery was removed and reinstalled to make access to the manifold easier.

no codes on scanner.
i pulled each sensor connector for a cycle to make sure the lack of a connection would create code each one displayed a code but nothing when all are connected.

The security light is solid not flashing

checked the fuses 3 and 25 both good and swapped the relay around to no avail.

pulled one coil and checked for spark and that was good.

it tries to start when I spray carb cleaner through throttle body so I took it back apart and found some pinched wires at the the injector harness that were grounding out the common lead so that was repaired and put back together. And it still cranks without starting.
about to go out again and see if the plugs are wet.

been at it for two days now and I’m lost
anyone have any ideas?
 
Old Mar 22, 2025 | 10:38 AM
  #2  
Coronetkevin's Avatar
Thread Starter
|
Junior Member
Joined: Jul 2019
Posts: 7
From: Ocala fl
Default Update

So I’m looking at the injector harness and I’m not seeing any power to the injector harness when the key is in the on position.
My understanding is that the power is on constant with the ignition being in the on position and the pulse signal is the ground to open the injector.
looking at the diagram for the PCM I see the injector signal wires but nothing specifying the positive power so I’m assuming it comes from the ignition itself?
 
Old Mar 22, 2025 | 12:35 PM
  #3  
H2-SUT's Avatar
Senior Member
Joined: Apr 2019
Posts: 854
From: Albuquerque NM
Default

My guess is there is a fuse issue for the injectors/ECM. Take a look in the under hood fuse panel above the LF wheel well. Specifically fuses: 17, 21, 22, 23, and 33.
Otherwise if you don't have another compromised injector wire I would lean towards an issue with the ECM. The only other thing that comes to mind is the security circuit.

 
Old Mar 22, 2025 | 01:36 PM
  #4  
Coronetkevin's Avatar
Thread Starter
|
Junior Member
Joined: Jul 2019
Posts: 7
From: Ocala fl
Default Blown fuse

Originally Posted by H2-SUT
My guess is there is a fuse issue for the injectors/ECM. Take a look in the under hood fuse panel above the LF wheel well. Specifically fuses: 17, 21, 22, 23, and 33.
Otherwise if you don't have another compromised injector wire I would lean towards an issue with the ECM. The only other thing that comes to mind is the security circuit.
so it looks like the fuse for the injectors was blown.
got that swapped out and it almost started.

now suddenly I’m getting a P0230 code and no fuel pressure whereas I had pressure the last two days.

if I jumper the fuel pump relay 30 to 87 the pump runs and the engine starts.

this is becoming annoying
 
Old Mar 22, 2025 | 03:50 PM
  #5  
H2-SUT's Avatar
Senior Member
Joined: Apr 2019
Posts: 854
From: Albuquerque NM
Default

Check fuse 62
 
Old Mar 22, 2025 | 06:13 PM
  #6  
hummerz's Avatar
Senior Member
Joined: Jul 2012
Posts: 9,014
From: C-Town
Default

CHECK-> INSPECT ENGINE WIRING+CONNECTORS!


 
Old Mar 27, 2025 | 05:17 PM
  #7  
Doc Olds's Avatar
Super Moderator
Joined: Jul 2007
Posts: 13,101
From: Boat Town USA MI
Default

Any update?
 
Old Apr 10, 2025 | 01:44 PM
  #8  
H2-SUT's Avatar
Senior Member
Joined: Apr 2019
Posts: 854
From: Albuquerque NM
Default

Guess he either fixed it, gave up or burned it. lol
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Farryn Fodge
Hummer H3
9
May 26, 2021 11:24 AM
Raffi76
PRIVATE For Sale / Trade Classifieds
26
Feb 18, 2015 03:20 PM
94sam126
PRIVATE For Sale / Trade Classifieds
13
Nov 6, 2014 11:37 AM
Songman
PRIVATE For Sale / Trade Classifieds
27
Feb 16, 2014 11:42 AM




All times are GMT -5. The time now is 01:21 PM.