• Welcome to H4O! For a reduced ad experience, please login or register with the forum.

2008 H3 Alpha (P0302 code)

AUSFEA

Probationary Member
Messages
4
Location
Temecula, CA
Have a 2008 H3Alpha, non Adventure Package. Threw service code P0302 indicating bad cylinder #2. Changed plugs, wires, and coils to no avail☹️. Looking for a knowledgeable mechanic and replacement 5.3L V8 engine in Southern California. Everything else on the truck is good condition. Has upgrades of dual exhaust, front brush guard, Gobi Stealth roof rack (sunroof version).
 

AUSFEA

Probationary Member
Messages
4
Location
Temecula, CA
TD-5, thanks for your reply. Forgot to mention, the engine is making a tapping sound from the cylinder, making me feel it’s a mechanical issue.
 

lfootmatt

Well-Known Member
Messages
136
Location
AZ
bad fuel injectors can lead to a lean knock condition. I wrecked my 3/4 ton Suburban's 8.1L that way. 60psi compression in that cylinder. The injector wasn't delivering enough fuel creating the lean condition that literally beat the rings off the cylinder.

How many miles are on your Alpha?

Happy New Year!

Matt
 

AUSFEA

Probationary Member
Messages
4
Location
Temecula, CA
bad fuel injectors can lead to a lean knock condition. I wrecked my 3/4 ton Suburban's 8.1L that way. 60psi compression in that cylinder. The injector wasn't delivering enough fuel creating the lean condition that literally beat the rings off the cylinder.

How many miles are on your Alpha?

Happy New Year!

Matt
Thanks Matt. I have approximately 135K on my 2008 H3 Alpha.
 

TD-5

Member
Messages
10
Location
BC Canada
You can try swapping the #2 injector with a different cylinder (say #7 cyl). If the noise follows the injector, then its faulty. If the noise you hear stays with cyl #2 then you will need to pull the valve cover & inspect rockers & valve movement. If one of the valves on #2 is moving less when rolling the engine over, compared to the others, there is a problem with the cam/lifter for that valve.
 
Top