5.3 rich bank 2 p0175 p0300 p0304

[claypoolxx]

Hi.  I've been having some trouble with my new to me 2006 avalanche.  I know this is a silverado forum, but I've found more info here than the avalanche forum, so I hope its OK to ask.

 

Its a 2006 avalanche LT 1500 flex fuel.  It came with a new fuel pump and brake lines so I thought I was good.

 

I have been trouble shooting a p0175 p0300 p0304 codes.  

 

I checked the plugs and cylinder 4 was wet with fuel.

 

I replaced plugs and wires.  (I already had them)

 

I looked at the injector and didn't see any obvious signs of issues.  So I switched the injector from cylinder 4 with cylinder 2.  My thought is that if the plug for cylinder 2 becomes wet then the injector is the problem.  How long would I have to run the truck to see issues with the plug do you think?

 

If cylinder 4 is still wet then I'm thinking the coil is the issue.

 

Am I correct in my thinking?  Is there something I'm missing?  

 

Thanks for any guidance  

[txab]

Swap the suspect coil with the coil next to it and see if the issue follows it.

 

 

[claypoolxx]

I just switched the coil with a different cylinder than I switched the injector.  So if the problem moves I know what to replace.  BUT what if the problem stays in the same cylinder?  Where do I go next?

[sefiroxx]

Coil: check with a timing light that it is working
Spark plug: check boot area for any scorching to see if it is shorting to the engine
Fuel injector: a) use noid light to verify power to injector b) use mechanics stethoscope to verify the injector is opening/closing
Cylinder: compression test to verify valves and cylinder rings are operating correctly.

[claypoolxx]

I attempted to take the truck to work today.  I wanted to see if where the wet spark plug was would change.  It ran very rough.  If I gave it much gas at all the check engine light would flash, which never happened before.  Before it would be hard to tell if something was wrong, a slight stumble while at idle.  Now it is much worse.  I can bring it to my buddy with a scanner this weekend, but does this mean anything to anyone?

 

Also, it seemed to idle the same when I just moved the injector.  I went out later to switch the coil, but didn't start the truck again till this morning.  Could a bad harness lead kill the coil and now that I switched it I have two cylinders down?

 

 

 

SERFIROXX:  I don't have most of those things, but I am off of work this coming week so I can buy/borrow them.  The plug boot didn't look any different than the others though.  

 

This truck was just meant to tow my boat locally and some home depot runs.  I don't think I've put 1000 miles on it in the year I've had it.  I figured if I could get just another 10,000 fairly trouble free miles out of it, it would last a lifetime for me.  I take it to work once every other week in the winter to not let it sit too much, so I don't think the gas is an issue.