I just picked up a 2001 2500HD with the LQ4. The truck was running fine until I actually paid for the truck and now it's throwing codes. It runs like crap when under load, but when I just cruise at say 45mph, the SES light turns off and the truck runs fine. I get the codes P0307 and P0332, cylinder #7 misfire and bank 2 knock sensor low impedience. It was an old oil field truck and they used gas out of a giant 500 gallon tank, and so it wasn't of very high quality. The truck made the trip from Amarillo to Houston fine, but now it's acting up, and I'm thinking it has something to do with the gas. I changed the fuel filter (planned to do it anyways) and the gas that came out the filter was nasty with dirt and other crap in it. I'm thinking perhaps a clogged injector, but I haven't had a chance to pull the spark plugs yet. If anyone else has any ideas, I'd definately appreciate it.

Tom

here are some pics: http://community.webshots.com/album/288559240YbCJpn

 

Hey Pal,
Email me with your codes and a description of the COMPLETE problem and I'll try to halp you out. Trust me, this is what I do for a living.
josh_evanz@hotmail.com

 

Will do, thanks .

Tom

 

Anyone have any ideas? How about any ideas of what I should replace for a tune-up (besides plugs, wires, etc. This is my first LSx based engine, so I'm kind of playing catch-up)? Thanks.

Tom

 

you need to remove the fuel rail and remove inj 7 and see if its plugged up with dirt, its common on field trucks to have dirt intrusion, if so i would change fuel filter, tap out injector and try to flush it with tec and gasoline mixture, it may not clear up and you may need to replace the injector, drive it for a couple hundred miles and change filter again, try to run good gas through it, the p0332 dtc is a knock sensor code, we have had alot of water intrusion into the senso hole and corroding it, it will set dtc and some driveability symptoms will be noticeable sometimes, to fix this you will need to replace the sensor and build a little wall of silicone aroun the grommet that seals the hole, most likely the knock sensor thats corroded is the back one.

 

Will do. I've already changed the fuel filter, and I plan to do it again in probably a month. I'll check the knock sensor and fuel injector. Thanks for the help .

Tom

 

I have some used stock injectors if you need them.

 

Sweet, I'll keep you in mind. This weeks been horrible on my time, so I'm hoping to get to work on this thing on Saturday, though it looks like I am probably going to have to work then too (too many people taking vacation at the same time ), so I'll let you know. Thanks for the help guys .

Tom