pmgm

iTrader: (5)

Ok , Hello first of all. I have a 06 silvy 6.0 and I have been getting a po300 check engine code. I thought maybe it needed spark plugs and wires so I changed them. My truck has about 66.xxx miles on it and has always ran good know I have this code. I have not driven it for a while because I would like to figure out what is causing this problem. I had the the engine scanned with a snapon scanner and real time showed that the #1 cylinder was miss firing alot all the cylinders showed a history of misfire but the #1 was alot worse. I even thought it might have had a bad coil so I swapped it out with no change. There is a slight miss at idle but it goes away as you get going. Winter is coming and I have to be able to drive my truck. I have been doing alot of reading and some have had similar problems that suggest cam and lifter failure. I dont have time to give money away to the dealer. Trucks out is out of warrenty but I can work on it myself if I have to. If the cam is bad what all will have to be done and also if I replace it should I go stock or upgrade it? Are there any other tests I can run?

Any help would be appreciated..

06 Silverado Hd 6.0/4l80 4x4...
Thanks
Pernell

mecanicman

Swap the #1 injector to another cylinder and see if the problem follows. Plugged injectors are far more common/likely then camshaft failure. You can just do an induction flush alternately. Not just a can of stuff in the tank, an actual induction flush.

grey matter 04

iTrader: (9)

if it happens to be a bad injector i have 2 sets of stock injectors for sale

lady3bglover

iTrader: (3)

Found something the the GM Forum that may help too. Start at post#2.
Help With P0300 03 2500hd 6.0 - GM-Trucks.com

Lisa

pmgm

iTrader: (5)

Thanks for the info... I will take a look at it...

j_schwaa

Not to go off topic, but I have a 6.0 I swapped in. It was originally a 4.8 5speed manual. My brother (who did the swap) told me that trucks with manuals had bigger injectors. I just want to know what the injector sizes are for the 4.8 auto, 4.8 manual, and 6.0. Thanks!

2.6KB

i was fighting this same problem #1 and #4 1 being the must i did everthing u did no change. Finally i swapped injector and the miss fire followed the injector so i sent mine back to racetronix to be cleaned and serviced. Flushed my fuel rails and hose back to the factory filter and put in a new fuel filter. Just got it all back together yesterday and no miss fires.

lady3bglover

iTrader: (3)

Since I'm mid-swap as we speak, from 5.3 to 6.0 you should know there is a chg in the size of the injector. I'm going from stock(24# ?) to 42#. Here's the trick. You need to make sure that your rails, harness, and injectors are compatible or you will more than likely end up with a conflict. B/c I've set a budget, changing my rails was not planned. I did however budget for the harness. With my new injectors I'm able to keep both rails and harness stock. Someday down the road I'd like to not only swap both along with a FAST intake.

Sorry to be long winded.

pmgm

iTrader: (5)

Ok.. No more po300 now im getting a po200 code... Im going to check injectors out next...