Codes P300 & P200 ????? MisFires?? Fuel injectors???
 

About a month and half ago my engine light pop up. I took it to autozone and they gave me these codes P300 & P200. then a couple days later when i was driving my 2003 Hummer H2, the engine light started to blink. So i took it to the dealership and they told me that my spark plugs were bad and fuel injectors need to replaced. Price of them to replace all of that came to $1500.. So i said hell no and took it home. I was home for about 30 min. then decided to replace the spark plugs and wire cords myself. As i was leaving to go to my buddy's house to replace them.. i notice my Engine light was off.. So i thought it was weird.. but i still expected the engine light to turn on.. never did. When i got to my buddy's house we replaced all 8 spark plugs and everything was fine for a couple weeks.. then the same things started happening slowly.. went to autozone again and pulled the same codes. i just passed 100,000 miles too. Now heres my question.. How many fuel injectors are in my hummer? and are they easy to replace? are there anything else i should replace in the process like the fuel filter or fuel pump? or should i just pay the dealership that $1500? Thanks!

did you change the wires when you changed the plugs?

if not.... do it....

BTW.... injectors are really easy on the H2...

yea I changed the wires too when I changed the spark plugs.. you know how many injectors the H2 has? cuz I know there about $120 a pop..

I just pulled out my "OBDII" Trouble code chart ... "P0200"... Is Injector Circuit. "P0300" is Random/Multipie Cyl Misfire Detected

Injector Circuit..Means.... Wireing as well as injectors..... So..I would chech the wiring in and around the triggering Circuit that fires the injectors. Thier are Boo Coo connectors in and around that wireing Harness. Could be oxidized or wet and just need some contact cleaner on the juntion connectors.

I would eliminate that first.. CYl misfire"P0300" is a result of the injector not firing.

Hope this helps..
Stumpy

is there anything I should worry about before cleaning those wires? and what kind of cleaning material should I use to clean those wires?

Your engine is a V-8 so there would be 8 injectors....

and anybody that told you $120 for the injectors should be shot.....

they are only a little over $30 each.... Hummer H2 Parts and Accessories

Once you get them apart.. you can use what I have used in the Pro Audio Industy for cleaning Show Mix Consoles... This is the stuff One 5.5 oz can is pleanty.. It carries a Heffty Price... Check it out here..

DeoxIT® D-Series

Do some research around this site and you will see that they make some special Gack for the Audio industry for treating Silver flashed and Gold Flashed contacts.

Hey there just read up on your problem with you h2, i had the same problem with my 2003 h2 changed wire spark plugs and all 8 engine coil packs, i still have the engine light come on, ive notice it flashes when i get to about 40 miles an hour, not sure if its my injectors, any can help would be very appreciated.

been through all this myself its the cats blocked