GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 5 of 5
  1. #1

    Default PLEASE HELP !! DTC P0300 02 sonoma 4.3L

    Hello Everyone,
    I have a 2002 GMC Sonoma 4.3L VIN W. It has roughly 130,000 miles on it. Im getting DTC P0300 Random multiple cylinder misfire. I have done everything that I can think of. Here is a list of the things I have already replaced:
    - Plugs & Plug Wires
    - Distributor
    - Distributor Cap
    - Rotor Button
    - Ignition Control Module
    - Ignition Coil
    - Crank Shaft Position Sensor
    - Fuel Pressure Regulator
    - I also took the truck to a GMC dealership and they put a GM Tech 2 on it and tested the injectors and they checked out fine.
    - Also did a Fuel Pressure Test
    - Checked for vaccum leaks

    I am beyond stumped. The only thing I can think of that is left to replace could be the ECM/PCM. If anyone has seen or heard of this and has in info that they can pass along it would be very much appreciated. I forgot to mention the truck doesn't really misfire at idle only when driving. I hooked it up to a MAC OBD II scanner and monitored it. Every time its the same thing cylinders 1 & 4 are almost dead. Thanks so much for any help.

  2. #2

    Default

    Quote Originally Posted by BLOWOUT View Post
    Hello Everyone,
    I have a 2002 GMC Sonoma 4.3L VIN W. It has roughly 130,000 miles on it. Im getting DTC P0300 Random multiple cylinder misfire. I have done everything that I can think of. Here is a list of the things I have already replaced:
    - Plugs & Plug Wires
    - Distributor
    - Distributor Cap
    - Rotor Button
    - Ignition Control Module
    - Ignition Coil
    - Crank Shaft Position Sensor
    - Fuel Pressure Regulator
    - I also took the truck to a GMC dealership and they put a GM Tech 2 on it and tested the injectors and they checked out fine.
    - Also did a Fuel Pressure Test
    - Checked for vaccum leaks

    I am beyond stumped. The only thing I can think of that is left to replace could be the ECM/PCM. If anyone has seen or heard of this and has in info that they can pass along it would be very much appreciated. I forgot to mention the truck doesn't really misfire at idle only when driving. I hooked it up to a MAC OBD II scanner and monitored it. Every time its the same thing cylinders 1 & 4 are almost dead. Thanks so much for any help.

    This is a general guide:

    http://www.obd-codes.com/p0300

    From looking around google, it could be an issue with a spark plug misfiring. I would check the plugs and cables (again). If you know someone with a diagnostic tool, see if they can find out which cylindar is mis firing.

  3. #3

    Default

    Are you losing coolant over time?
    "It went together didn't it? Well then there has to be a way to take it apart!" - Me.

    Check out my image gallery HERE.



    "The true measure of a man is how he treats someone who can do him absolutely no good." ~Samuel Johnson (1709-1784)

  4. #4

    Default

    My roommate has an OBD II scanner and its cylinders 1 & 4.

    - - - Updated - - -

    MOOGVO I really havent checked to see if im loosing coolant but i will check it and get back to you thanks

  5. #5

    Default

    My coolant levels appear to be fine.

Similar Threads

  1. Replies: 0
    Last: 05-27-2012, 07:40 AM
  2. Chevrolet : S-10 s10 sonoma pro street drag racing s 10 sonoma truck
    By ChevyFan in forum Chevy Trucks For Sale eBay
    Replies: 0
    Last: 08-12-2011, 05:40 AM
  3. Chevrolet : S-10 s10 sonoma pro street drag racing s 10 sonoma truck
    By ChevyFan in forum Chevy Trucks For Sale eBay
    Replies: 0
    Last: 07-22-2011, 06:40 AM
  4. Sonoma Chevrolet Review - Sonoma, CA
    By Chevy Dealer Reviews in forum Car Dealer Reviews
    Replies: 0
    Last: 01-08-2011, 08:08 PM
  5. Replies: 0
    Last: 01-10-2010, 10:20 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •