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 10 of 10
  1. #1
    Jr. Apprentice
    Join Date
    Sep 2009
    Location
    From Ohio / Live in Texas
    Posts
    15

    Default Sluggish 4.3 V6 *Desperate*

    Title says it all. Here is the history.
    I had been having trouble getting my truck to start. 1997 Chevy Cheyenne 4.3 V6.
    I forget the codes but they read "lean"
    I changed my fuel pressure regulator on Friday 10/5/12
    At that time I decided to clean out my EGR valve.
    --
    upon start up it ran terrible. Before it was just a hard time starting it. Now it runs pretty bad.
    I assumed I killed the EGR valve when I cleaned it so I bought a new one. Same problem.
    When I attempted to check the plugs, I broke a plug wire. So it has new plugs and wires.
    Today I stripped everything back down to the fuel spider and fuel pressure regulator to check for leaks. Figured I knocked something loose maybe. No leaks. Everything was dry.
    Put everything back together, crossed my fingers and it still runs rough.
    I took it on a trip. The truck idles fine. When I accelerate it bogs down. If I try to rev the engine it bogs down. Even with cruise control on climbing a hill it bogs down.
    ---
    Summary:
    New
    Fuel pressure regulator
    EGR valve
    plugs and wires

    Runs very sluggish.

  2. #2

    Default

    Double check that you did not cross wires when changing them. I would change the distributor cap and rotor also. What about the fuel filter? has that been changed? I would also change that.

    1995 Silverado 4x4
    6" BDS Suspension Lift-3" Body Lift-Add A Leaf in rear -Trailmaster SSV Shocks-Duel Steering Stabilizer Kit -AirAid Cold air intake-
    4.56 Gears with Detroit Auburn Locker-Pro-Comp Traction Bars with duel shocks-Aluminum Skid Plate Kit-38.5" x 16.5" Mickey Thompson Baja Claws-Constant Dropping fuel gauge

    2005 Yukon XL Jet Power Programmer, Bilstein Shocks, Bilstein rear springs, Helwig Anti-sway bars, EGR Window Visors, EGR Hood Shield, Denali Headlights, Headlight harness upgrade, GE NightHawk Bulbs, White Night Rear lighting system, Russell Braided SS brake lines, PowerStop Brake pads, PowerStop cross drilled and Slotted Rotors, http://www.gmtruckclub.com/forum/sho...5-GMC-Yukon-XL
    2002 Silverado ext cab 2wd (Sold)
    2003 Yukon XL (Totaled)

  3. #3
    Jr. Apprentice
    Join Date
    Sep 2009
    Location
    From Ohio / Live in Texas
    Posts
    15

    Default

    I posted and it didnt take,
    I have re-checked the plug wires many times.
    I forgot to mention that I changed the fuel filter last week. (tunnel vision here)
    I was reading last night after I posted here that this is classic fuel pump going out. Does that make since?

  4. #4

    Default

    Quote Originally Posted by Pikey View Post
    Double check that you did not cross wires when changing them. I would change the distributor cap and rotor also.
    And the air filter

    Quote Originally Posted by bigdigv65 View Post
    I was reading last night after I posted here that this is classic fuel pump going out. Does that make since?
    Maybe, it has been my experience that a fuel pump will work fine, shut off the truck and it will not start ---- pump failed. I have never had one act bad before it failed.

    But, a pressure gauge will give you an instant check.

    While your at it, a compression check might be a good idea.
    Ray

    '09 Avalanche LTZ - Black
    '05 Envoy XL (sold)

  5. #5
    Jr. Apprentice
    Join Date
    Sep 2009
    Location
    From Ohio / Live in Texas
    Posts
    15

    Default

    I'm running out of funds here. Is there any way to check the air filter before buying a new one? Can I just take it out and run the truck without it for a few minutes? I don't have a fuel pressure gauge. I'm about to get out there and pull the inlet side of the fuel line to the filter and see what kind of stream I have visually.

  6. #6
    Jr. Apprentice
    Join Date
    Sep 2009
    Location
    From Ohio / Live in Texas
    Posts
    15

    Default

    Sorry to double post. I didn't want to edit the other pot that some may have read.
    I disconnected the "air meter" on my intake tube right next to the air filter. It runs like a champ. No more sluggish acceleration or revving issues.
    ---
    Is it safe to say that air meter is bad? I hope that's not a stupid question. Been a very long three days.
    Also, I still have cold start issues? I had to crank my truck 4 times before it fired up this morning. Could this air meter cause that as well?

  7. #7

    Default

    The "Air meter" AKA Mass Air FLow sensor (MAF) could be bad, but what I find odd is I normally have problems with an engine running worse when you disconnect the MAF, some engines wont even start when it's disconnected. Doesnt mean it isnt the problem though.
    Do you know anyone that'll let you borrow a maf long enough to check the system?
    That check is certainly easier than what I was gonna recommend which is to look at the fuel spider, it's been known to be a problematic part on the 4.3.

  8. #8
    Jr. Apprentice
    Join Date
    Sep 2009
    Location
    From Ohio / Live in Texas
    Posts
    15

    Default

    I may have a friend or two that have this on their truck and may let me use it as a test. What scares me is the cost of it. Say I have an electrical problem that blows theirs too. Now I buy two. Does that make since or am I was over thinking this.
    I just drove it to a friends house. Drove fine to and from.

  9. #9
    Jr. Apprentice
    Join Date
    Sep 2009
    Location
    From Ohio / Live in Texas
    Posts
    15

    Default

    More testing today. I took the MAF out and cleaned it with a qtip and rubbing alcohol. I got a lot of dirt off of it.
    I plugged it in with the engine running and the engine's performance remained the same. However, when I plugged in the air temp sensor, I bogged down and backfired into the air filter box.
    I went to the parts store, took it out and tried to clean it. Same.
    I bought a new one, everything seems fine engine wise but it is or was running super rich. I won't know if this helps the cold start issue until tomorrow morning.

    Anyone had a heck of a time with an air temp sensor?

  10. #10
    Jr. Apprentice
    Join Date
    Sep 2009
    Location
    From Ohio / Live in Texas
    Posts
    15

    Default

    Update:
    It was ultimately the fuel pump. Tested pressure with the key on.....50 PSI. Pressure would bleed down to 10 PSI inside of 15 minutes. Running 40 PSI. Kind of surprised the truck started at all.
    I also found that the sluggish part to this was a dirty MAF and I replaced the air temp sensor by the filter. Air temp sensor had it running bad. Fuel pump made it hard to start cold.

Similar Threads

  1. 07 Silverado 5.3L feels sluggish
    By mah2496 in forum Performance & Fuel
    Replies: 12
    Last: 08-30-2010, 08:44 PM
  2. 2010 Silverado WOT Sluggish
    By Gatorfan71 in forum Performance & Fuel
    Replies: 5
    Last: 07-16-2010, 07:41 PM
  3. engine sluggish
    By jdog468 in forum General Chevy & GM Tech Questions
    Replies: 9
    Last: 04-06-2010, 02:07 PM
  4. sluggish website?
    By ChevyFan in forum Announcements & Feedback
    Replies: 4
    Last: 06-05-2007, 02:53 PM
  5. Desperate for help!!! Katrina messed up my Tahoe!
    By cheffernan in forum The Coffee Shop ~ Chit Chat
    Replies: 5
    Last: 09-02-2005, 09:33 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
  •