Misfire P0300 HELP

Asked by Jun 26, 2016 at 12:27 AM about the 2005 GMC Yukon SLE

Question type: Maintenance & Repair

So I got the P0300 code. I thought it was just a bad
coil so I replaced. Wasn't it. Did a tune up. Never
fixed it. So I pulled valve covers found #5 cyl to
have a bent push tube. Checked all of the others.
Number the only one. Replaced tried again still the
same. So I've replaced timing chain oil pump the
oil pick up o-ring. Map senors. At high idle it runs
fine. It won't stay running at all. I even replaced the
injector on #5 to.  I'm lost not sure we're to go or
what to do.

1 Answer

79,095

You may have some issues with the valve train, vacuum leaks need to be checked for, but why would a push rod be bent in the first place would be the question. P0300 CHEVROLET - Cylinder Misfire Detected Random Cylinders- Possible causes - Faulty spark plug (s) - Faulty ignition coil (s) - Clogged or faulty fuel injector (s) - Intake air leak - Fuel injectors harness is open or shorted - Fuel Injectors circuit poor electrical connection - Ignition coils harness is open or shorted - Ignition coils circuit poor electrical connection - Insufficient cylinders compression - Incorrect fuel pressure- The P0300 code means that a cylinder(s) is misfiring or is randomly misfiring. Start by checking for intake leaks, intake gaskets are common caused of multi-cylinder misfiring. If no leak are found the next step is to replace the spark plugs. If the problem persist more tests needs to be done to diagnose problem....

2 of 2 people found this helpful.

Your Answer

GMC Yukon Experts

  • #1
    clayduster71
    Reputation
    2,780
  • #2
    David Boccabello
    Reputation
    920
  • #3
    Drpsychmom
    Reputation
    750
View All

Related Models For Sale

Used Chevrolet Tahoe
818 Great Deals out of 39,847 listings starting at $1,900
Used Cadillac Escalade
283 Great Deals out of 12,102 listings starting at $2,995
Used GMC Yukon XL
294 Great Deals out of 13,310 listings starting at $1,750
Used Chevrolet Suburban
482 Great Deals out of 23,253 listings starting at $1,995
Used GMC Sierra 1500
1,106 Great Deals out of 61,547 listings starting at $1,295
Used Ford Expedition
489 Great Deals out of 20,069 listings starting at $2,388
Used Chevrolet Silverado 1500
2,725 Great Deals out of 156,636 listings starting at $1,000
Used Cadillac Escalade ESV
138 Great Deals out of 6,308 listings starting at $1,995
Used Ford F-150
3,016 Great Deals out of 229,513 listings starting at $1,300
Used Jeep Grand Cherokee
890 Great Deals out of 71,119 listings starting at $900
Used Ford Explorer
1,087 Great Deals out of 67,834 listings starting at $1,200
Used Dodge Durango
261 Great Deals out of 24,840 listings starting at $1,500
Used Toyota 4Runner
335 Great Deals out of 29,318 listings starting at $1,500
Used Nissan Armada
131 Great Deals out of 10,289 listings starting at $1,990

Used Cars For Sale

2018 GMC Yukon SLE For Sale
416 listings starting at $43,213
2017 GMC Yukon SLE For Sale
79 listings starting at $39,480
2016 GMC Yukon SLE For Sale
3 Great Deals out of 52 listings starting at $32,995
2015 GMC Yukon SLE For Sale
16 Great Deals out of 156 listings starting at $27,992
2014 GMC Yukon SLE For Sale
13 listings starting at $15,000

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.