Misfire

10

Asked by Jun 05, 2016 at 02:53 AM about the 2004 Chevrolet Silverado 1500 Z71 Ext Cab Short Bed 4WD

Question type: Maintenance & Repair

I have a problem. My 2004 Chevy Silverado will
idle fine for about 30 seconds then all the sudden
my 6th cylinder only will start to misfire. I have
changed my Mass Air Flow sensor, switched out
the coil, switched out the spark plug and wire,
switched out fuel injectors, cleaned out fuel rails,
checked for fuel pressure (it's fine), and even
changed out my downstream O2 sensor in Bank 2.
If I turn the truck off and start it, it will idle just fine
and then again after about 30 seconds of idling it
will start to misfire in only the 6th cylinder. I need
some advice. Any and all help is appreciated!

6 Answers

246,165

What was the condition of the spark plug on cylinder #6? If you replaced the ignition and fuel injectors, the next step would be to do a leak down and cylinder pressure test to see if that #6 cylinder is lower than the other cylinders. Meaning a faulty head gasket or a valve problem. Good luck.

72,125

Should do a compression test on the cylinder, should be around 150 psi. and no lower than 120.

49,145

I agree with Rowefast, you either have a compression problem or an intake manifold leak at #6.

10

Spark plug in the 6th cylinder was just fine. It didn't seem wet like it was getting flooded or anything. We checked the compression in the 6th cylinder that misfires and compression was just fine.

10

Also if I put it in gear right after I start it, it won't misfire but it still seems to run sluggish. Thanks again for yalls help.

72,125

Sounds like you now have to dig deeper into the problem. Ideas I have at this time would be to check the power running to the coil, inspect the wire, check the voltage once she starts to miss-fire, make sure the ground are good. Also you may want to do a fuel bleed down test by hooking up a fuel pressure gauge to the Schrader valve up located up on the intake. Build up fuel pressure by cycling the key on, off, until fuel pressure builds up, should be 56 to 63 lbs. Turn the key off and watch the gauge, it should not drop in pressure more than 5 lbs. in 3 minutes. If it does, this indicates a leaky injector, line, or fuel regulator.

Your Answer

Add photo

Related Questions

  • Misfire 6 answers

    I have a problem. My 2004 Chevy Silverado will idle fine for about 30 seconds then all the sudden my 6th cylinder only will start to misfire. I have changed my Mass Air Flow sensor, switched out t...

    2004 Chevrolet Silverado 1500 Z71 Ext Cab Short Bed 4WD

    -

    Maintenance & Repair

  • Misfire 1 answer

    I found this car and she the auto parts store told her that she had a misfire what is that what does it mean how do you fix it is it expensive

    2003 Chevrolet Malibu

    -

    Maintenance & Repair

  • Misfire 1 answer

    Replaced distributor,distributor cap,spark plugs and wires but still has misfire what could be the problem

    1999 Chevrolet Suburban K1500 4WD

    -

    Maintenance & Repair

  • Misfire 2 answers

    I have a 1999 s10 4.3l vortec, it misses in cylinder 4, I have replaced the spark plug, and plug wire, but it continues to misfire, I am thinking I have a problem with the distributor cap or the w...

    1999 Chevrolet S-10 3 Dr LS Wide Stance 4WD Extended Cab SB

    -

    Maintenance & Repair

  • What would cause a misfire on #7 cylinder of a 2006 chev Silverado 4x4 with a 4.8 engine 1 answer

    Has a misfire on # 7 cylinder of my 2006 chev Silverado 4x4 with a 4.8 engine

    2006 Chevrolet Silverado 1500 Work Truck Ext Cab 4WD

    -

    Maintenance & Repair

Silverado 1500

Looking for a Used Silverado 1500 in your area?

CarGurus has 182,391 nationwide Silverado 1500 listings starting at $1,595.

ZIP:

Search Chevrolet Silverado 1500 Questions

Chevrolet Silverado 1500 Experts

#1 John Carson
John Carson
Reputation 2,410
#2 Rowefast
Rowefast
Reputation 1,950
#3 Silverado_owner_2006
Silverado_owner_2006
Reputation 1,650
View All

Related Models For Sale

Used GMC Sierra 1500
781 Great Deals out of 68,593 listings starting at $1,800
Used Ford F-150
2,134 Great Deals out of 195,043 listings starting at $290
Used Dodge Ram 1500
388 Great Deals out of 10,857 listings starting at $1,000
Used Chevrolet Silverado 2500HD
297 Great Deals out of 28,411 listings starting at $1,500
Used Toyota Tundra
460 Great Deals out of 34,672 listings starting at $2,500
Used Toyota Tacoma
515 Great Deals out of 43,078 listings starting at $1,995
Used Chevrolet Tahoe
578 Great Deals out of 32,785 listings starting at $1,500
Used Chevrolet Colorado
241 Great Deals out of 27,219 listings starting at $1,000
Used Ford F-250 Super Duty
319 Great Deals out of 44,669 listings starting at $1,450
Used Chevrolet Silverado 2500
12 Great Deals out of 244 listings starting at $3,900
Used Chevrolet Silverado 1500HD
12 Great Deals out of 277 listings starting at $3,995
Used Nissan Titan
166 Great Deals out of 18,975 listings starting at $3,000

Used Cars For Sale

2017 Chevrolet Silverado 1500 For Sale
285 Great Deals out of 127,714 listings starting at $20,589
2016 Chevrolet Silverado 1500 For Sale
130 Great Deals out of 5,682 listings starting at $18,967
2015 Chevrolet Silverado 1500 For Sale
228 Great Deals out of 8,306 listings starting at $12,950
2014 Chevrolet Silverado 1500 For Sale
248 Great Deals out of 10,206 listings starting at $9,798
2013 Chevrolet Silverado 1500 For Sale
166 Great Deals out of 4,926 listings starting at $7,988

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.