98z71 5.7 multiple misfire P0300 fouling 1 3 5 7 plugs with gas what causes ths

Asked by Jan 05, 2016 at 12:59 PM about the 1998 Chevrolet C/K 1500 Cheyenne Standard Cab SB

Question type: Maintenance & Repair

9 Answers

27,105

only on that side... try and go up 2 heat ranges on that side,,,and / or first .. take some good pictures of those plugs and post them...

73,775

Possible causes po300:... - 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 Tech notes 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,

Replace plugs wires dis cap n rotor button still doing same thing

73,775

Check for vacuum leaks, that is a Vortec engine, intakes are prone to leak, check the bolts, there are only 8 of them, torque to 15 to 20 ft.lbs. They say 12 ft.lbs. but that is pretty light.

1 of 1 people found this helpful.

Check all that n leaks on intake

73,775

By chance did you use carburetor cleaner? If there is a vacuum leak spraying the carb cleaner would make the rpm rise. If still all good then you are going to have to dig into it to find the problem. How many miles on her? Compression test may be in order. After that or you could do first is get the coils checked. I would check the electrical connections to the injectors also.

Compression is good has little over 100000 on it have checked ll connection s injection all good fuel pressure is correct

Only has the one coil pack could it cause it to misfire n foul plugs on one side

73,775

Well yes, that can be tested, I believe Auto Zone can. But I know I have looked on line on how to and what specs to look for when testing a coil, but you would need a volt ohm meter.

Your Answer

C/K 1500

Looking for a Used C/K 1500 in your area?

CarGurus has 846 nationwide C/K 1500 listings starting at $2,000.

ZIP:

Chevrolet C/K 1500 Experts

  • #1
    Andrew Olsen
    Reputation
    3,600
  • #2
    John Saffrahn
    Reputation
    2,570
  • #3
    Rowefast
    Reputation
    2,170
View All

Related Models For Sale

Used Chevrolet Silverado 1500
2,139 Great Deals out of 167,072 listings starting at $1,498
Used GMC Sierra 1500
889 Great Deals out of 65,336 listings starting at $1,995
Used Ford F-150
2,318 Great Deals out of 182,094 listings starting at $1,000
Used Chevrolet C/K 2500
198 listings starting at $6,495
Used Dodge Ram 1500
392 Great Deals out of 10,914 listings starting at $1,500
Used Chevrolet C/K 3500
229 listings starting at $4,999
Used Chevrolet Tahoe
664 Great Deals out of 39,392 listings starting at $1,000
Used Toyota Tacoma
604 Great Deals out of 42,670 listings starting at $1,500
Used Chevrolet Camaro
413 Great Deals out of 30,658 listings starting at $3,550
Used Chevrolet S-10
8 Great Deals out of 1,217 listings starting at $2,500

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.