bad engine knock! PLEASE HELP!!!

[geo1]

j cat,i enjoy reading youre input,to the po300,have you seen one go away?on own,my few expierences always needed a relearn,even after problems fixed,input helpful thanks

[j cat]

yes on my 2000 I had this glitch occur 2 X over the 13 years. In the oem shop manual it actually explains how this can occur with no failures.

If the engine has a sudden surge in torque it is possible that the timing sensors get out of position for a milli sec and then the p0300 will come on. then the check engine light will stay on for many start cycles before it resets. I twice had to manually reset this and no issues so far.

I never used the relearn . some have had to use the relearn when replacing the timing sensors but not all.

It seems that most times this is due to low fuel pressures/low fuel volume. weak pump ,regulator, or not replacing the fuel filters if installed.

[yeevveey211]

yes on my 2000 I had this glitch occur 2 X over the 13 years. In the oem shop manual it actually explains how this can occur with no failures.

If the engine has a sudden surge in torque it is possible that the timing sensors get out of position for a milli sec and then the p0300 will come on. then the check engine light will stay on for many start cycles before it resets. I twice had to manually reset this and no issues so far.

I never used the relearn . some have had to use the relearn when replacing the timing sensors but not all.

It seems that most times this is due to low fuel pressures/low fuel volume. weak pump ,regulator, or not replacing the fuel filters if installed.

does just the engine light show up for those start cycles or does still misfire?.

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i disconnected my battery and am going to battery test Tom . simple first. checked my plugs they are all fine Dosent look like they need to be replaced . I Have had no Time to work on her . I also am going to spark test all coil packs to see if hats the problem. I don't have a fuel pressure tester I wish I did to check the injectors .

[j cat]

does just the engine light show up for those start cycles or does still misfire?.

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i disconnected my battery and am going to battery test Tom . simple first. checked my plugs they are all fine Dosent look like they need to be replaced . I Have had no Time to work on her . I also am going to spark test all coil packs to see if hats the problem. I don't have a fuel pressure tester I wish I did to check the injectors .

auto zone / advance auto should have the pressure gages.

[geo1]

this is why i am here,my last po300 was solved with a relearn,but not before changing front knock sensor and pig tail harness,02 silverado 6.0 liter,constantly learning here!

[j cat]

this is why i am here,my last po300 was solved with a relearn,but not before changing front knock sensor and pig tail harness,02 silverado 6.0 liter,constantly learning here!

with the KS having a bad connection this would cause the timing to jump creating the 300 code. also this most always will produce the KS code .

washing the engine usually causes the KS issues. the upper intake was not properly sealed at the factory build. TSB states to seal the front and leave the rear open .

[yeevveey211]

with the KS having a bad connection this would cause the timing to jump creating the 300 code. also this most always will produce the KS code .

washing the engine usually causes the KS issues. the upper intake was not properly sealed at the factory build. TSB states to seal the front and leave the rear open .

u know I was thinking about that because up here in photo we only had once very nice day and I washed my truck before work and now it's snow gain son of a b**** I washed it before work and this happens the morning after

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so your saying take the intake manifold off and check the two knock sensors connections?

[j cat]

look between the upper and lower intake manifolds at the front of the engine . is the space sealed or open . if open a very good chance this is a problem.

I had rodents chew on the foam GM used causing this to be open slightly but I caught it before any damage was done.

I used a silicone based gasket sealer with a foam material . worked the pre cut/shaped foam first then applied sealer to foam and then installed for a very water proof flex gasket . then after the sealer set applied more sealer to the face of the gasket material . so far it is still perfect.

rodents dont like this stuff around here anyway.

[yeevveey211]

look between the upper and lower intake manifolds at the front of the engine . is the space sealed or open . if open a very good chance this is a problem.

I had rodents chew on the foam GM used causing this to be open slightly but I caught it before any damage was done.

I used a silicone based gasket sealer with a foam material . worked the pre cut/shaped foam first then applied sealer to foam and then installed for a very water proof flex gasket . then after the sealer set applied more sealer to the face of the gasket material . so far it is still perfect.

rodents dont like this stuff around here anyway.

had checked about half hour ago . no open spaces or gaps.
but since it's the only nice day for a week or so here I took advantage of it and checked a couple of things for my truck.
1. battery is good and has good cranking amps and at a solid state
2.hooked up computer it cleared the p300 code
3. still knocking . but have good spark through all cylinders
but I did find a little glitch here when I washed my truck the day before this happneed there is a leak through the weather stripping above the firewall. I took a couple pictures for ya guys

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sorry lts not turned. but you can see the bent weather stripping and I could see where the water when down on top if the motor.

[geo1]

thanks for tsb info,i left rear foam in,will remove asap,back to po300 on yees v rod,any symptoms?i had none,took a month before k.s. code came up

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good question,say the vehicle was parked down hill,would water wick thru from rear onto valley?