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Discussion Starter · #1 ·
Had a P0302 reading on my ‘02 4.2. Replaced #2 coil and all spark plugs. Plug in #2 was definitely darker but not wet. Reset computer. Now have P0300 and a more noticeable miss than I did before. Checked each cylinder by pulling coil connection for each cylinder individually. When I pulled 1,2,3 individually motor nearly died as it should ( I assume by reading other posts). When I pulled 4,5,6 individually there was no change. I have checked the plug connection on 4,5,6That does not seem to matter.
Also changed fuel pressure regulator as there was gas in the resonator box coming from the line that connects to box. That problem has been resolved but the idle now jumps from 1390 to 500 and never did prior.
Any ideas?
 

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Welcome to the Forum!

Go back and pull all the coils off the spark plugs, and reseat them to make sure that the coiled spring securely seats on each spark plug.

As far as the idle jumping, you first need to check and make sure that the PCV system is clean, and then clean the throttle body.

Please refer to this video on the PCV system before you go about cleaning it or the throttle body:


Here is a thread on how to properly clean your throttle body - BUT FIRST DO NOT DISCONNECT ANY BATTERY CABLES - JUST REMOVE THE APPROPRIATE FUSES FROM THE UNDERHOOD FUSE BOX! If you disconnect the battery you risk breaking the HVAC actuators when you reattach the battery cables and replacing the HVAC actuators is not a job for the inexperienced!!!!!!


After you've finished, please report back in case if the P0300 persists.

Good Luck!
 

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Discussion Starter · #3 ·
Welcome to the Forum!

Go back and pull all the coils off the spark plugs, and reseat them to make sure that the coiled spring securely seats on each spark plug.

As far as the idle jumping, you first need to check and make sure that the PCV system is clean, and then clean the throttle body.

Please refer to this video on the PCV system before you go about cleaning it or the throttle body:


Here is a thread on how to properly clean your throttle body - BUT FIRST DO NOT DISCONNECT ANY BATTERY CABLES - JUST REMOVE THE APPROPRIATE FUSES FROM THE UNDERHOOD FUSE BOX! If you disconnect the battery you risk breaking the HVAC actuators when you reattach the battery cables and replacing the HVAC actuators is not a job for the inexperienced!!!!!!


After you've finished, please report back in case if the P0300 persists.

Good Luck!
Thank you very much. You were right! I was just being careless with installation. Once I took #6 off and realized the dielectric grease looked the same as when I first applied it I realized I was the problem. After correcting the coil issue, the idle issue went away. Thanks for your help.
 

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Happy to have been of assistance! Glad it was an easy fix!
 

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Had a P0302 reading on my ‘02 4.2. Replaced #2 coil and all spark plugs. Plug in #2 was definitely darker but not wet. Reset computer. Now have P0300 and a more noticeable miss than I did before. Checked each cylinder by pulling coil connection for each cylinder individually. When I pulled 1,2,3 individually motor nearly died as it should ( I assume by reading other posts). When I pulled 4,5,6 individually there was no change. I have checked the plug connection on 4,5,6That does not seem to matter.
Also changed fuel pressure regulator as there was gas in the resonator box coming from the line that connects to box. That problem has been resolved but the idle now jumps from 1390 to 500 and never did prior.
Any ideas?
I noticed you performed a small expiative in your original post.

That would only turn people OFF and they'd not then want to help you. We are here because we want to correct our vehicles idiosyncrasies, not lambaste the owners nor impugn their intelligence.

For that --- I say: Thanks!
 

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Discussion Starter · #6 ·
I noticed you performed a small expiative in your original post.

That would only turn people OFF and they'd not then want to help you. We are here because we want to correct our vehicles idiosyncrasies, not lambaste the owners nor impugn their intelligence.

For that --- I say: Thanks!
Are you sure you have the correct post? I have re read my original post twice and have found no expletives. If there was it was surely due to something being spelled wrong. I apologize for whatever you think you read and rest assured I only offer the same respect i seek from others. Maybe some one was questioning my intelligence and it has since been removed.
Have a nice day.
 

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You might be right ... I was using a cellphone with a postage stamp small screen and might have clicked on you when I wanted a different OP.

You arent the guy I was after. Very sorry.
 

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PS ... I even like your dog.

For the record, it wasn't an expletive.....

The act of expiation is a way to atone for something you did that was wrong. It was originally used in a religious context, with expiation the way a person could gain forgiveness from a god.

If you've ever tried to make up for something you did wrong, then you understand the notion of expiation. The idea of atonement stretches across all religions, from Judaism’s Yom Kippur (Day of Atonement) to perhaps the most famous example of expiation, the Christian doctrine of Christ dying to absolve the world's sins. You definitely don't need to be religious to seek expiation. People who commit crimes and even make small mistakes seek expiation every day.

I thought you had retracted a statement before it got out too far and you had edited it quickly when you realized you had stepped on your tongue......
.... but it wasn't you. My fault .......
 

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Discussion Starter · #9 ·
You might be right ... I was using a cellphone with a postage stamp small screen and might have clicked on you when I wanted a different OP.

You arent the guy I was after. Very sorry.
mm
PS ... I even like your dog.
Thanks… that’s what happens when I let my 8 year old play on my phone. End up with my dog as my profile pic on Google. Of course I can’t figure out how to change it. Hahahaha
 
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