No, he said the wires....plug wires.
Spark plug issues!!! - SOLVED
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- 2004 tahoe tahoe
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Bear in mind.....#1 is at front on driver's side and #2 is at front on passenger side. #7 is at back on driver's side and #8 is at back on passenger side. Basically all corners
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cmyoung2007
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Ahhh, okay. Odds on driver side, and even on passenger side.
SPARK PLUG WIRES
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cmyoung2007
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Yeah, I know that now. It didn’t click in my mind right at that moment.
if the misfires change to 7&8 then you can pretty much call it bad wire set
the chances of having 6 bad coils is pretty freaking slim
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cmyoung2007
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I can tell you the misfire numbers are way lower than what they were to begin with after changing to ngk and you could hear the misfires before, but now you can’t. I will swap the wires after I get off work.
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One and two are the ones that misfire the most.
It works; on mine I had to download it. If the misfire counts are that low (<10) I wouldn't worry about them.
Having said that, #1 #4 & #5 are the ones that show a couple in the cycle. If you're concerned about those, swap the plug wire, coil, and spark plug one at a time with a better cylinder to see if the misfire follows. One piece at a time, then test; write down test results so you don't get confused about what's been changed.
EDIT: you could also have other issues causing this like fuel pressure, skewed fuel trims, but it doesn't look too bad to me.
Having said that, #1 #4 & #5 are the ones that show a couple in the cycle. If you're concerned about those, swap the plug wire, coil, and spark plug one at a time with a better cylinder to see if the misfire follows. One piece at a time, then test; write down test results so you don't get confused about what's been changed.
EDIT: you could also have other issues causing this like fuel pressure, skewed fuel trims, but it doesn't look too bad to me.
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cmyoung2007
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It still makes a misfiring code come on as pending/stored. I’ve been dealing with the check engine light for a couple days now on that part.
If it hasn't been done do a CASE relearn with a bidirectional scanner, just to rule it out. That correlates the crank sensor signal to the cam sensor signal, and that can cause the P0300 code.
If that fails, pull some more data.
MAF reading in g/sec at hot idle (also show rpm).
Do a fuel pressure test with the engine running (possible fuel pressure regulator issue). Rent a fuel pressure kit from your auto parts store.
Short- and long-term fuel trims, at hot idle and at 1800 or 2000 rpm.
Sometimes these will expose other problems that can cause misfires.
MAF reading in g/sec at hot idle (also show rpm).
Do a fuel pressure test with the engine running (possible fuel pressure regulator issue). Rent a fuel pressure kit from your auto parts store.
Short- and long-term fuel trims, at hot idle and at 1800 or 2000 rpm.
Sometimes these will expose other problems that can cause misfires.
Agree, clean the MAF. Did you have the air snorkel off the throttle body? If you did, you did not say so. Make sure it is seated properly and tight.
I also agree with @Fless about the misfire counts. That is no big deal, IMO, based on what I saw. Can you show a video of the fuel trims?
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cmyoung2007
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If you are talking about the connector, to the right of the power steering pump reservoir cap and to the left of the red possitive cable box, that is the coolant temp sender and connector. IIRC. It is always there on the older 5.7 engines. I believe it is still the same. There is a coolant temp sensor up near the thermostat housing and that is for engine temp info to the computer and the sender, in your pic, is for the dash cluster gauge.Can anybody tell me what the electrical connector below the valve cover attached to the side of the engine block is for? It’s the electrical connector right under the holding post for the battery + boxLog In - pdfFiller
Can anybody tell me what the electrical connector below the valve cover attached to the side of the engine block is for? It’s the electrical connector right under the holding post for the battery + boxLog In - pdfFiller
You can post jpeg and png pics directly into a post; that makes it easier on the members to see them right away and not have to go get them.
Videos are different: they need to be hosted somewhere else and the link put into the post.
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cmyoung2007
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Issue is fixed! It was the fuel pump!
How did you diagnose it? Care to share fuel pressure readings before and after?
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