expert opinion needed
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expert opinion needed
I changed the plugs in my 01 expy 5.4l Friday and here is pic of the plugs that come out, these NGK plugs were installed about a year ago.
I have been having problems with rough idle and the truck lacking low end power. Now changing the has helped a little in the power, but not much. the rough idle is still there.
I have replaced the PVC hose and cleaned the IAC and MAF along with the TB and EGR port. I was needing some imput on what are the cause of the plugs to foul like they have.
there are no codes on the truck, but my LTFT on bank 1 is 10.2 and bank 2 is 6.8 at idle and bank 1 6.2 and bank 2 0 at 2500 RPMs if that helps.
I have been having problems with rough idle and the truck lacking low end power. Now changing the has helped a little in the power, but not much. the rough idle is still there.
I have replaced the PVC hose and cleaned the IAC and MAF along with the TB and EGR port. I was needing some imput on what are the cause of the plugs to foul like they have.
there are no codes on the truck, but my LTFT on bank 1 is 10.2 and bank 2 is 6.8 at idle and bank 1 6.2 and bank 2 0 at 2500 RPMs if that helps.
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To me it looks like the top one on the left, the 2 on the top right and the bottom right one might have issues with the COP for their cylinders. (Hopefully you recorded which cylinder each plug came out of.) This might be a simple case of the rubber boot for the COP leaking spark to the side of the plug well, resulting in a weak spark at each of the plug's electrodes.
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I don't know the exact cylinder they came off of, but I did notice that several COP had some hairline cracks on the bottom, just back of the arrow. I'm not certain they are cracks or just part of the molding, cause they are all in the same area. I did replace one of the COP cause it had a bulging area in the same place the others looked cracked. How could I check to see if they are cracked and not operating properly
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The only way to inspect them is to pull them out. Then bend, squeeze, and twist the rubber boots to see if any cracks show up. Alternately, you could just buy a set off eBay for $80 and swap them all out and be done with it.
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It's difficult to make any sort of reliable test on the COPs without a scope. All I do is start the engine and one at a time disconnect the 2-wire connector going to each of the COPs. When you find one (or more) that when unplugged don't affect the way the engine runs, then you've found a problematic cylinder. FYI, disconnecting the 2-wire connectors will turn on the CEL and throw a code. The code will self-clear after the COP is reconnected and the key goes off then on.
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I have done that test and everyone of the coils made the engine miss fire. I've done the injectors the same way.
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What gap did you use?
For one I would not run the NGK's. Autolites would be my choice.
I tried the Ebay COP, the ones for under 100 for all eight, lasted just over a year before they started to give out. Then I found on ebay someone selling factory COP for $140 or there about. Basically they came off crate motors and sells them. The crate motor was started with them on to make sure the motor runs and then they were taking off and sold on ebay. Very happy with them so far.
For one I would not run the NGK's. Autolites would be my choice.
I tried the Ebay COP, the ones for under 100 for all eight, lasted just over a year before they started to give out. Then I found on ebay someone selling factory COP for $140 or there about. Basically they came off crate motors and sells them. The crate motor was started with them on to make sure the motor runs and then they were taking off and sold on ebay. Very happy with them so far.
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I'm at a complete loss to why this truck is slightly missing at idle and lacks some low end power. I've been told by several people that its more than likely a vacuum leak, but I have tried to find it using Carb cleaner and starter fluid, even a propane torch. I have replaced the injector prongs and all the TB gaskets and the pcv hose. I cant find a leak anywhere
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Good deal, from the picture they look bigger then that.
The only other option would be the COP. When I replaced mine they were not throwing a code at all. First I replaced all the plugs then went after the COP.
Does it ping? I run 87 in mine and when the COP were on the way out (EBay) the motor started to ping bad. Replaced them with factory COP and the ping went away.
The other would be heat related as things warm up does it get worst?
The starter fluid is a good check to use for a leak for sure. If you did not find it with that it's not a leak.
The only other option would be the COP. When I replaced mine they were not throwing a code at all. First I replaced all the plugs then went after the COP.
Does it ping? I run 87 in mine and when the COP were on the way out (EBay) the motor started to ping bad. Replaced them with factory COP and the ping went away.
The other would be heat related as things warm up does it get worst?
The starter fluid is a good check to use for a leak for sure. If you did not find it with that it's not a leak.
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its doesnt ping. I also run 87. not really on the heat up part. It's just a slight miss. you can feel the engine shake a little and hear it in the exhaust at idle, but its very slight, just annoying
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