Misfire on #4 and 6. Truck is stranded in KY
10-06-2012, 01:40 PM
#11
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Yeah I know. I only was getting part of the story from my brother in law. They took everything off and charged him $100 for what they did. He took it to the dealer this morning that was close and they said it is the cat. They loosened the y pipe a little so that it can breather some and it is running 100 times better. Thanks for the info guys. He took it back to the guy who looked at it yesterday and told him and he said even if we fix the cat it will still have the misfire but once I get it back I can deal with it.
10-06-2012, 01:57 PM
#12
The misfire can be caused by the cat being clogged. When the exhaust has nowhere to go it backs up.
Let them fix the cat and see if still misfires. If it does, then check the basics. It might be as simple as a tune up if he put all the old parts back in like he said. Also some fuel injection cleaner would be a good idea. Excessive carbon buildup can occasionally cause misfires issues.
If not then check each component. If you don't have the equipment then swap the parts with the a good cylinder and see if it follows. If it does the part is bad. If not then you need to take it to someone with the proper equipment.
Good luck!!! keep us posted
Let them fix the cat and see if still misfires. If it does, then check the basics. It might be as simple as a tune up if he put all the old parts back in like he said. Also some fuel injection cleaner would be a good idea. Excessive carbon buildup can occasionally cause misfires issues.
If not then check each component. If you don't have the equipment then swap the parts with the a good cylinder and see if it follows. If it does the part is bad. If not then you need to take it to someone with the proper equipment.
Good luck!!! keep us posted
10-08-2012, 11:09 PM
#13
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Your kitties are constipated causing the misfire. Throw a new y-pipe on it and you will be good to go. Hell that even could be causing your perceived transmission slip you were talking about earlier because the motor is not making any power. I have also seen that.
10-09-2012, 08:54 AM
#14
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I hope that is the main issue with all my perceived troubles. New y-pipe will be in on Thursday or Friday so I will post back and give results once I have it installed.
10-12-2012, 09:41 AM
#15
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Ok. Got the new y-pipe put on last night, drove the truck around for a minute, stopped, hammered on the gas and layed a 75' black mark. Borrowing a scanner from a buddy today to clear codes and read what pops back up but the truck runs great, again. Inside of the exhaust pipe, past the cats, was wet with black soot and unburned fuel so I am assuming maybe the MAF code is possibly true which would have led to my cat issue, possibly. Thanks for the replies guys, I use to work on everything myself and was a little more in tune to problems but never would have guessed the catalytic converters.
10-14-2012, 10:18 PM
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Ended up the light came back on and I scanned it. O2. Was 4 O2 codes. Thought a minute. Layed down under the truck and yep, didnt plug that one back up. What I get for working in the dark while im pissed off. Anyways, plugged it up, cleared it, drove it and it runs great with no codes. Thanks again for all the help guys. Now I have to fix the gas gauge......
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