Yep. The tps wears over time. It clears out at the higher throttle level because less wear occurs there. It usually is more common in a stick shift.
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Yep. The tps wears over time. It clears out at the higher throttle level because less wear occurs there. It usually is more common in a stick shift.
Interesting......I'm having same problem with my swap. My misfire is on #5 and I have done all the same procedures to try and diagnose. I've never thought about the tps. My swap is a 4.8, 4l60e into a 72 c10.Quote:
Originally Posted by Skylark
I replaced the Throttle Position Sensor. No change.
Can we get a video of the misfire
I had the same problem when I did my swap which was 2 years ago. Car would idle a little rough and part throttle was rough but wot truck ran great. I took a temp gun and found #8 header primary was a lot cooler at idle than the other cylinders. Changed that coil on #8 and truck has run great ever since.
Repair shop wants to replace the fuel pump. 52psi at idle and low load. I hope that fixes it.
That's not terribly low. I hope that fixes it as well.
Mine is lower than that at idle and runs good. Key on engine off, my pump is within spec at 55psi. I had a random misfire a few days ago only when it was warmed up. I opened the hood and heard the plugs arcing. I changed the plugs and wires and did not use the OEM plug boot guards. No more misfire. I know I will need to change the fuel pump soon enough but right now it is still going strong.
I have chased problems like this on a few vehicles through the years so info is not LS specific. Have you checked and double checked all of the grounds and made sure they had a clean surface to contact. Good luck with this as it is a PITA!
Yeah, please keep us posted. I'm leaning more to the tune but it really could be anything.