4.7L Misfire codes on Cylinders 1, 2, 3, 5, 6, 8, but appears to run fine
#11
It would be worthwhile to replace it anyway. If it's showing low at idle, and you're seeing lean misfire codes, then the pump may be more than 1PSI low under operation. Besides, 170K is at the top end of a fuel pump's lifespan. Fuel pumps are wear items, and they do go out. You can extend their life by running top quality fuel at all times, and never letting it go below a quarter tank, but even then 200K is the most you'll likely see. If you decide to replace, avoid the cheap pumps, where electronic items are concerned you do get what you pay for. The only brands of fuel pump I recommend, or will ever use, are Carter, Delphi, Denso or factory. The first three are in the 100 to 150 range, the factory is over 300, for your truck.
Better to replace that pump now, while you can do it at your convenience, than to get stuck doing it as an emergency job with a potential 1000 dollar bill by the time it's said and done.
Better to replace that pump now, while you can do it at your convenience, than to get stuck doing it as an emergency job with a potential 1000 dollar bill by the time it's said and done.
#13
Vimes,
I very much appreciate your expertise on the fuel pump replacement. I wish I would have replaced it when I had the tank out to do the brake lines. That will likely be next on the list.
I received the new crank speed sensor in the mail on Monday. This morning on the way to work my CEL came on again. It looks like it takes me a week to complete a drive cycle. The same 7 familiar codes were present. Random misfire, and Misfire on cylinders 1,2,3,5,6, and 8. I just got home and swapped in the new sensor. I am going to take a 60 mile round trip to get some supplies, so I didn’t clear the code as then I’ll have to wait about a week to know the results.
If it was lean misfires, wouldn’t I have additional codes for that? ****, if they can diagnose a misfire with the O2 sensor, you would think I’d be seeing lean codes if that was the case. After all that is the primary purpose of an O2 sensor. From my limited knowledge, my fuel trim values seem normal. They haven’t been over 10 positive and go to like -12 negative when I shift gears. Driving at a steady 60mph, it averages 0 to -2.
I very much appreciate your expertise on the fuel pump replacement. I wish I would have replaced it when I had the tank out to do the brake lines. That will likely be next on the list.
I received the new crank speed sensor in the mail on Monday. This morning on the way to work my CEL came on again. It looks like it takes me a week to complete a drive cycle. The same 7 familiar codes were present. Random misfire, and Misfire on cylinders 1,2,3,5,6, and 8. I just got home and swapped in the new sensor. I am going to take a 60 mile round trip to get some supplies, so I didn’t clear the code as then I’ll have to wait about a week to know the results.
If it was lean misfires, wouldn’t I have additional codes for that? ****, if they can diagnose a misfire with the O2 sensor, you would think I’d be seeing lean codes if that was the case. After all that is the primary purpose of an O2 sensor. From my limited knowledge, my fuel trim values seem normal. They haven’t been over 10 positive and go to like -12 negative when I shift gears. Driving at a steady 60mph, it averages 0 to -2.
#15
Vimes,
I very much appreciate your expertise on the fuel pump replacement. I wish I would have replaced it when I had the tank out to do the brake lines. That will likely be next on the list.
I received the new crank speed sensor in the mail on Monday. This morning on the way to work my CEL came on again. It looks like it takes me a week to complete a drive cycle. The same 7 familiar codes were present. Random misfire, and Misfire on cylinders 1,2,3,5,6, and 8. I just got home and swapped in the new sensor. I am going to take a 60 mile round trip to get some supplies, so I didn’t clear the code as then I’ll have to wait about a week to know the results.
If it was lean misfires, wouldn’t I have additional codes for that? ****, if they can diagnose a misfire with the O2 sensor, you would think I’d be seeing lean codes if that was the case. After all that is the primary purpose of an O2 sensor. From my limited knowledge, my fuel trim values seem normal. They haven’t been over 10 positive and go to like -12 negative when I shift gears. Driving at a steady 60mph, it averages 0 to -2.
I very much appreciate your expertise on the fuel pump replacement. I wish I would have replaced it when I had the tank out to do the brake lines. That will likely be next on the list.
I received the new crank speed sensor in the mail on Monday. This morning on the way to work my CEL came on again. It looks like it takes me a week to complete a drive cycle. The same 7 familiar codes were present. Random misfire, and Misfire on cylinders 1,2,3,5,6, and 8. I just got home and swapped in the new sensor. I am going to take a 60 mile round trip to get some supplies, so I didn’t clear the code as then I’ll have to wait about a week to know the results.
If it was lean misfires, wouldn’t I have additional codes for that? ****, if they can diagnose a misfire with the O2 sensor, you would think I’d be seeing lean codes if that was the case. After all that is the primary purpose of an O2 sensor. From my limited knowledge, my fuel trim values seem normal. They haven’t been over 10 positive and go to like -12 negative when I shift gears. Driving at a steady 60mph, it averages 0 to -2.
I think lean codes start at 5% fuel cut on the LTFT
#16
Vimes,
I very much appreciate your expertise on the fuel pump replacement. I wish I would have replaced it when I had the tank out to do the brake lines. That will likely be next on the list.
I received the new crank speed sensor in the mail on Monday. This morning on the way to work my CEL came on again. It looks like it takes me a week to complete a drive cycle. The same 7 familiar codes were present. Random misfire, and Misfire on cylinders 1,2,3,5,6, and 8. I just got home and swapped in the new sensor. I am going to take a 60 mile round trip to get some supplies, so I didn’t clear the code as then I’ll have to wait about a week to know the results.
If it was lean misfires, wouldn’t I have additional codes for that? ****, if they can diagnose a misfire with the O2 sensor, you would think I’d be seeing lean codes if that was the case. After all that is the primary purpose of an O2 sensor. From my limited knowledge, my fuel trim values seem normal. They haven’t been over 10 positive and go to like -12 negative when I shift gears. Driving at a steady 60mph, it averages 0 to -2.
I very much appreciate your expertise on the fuel pump replacement. I wish I would have replaced it when I had the tank out to do the brake lines. That will likely be next on the list.
I received the new crank speed sensor in the mail on Monday. This morning on the way to work my CEL came on again. It looks like it takes me a week to complete a drive cycle. The same 7 familiar codes were present. Random misfire, and Misfire on cylinders 1,2,3,5,6, and 8. I just got home and swapped in the new sensor. I am going to take a 60 mile round trip to get some supplies, so I didn’t clear the code as then I’ll have to wait about a week to know the results.
If it was lean misfires, wouldn’t I have additional codes for that? ****, if they can diagnose a misfire with the O2 sensor, you would think I’d be seeing lean codes if that was the case. After all that is the primary purpose of an O2 sensor. From my limited knowledge, my fuel trim values seem normal. They haven’t been over 10 positive and go to like -12 negative when I shift gears. Driving at a steady 60mph, it averages 0 to -2.
#17
So, The CEL light cleared itself after driving 30 miles. After my second startup after leaving home, the light turned off.
I’m kind of ashamed to admit it, but I didn’t quite take everyone’s advise and I bought a NTK crank sensor this time. That one the truck seems to like fine. It didn’t like the Holstein brand one. I’m still curious how That sensor caused misfire codes, but no actual noticeable drivability problems. I know, I know, I basically spent as much on the two aftermarket sensors as I would have spent on a Mopar sensor in the first place. I just have a real hard time spending 3x as much on something that is just rebranded by Chrysler anyway. Maybe one of these days I’ll learn.
Thank you everyone for your informative replies.
I’m kind of ashamed to admit it, but I didn’t quite take everyone’s advise and I bought a NTK crank sensor this time. That one the truck seems to like fine. It didn’t like the Holstein brand one. I’m still curious how That sensor caused misfire codes, but no actual noticeable drivability problems. I know, I know, I basically spent as much on the two aftermarket sensors as I would have spent on a Mopar sensor in the first place. I just have a real hard time spending 3x as much on something that is just rebranded by Chrysler anyway. Maybe one of these days I’ll learn.
Thank you everyone for your informative replies.
#19
So, The CEL light cleared itself after driving 30 miles. After my second startup after leaving home, the light turned off.
I’m kind of ashamed to admit it, but I didn’t quite take everyone’s advise and I bought a NTK crank sensor this time. That one the truck seems to like fine. It didn’t like the Holstein brand one. I’m still curious how That sensor caused misfire codes, but no actual noticeable drivability problems. I know, I know, I basically spent as much on the two aftermarket sensors as I would have spent on a Mopar sensor in the first place. I just have a real hard time spending 3x as much on something that is just rebranded by Chrysler anyway. Maybe one of these days I’ll learn.
Thank you everyone for your informative replies.
I’m kind of ashamed to admit it, but I didn’t quite take everyone’s advise and I bought a NTK crank sensor this time. That one the truck seems to like fine. It didn’t like the Holstein brand one. I’m still curious how That sensor caused misfire codes, but no actual noticeable drivability problems. I know, I know, I basically spent as much on the two aftermarket sensors as I would have spent on a Mopar sensor in the first place. I just have a real hard time spending 3x as much on something that is just rebranded by Chrysler anyway. Maybe one of these days I’ll learn.
Thank you everyone for your informative replies.
#20