Misfire
Thread Starter
|
Senior User
Joined: Dec 2005
Posts: 159
Likes: 0
Misfire
Howdy all. Though I'm new to the forum I've been reading the posts for a few months now and found this site to have some of the best info on it. So, I thought I'd throw a question out there about a problem I can't seem to figure out.
I have a 97 F150, 4.2L V6, 2wd with a 5spd manual. I got the truck with a blown motor. It still ran but had a rap and the sump had lots of water in it. Couldn't find a new motor so I put in a rebuilt. When I finally got it going it had a CEL for an O2 sensor which I replaced. CEL still off but I'm getting a occaisional shudder, usually under load (up hills) in 5th. I have an Autotap scanner/diagnostic tool on my laptop and leave it connected when on trips over 50miles (frequent). The AutoTap has extended Ford paramiters which include "cumulative misfire Cylinder #" and "Low word cumulative misfire cylinder#". I have it set up to monitor all 6 cyclinders for both parameters. Here's the problem, I show nothing in the "cumulative Misfire" but I am getting misfires in the "Low word..." parameters. Mostly in the number 2 cyclinder and occaisionally in the 1 and 5. I can really feel the ones in the #2 but not the others. Unfortunately, B+B Electronics (makes the Autotap) can't give me much help on what the parameters mean as they are propriatary to Ford.
When I put the motor in I replaced the old Denso plugs but I can't recall what I put in, Bosch or Denso double plat. I recently replaced the old Borg-Warner wires with OEM Motorcraft wires (found these to be the only ones that meet mfg'ers spec of 5K ohms/ft). This helped for a couple days but now it's right back to missing mostly on the #2. As I said it only misses occaisionally, about 200 times in 200 miles and usually on hills in 5th. In general the engine feels weak in 4th and 5th at 70-75mph on hills. I drive most often in central/northern New England and there are lots of hills.
Sorry this is a bit long but I figured the more detail the better. Anyone out there have any thoughts on this, it's driving me crazy.
I have a 97 F150, 4.2L V6, 2wd with a 5spd manual. I got the truck with a blown motor. It still ran but had a rap and the sump had lots of water in it. Couldn't find a new motor so I put in a rebuilt. When I finally got it going it had a CEL for an O2 sensor which I replaced. CEL still off but I'm getting a occaisional shudder, usually under load (up hills) in 5th. I have an Autotap scanner/diagnostic tool on my laptop and leave it connected when on trips over 50miles (frequent). The AutoTap has extended Ford paramiters which include "cumulative misfire Cylinder #" and "Low word cumulative misfire cylinder#". I have it set up to monitor all 6 cyclinders for both parameters. Here's the problem, I show nothing in the "cumulative Misfire" but I am getting misfires in the "Low word..." parameters. Mostly in the number 2 cyclinder and occaisionally in the 1 and 5. I can really feel the ones in the #2 but not the others. Unfortunately, B+B Electronics (makes the Autotap) can't give me much help on what the parameters mean as they are propriatary to Ford.
When I put the motor in I replaced the old Denso plugs but I can't recall what I put in, Bosch or Denso double plat. I recently replaced the old Borg-Warner wires with OEM Motorcraft wires (found these to be the only ones that meet mfg'ers spec of 5K ohms/ft). This helped for a couple days but now it's right back to missing mostly on the #2. As I said it only misses occaisionally, about 200 times in 200 miles and usually on hills in 5th. In general the engine feels weak in 4th and 5th at 70-75mph on hills. I drive most often in central/northern New England and there are lots of hills.
Sorry this is a bit long but I figured the more detail the better. Anyone out there have any thoughts on this, it's driving me crazy.
Thread
Thread Starter
Forum
Replies
Last Post
jerryXTX
2004 - 2008 F150
13
Apr 19, 2012 09:08 PM
maceslin
Explorer, Sport Trac, Mountaineer & Aviator
9
Jul 28, 2006 07:47 PM
frozentexan
Modular V8 (4.6L, 5.4L)
4
Nov 28, 2005 08:09 AM
