Can't get rid of the Misfire...
#31
Changed the fuel filter, had the tranny serviced. Double dosed the fuel with STP $7 injector cleaner (made with jet fuel, ya know...) Still occasionally misses. I am at my wits end. Maybe a second coil is going bad. Definitely imporved, but not gone. Went four days without a miss, even with me setting it up to fail. Any more suggestions???
Thanks...and keep the ideas coming!
Thanks...and keep the ideas coming!
#33
I can only described what worked for me. When I was pulling coils, I blew out each spark plug hole with an air compressor tube. I wanted to be sure nothing including moisture was in those holes. After I was sure they were clean, I replaced the coil with a different cleaned with compressed air coil. I'm going back to read your original description and see if it was similar to my missing problem.
#34
Your description, miles and vehicle are almost identical to mine. My missing has never returned. If you had two missing coils, I can see how that would compound the problem.
If you want to send me one or two coils at a time, I'll put them in my truck and test them. That's about all I can offer. If it doesn't miss for me it shouldn't be a coil.
If you want to send me one or two coils at a time, I'll put them in my truck and test them. That's about all I can offer. If it doesn't miss for me it shouldn't be a coil.
#35
After doing a little searching on this site, I have seen some people disconnecting the EGR valve and the problem went away. That probably makes it run a little richer. I wouldn't suggest replacing the EGR valve, since that didn’t' seem to fix their problem. In their case the controller was opening the EGR valve too far. This can get a little expensive shot gunning the problem. However I like the challenge (sometimes)…and it still could be another coil.
#36
#38
I also have almost exactly the problem you guys are describing. I have a '98 Expedition, 5.4 4WD for reference. It has about 110,000 miles. Recently I had the usualy #4 coil fail completely. I replaced it as well as the spark plugs. It ran fine for about a month, then it starts this miss on what is a typical uphill load. Part throttle acceleration and I get the miss about 50% of the time. Maybe it is me, but it seems to happen more often when the fuel level in the tank is lower, and the weather is hotter.
I intend to replace fuel filter because it should be reaplaced. If that makes no differance I will next pull the plugs out and look for problems. I suppose my next bet is going to be to replace the coils one at a time playing musical coils. I will followup with anything I find.
I intend to replace fuel filter because it should be reaplaced. If that makes no differance I will next pull the plugs out and look for problems. I suppose my next bet is going to be to replace the coils one at a time playing musical coils. I will followup with anything I find.
#39
Is it possible that there is water in the fuel.
Might try some drygas.
This will make any engine miss on a random basis.
The older engines had a two line fuel system and circulated the fuel.
These one line systems could get a load of water that wont go away until the injectors pass the fuel through.
Might try some drygas.
This will make any engine miss on a random basis.
The older engines had a two line fuel system and circulated the fuel.
These one line systems could get a load of water that wont go away until the injectors pass the fuel through.
#40
#41
#42
Sure seems that way. That was the last thing I tried. I think that I may have had a couple of issues. The coil absolutley made a difference. After I installed the coil in #4, the miss went away for 4 days. Right now, though, all is running OK. I'll report back next Saturday night.
Good luck.
Good luck.
#43
#44
#45
OK, I'm back...Mixed results. On the 350 mile ride out, it only misfired once. After light use for a couple of days (< 5 miles a day), I took it out on teh beach and pulled a couple of SUVs out of the sand. The 10 mile trip back to teh house, it missed a bunch!!!. Missed some on a 35 mile ride to the mainland. Leaving this morning, it missed in heavy traffic, but started running great after I got on the open highway. This is frustrating...
I'm going to try some more cleaner, and I think that I'll dielectric the boots again.......
I'm going to try some more cleaner, and I think that I'll dielectric the boots again.......