blown87notch
Member
O.k. I have a 00 5.4 expy. It is 4wd (AWD or 4wd, doesn't have the 2wd like some I have seen).
When we first got it there was no miss at all. When it started getting really cold it came a couple times, then when I had the codes checked (pass O2 lean) it went away. Couple months later it came back, changed the plugs and that helped for a couple days.
It was good about 1/4 of my 500 miles trip I took on Monday. I had to go over to wyoming and tow a car back. Most of the parts of wyo I was in near 6500 feet, so I was already lacking power. It wasn't too bad till I picked up the car and headed home. I had to pull a couple hills and it started getting bad. I stopped and let it cool down a bit before I pulled the big hill. It starts around 6300 feet then goes up to over 9000 feet. Neeless to say I barely made it over. The truck has poping and banging and jerking. I swear it must have been on 4-5 cylinders. The cel did come on then went off as I went back down.
Ever since I have been back I have been messing with it and reading here. I checked the code when I got home it was the same so I started looking at the vehicle. The pass side exhaust mani had two broken studs on the back and a big exhaust leak. Fixed those and one on the drivers side and it is all leak free now. I also remembered I had a bit of oil in one hole when I did the plugs, so I figured it might have been arching and making it miss. This was also on the pass side. I could only imagine what the ecm was thinking when it was reading o2 from the leak and fuel from the miss.
Tonight I took out all the coils, cleaned them (there was no oil in the hole from last time when I did the plugs) and I put the eletric grease on them and on the connections.
I also did a sea foam, cleaned the mass air sensor, chenged the fuel filter and got an oil change too while I was under it.
It has a ton more power now but there is still a small miss somewere. When it does start it will do it when it is driving then you can feel it when you stop, put it in park and idle. It mostly will start at light load low rpms. If I give it 1/2 or more throttle it won't do it, or at wot, just light throttle. It won't do it all the time, only after it is warmed up. With it doing it at idle I do not think it is a drivetrain problem. It is rpm related I think, any were under 2500 it will do it, never over.
I have hooked it up to a scanner everytime, even had the KOER tests and the only code I have gotten is the O2.
I have also checked for intake leaks, listened to the injectors with a scope, I cleaned them when I did plugs anyways.
Tomorrow I am going to look at the egr, I didn't think about that but now that I read the post I remember my 92 stang with mass air had problems if the egr wasn't working just right.
Other than the egr I am stumped.....it does run a ton better but summer is here and it is time to pull the stang to the track and the boat to the lake.
I forgot to add the rig has 189k on it, and I have pulled that hill with around the same load twice before with no problems, pulled it like a dream.
When we first got it there was no miss at all. When it started getting really cold it came a couple times, then when I had the codes checked (pass O2 lean) it went away. Couple months later it came back, changed the plugs and that helped for a couple days.
It was good about 1/4 of my 500 miles trip I took on Monday. I had to go over to wyoming and tow a car back. Most of the parts of wyo I was in near 6500 feet, so I was already lacking power. It wasn't too bad till I picked up the car and headed home. I had to pull a couple hills and it started getting bad. I stopped and let it cool down a bit before I pulled the big hill. It starts around 6300 feet then goes up to over 9000 feet. Neeless to say I barely made it over. The truck has poping and banging and jerking. I swear it must have been on 4-5 cylinders. The cel did come on then went off as I went back down.
Ever since I have been back I have been messing with it and reading here. I checked the code when I got home it was the same so I started looking at the vehicle. The pass side exhaust mani had two broken studs on the back and a big exhaust leak. Fixed those and one on the drivers side and it is all leak free now. I also remembered I had a bit of oil in one hole when I did the plugs, so I figured it might have been arching and making it miss. This was also on the pass side. I could only imagine what the ecm was thinking when it was reading o2 from the leak and fuel from the miss.
Tonight I took out all the coils, cleaned them (there was no oil in the hole from last time when I did the plugs) and I put the eletric grease on them and on the connections.
I also did a sea foam, cleaned the mass air sensor, chenged the fuel filter and got an oil change too while I was under it.
It has a ton more power now but there is still a small miss somewere. When it does start it will do it when it is driving then you can feel it when you stop, put it in park and idle. It mostly will start at light load low rpms. If I give it 1/2 or more throttle it won't do it, or at wot, just light throttle. It won't do it all the time, only after it is warmed up. With it doing it at idle I do not think it is a drivetrain problem. It is rpm related I think, any were under 2500 it will do it, never over.
I have hooked it up to a scanner everytime, even had the KOER tests and the only code I have gotten is the O2.
I have also checked for intake leaks, listened to the injectors with a scope, I cleaned them when I did plugs anyways.
Tomorrow I am going to look at the egr, I didn't think about that but now that I read the post I remember my 92 stang with mass air had problems if the egr wasn't working just right.
Other than the egr I am stumped.....it does run a ton better but summer is here and it is time to pull the stang to the track and the boat to the lake.
I forgot to add the rig has 189k on it, and I have pulled that hill with around the same load twice before with no problems, pulled it like a dream.
