Hello All,
First I want to say thanks for all the great information on this site as it has proved tremendously valuable in figuring out the issue I have had with my 2003 Murano SL 2WD.
I had been dealing with a p0304 code for a while and did all the normal stuff like changed the coil pack and the spark plug with all helped mask the issue at hand. Last Nov(2014)I had changed all the spark plugs and filter after the code came back again. Though this time the car smelled like it was running really rich and was idling like crap and throwing smoke in the morning.
After the spark plug change and filter change there was still smoke in the morning and idling a bit rough but not enough for me to think too much of it. I ran some cleaners through the tank and it seemed to start to go away. The code went away and the car was driving fine. Over the last month the code came back and and it seemed like a bit more smoke was coming out.
After trying hard to figure this one out, ruling things out like the spark plugs, coil packs, injectors, etc. Hooked it up to a scanner (elm327 and Android Cargauge pro) look at all the sensor readings etc to try to help me find my issue... nothing. Finally I went to a local mechanic and the diagnosis was a stick valve or a burned valve. Either way expensive. Well I got home and just kept reading and reading. Tons of posts, manual and more.
I started to retrace my steps since I have been working on the Murano and got back to the Intake manifold to make sure it was torqued to spec. When I got to nut number for I noticed that one of the hoses basically was coming off by itself. So I pulled the hose of to inspect it and the back side was torn. As a quick fix I cut off the bad part and popped it back on, turn on the car and it started smoking, but then started to go away. As did the rich smell of gas. The car started idling better so I took it for a good drive and no code.
Over the past few days I have been driving it I get no code and the car has been running great again.
This hose goes to the Power Valve on the side of the Intake Manifold. I don't know why specifically it was only giving me a misfire on number 4 but it was. I just wanted share this long story with everyone because I have read so many posts that people are mind boggled by these misfire codes. I don't know if this will help anyone else figure out misfire issue(s) but in the end this was my problem.
Attached is a picture of the Power Valve and the hose that gets connected to it.
P.S. I did check most of the lines and other stuff for leaks. I think if I had a leak down tester I would have gotten this one much quicker.
Good Luck.
First I want to say thanks for all the great information on this site as it has proved tremendously valuable in figuring out the issue I have had with my 2003 Murano SL 2WD.
I had been dealing with a p0304 code for a while and did all the normal stuff like changed the coil pack and the spark plug with all helped mask the issue at hand. Last Nov(2014)I had changed all the spark plugs and filter after the code came back again. Though this time the car smelled like it was running really rich and was idling like crap and throwing smoke in the morning.
After the spark plug change and filter change there was still smoke in the morning and idling a bit rough but not enough for me to think too much of it. I ran some cleaners through the tank and it seemed to start to go away. The code went away and the car was driving fine. Over the last month the code came back and and it seemed like a bit more smoke was coming out.
After trying hard to figure this one out, ruling things out like the spark plugs, coil packs, injectors, etc. Hooked it up to a scanner (elm327 and Android Cargauge pro) look at all the sensor readings etc to try to help me find my issue... nothing. Finally I went to a local mechanic and the diagnosis was a stick valve or a burned valve. Either way expensive. Well I got home and just kept reading and reading. Tons of posts, manual and more.
I started to retrace my steps since I have been working on the Murano and got back to the Intake manifold to make sure it was torqued to spec. When I got to nut number for I noticed that one of the hoses basically was coming off by itself. So I pulled the hose of to inspect it and the back side was torn. As a quick fix I cut off the bad part and popped it back on, turn on the car and it started smoking, but then started to go away. As did the rich smell of gas. The car started idling better so I took it for a good drive and no code.
Over the past few days I have been driving it I get no code and the car has been running great again.
This hose goes to the Power Valve on the side of the Intake Manifold. I don't know why specifically it was only giving me a misfire on number 4 but it was. I just wanted share this long story with everyone because I have read so many posts that people are mind boggled by these misfire codes. I don't know if this will help anyone else figure out misfire issue(s) but in the end this was my problem.
Attached is a picture of the Power Valve and the hose that gets connected to it.
P.S. I did check most of the lines and other stuff for leaks. I think if I had a leak down tester I would have gotten this one much quicker.
Good Luck.
