I replaced the head gaskets, timing chains, guides and tensioners, temperature sending unit, and thermostat. While it was apart I cleaned the throttle body and replaced the seals on the injectors. I made an error with the VVTi actuators by opening them up and the first time I tried to start it, I didn't have current to the coils. Took it back apart and replaced the actuators with OEM used ones. It started and idled to fast while throwing codes PO1168 and P0430. I followed the learning procedures for the accelerator pedal position, the learning procedure for the throttle valve closed position and the idle air volume learning procedure. The idle settled down to about 750 rpm and the truck seemed to run fine. I took it for a ride and admit to hammering on the throttle a bit to see what it was made of. Suddenly it lost power, would run but not good, nearly a limp mode and I barely made it home. It had a valve rattle in that mode. I checked the codes and found a PO300. I unhooked the battery overnight and started the next day and let it idle a while. It seemed fine and then the Service Engine System light began to flash and a rough idle ensued. I cleared the code, restarted and took a short ride. For the first 100 yards it seemed fine, then went into the limp mode and rattle again. I pulled over and found the PO300 code back on. I know that means multiple misfires. At some point I remember seeing the word actuator either on the screen of the code reader or the dash, and then it went away. I can't find a code with the word actuator and I really don't remember where I saw that word. I have not seen it since. After it sits and I clear the codes, it will start and idle ok for a while, then the Service System flashing light will come on and I get a rough idle. I think it might be time to head for a dealer and a more sophisticated analyzer. So I have two questions. First, anyone have a any similar experience? Second, will the analyzer at the dealership be able to pinpoint what might be causing the PO300 code?
Gopedal
P0300 is for random misfire for which you must not ignore. Each misfire means raw gas is getting into the cats. Your best bet is to go to NIssan and have the diagnose it for the fixed fee ($135?). Hopefully it is something definitive like a cam sensor.
My take: If it ran good then you stepped on it hard and then got P0300, I’d suspect your cats are getting clogged and can’t handle the higher volume of exhaust- so back pressure is created to the point of causing misfires.
The rattle could be a loose honeycomb in the cat.
The rattle could be a loose honeycomb in the cat.
If your truck was able to give codes for exactly whats wrong with your truck we would'nt need mechanics, just 10 dollar an hour parts replacers. Unfortunately it can't, it gives codes that can point you in the right direction but can have 5-6 different causes for every code set. This is where the experience and skill come to play along with the 125$ hr labor rate.
Found a bad driver side cat. Pulled the secondaries off and the driver side secondary was full of the guts from the primary. I've been studying the walker converters and want to be sure I order the correct one. Can anybody tell me if the driver side Walker cat is the 16467 or the 16468? Thanks.
An upstream problem(s) can cause a downstream cat problem. IOW, a failed cat may be a symptom of the original issue.
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
