pulled a p0174 code off the ECU the other day and according to the FSM I should check the afm, fuel pressure, injectors,and o2 sensor. I have all the voltages within spec so, that jsut leaves a few items to check right?Symptoms include loud pinging and knocking even under minor acceleration/obviously high loads. While sittting at lights in drive the car will shudder alomost like broken motor mounts and idle will dip. If you put it into neutral the revs go back to normal like there suppost to. I am almost certain the pinging and this rough idle are related but this is the first time its ever thrown a code for it. I also tried pulling codes from it when this first started with the rough idle.
My friend has a 4 gas or 5 gas whatever its called at his shop and I have been tempted to see what he would charge me for the use of it. Since all the voltages are within spec do you think its gonna tell me anything different?peace.
1997 maxima GXE auto(bleh)191,554k miles
1997 Nissan Maxima SE auto #2 bank running lean
pull your coils and see if oil is leaking into the spark plug wells on the front valve cover. If there is no oil you have a bad coil, which one is near impossible to tell. With the pinging I suspect it is a coil. The reason your getting a lean code is due to the cyl not firing the fuel its getting. So the oxygen that enters the cyl goes out the exhuast due to it not being used during the combustion process. An O2 sensor measures just that. If you dont have a fire in the cyl the oxygen isnt spent. so no matter how much fuel there is ,the O2 doesnt see it.
Since there is really no way to tell which coil it is your best bet is to buy one and start by putting it in cyl 2 and see if it resolves your problem. While holding onto the one you took out. If it didnt fix it. swap cyl 4 with the one you took out of 2. agian if rough idle still persist swap again with 6. If your problem remains after that then there is more then one coil bad.
Note though. Typically when a coil fails you get either a P1320 or a P030x code. 1320 is ignition signal and P030x is cyl misfire [the x would be a numerical value from 0 to 6. 0 is multicyl misfire and 1-6 would indicate its respective cyl misfire.
Since there is really no way to tell which coil it is your best bet is to buy one and start by putting it in cyl 2 and see if it resolves your problem. While holding onto the one you took out. If it didnt fix it. swap cyl 4 with the one you took out of 2. agian if rough idle still persist swap again with 6. If your problem remains after that then there is more then one coil bad.
Note though. Typically when a coil fails you get either a P1320 or a P030x code. 1320 is ignition signal and P030x is cyl misfire [the x would be a numerical value from 0 to 6. 0 is multicyl misfire and 1-6 would indicate its respective cyl misfire.
-
nismopu
- Posts: 310
- Joined: Fri Jun 24, 2005 4:44 pm
- Car: 1987 Nissan 300ZX
1997 Nissan Maxima
1976 Datsun 280Z Turbo
took it around to a few mechanics and they seem to think its a metallic sound and not detonation. They printed off a few campaigns for me relating to the issue but I couldnt diagnose exactly the same symptoms from the campaigns that I was having with my car. Maybe I wasnt being to specific but the rough idle is only sometimes and not frequent enough for most mechanics to experience(usually how it works... right?)
This noise I have been hearing now seems mechanical and can be replicated with quick throttle jerks off idle or under load. It can be described as one quick hammer hit on a piece of steel and sometimes when under heavy acceleration the car wil shift and the noise can be heard again. I have eliminated the transmission as the cause because it can be replicated in neutral and you can hear the timing chain slacking as the RPM's drop. Could this be a bad tensioner due to the milaege on the car or is it my oil choice 10w30? Maybe the variable valve timing actuator is noisy? I have alot of questions I know but this car is really becoming a pain quickly. Thanks again for all your help. peace.
This noise I have been hearing now seems mechanical and can be replicated with quick throttle jerks off idle or under load. It can be described as one quick hammer hit on a piece of steel and sometimes when under heavy acceleration the car wil shift and the noise can be heard again. I have eliminated the transmission as the cause because it can be replicated in neutral and you can hear the timing chain slacking as the RPM's drop. Could this be a bad tensioner due to the milaege on the car or is it my oil choice 10w30? Maybe the variable valve timing actuator is noisy? I have alot of questions I know but this car is really becoming a pain quickly. Thanks again for all your help. peace.