I got a P0300 i put spark plugs i haven't done the timing yet my next thing will be to replace coils but thank god I work for a dealer but not Nissan different brand but I still get good prices for my parts I can get Nissan coils for $72.00 each so I just don't want to buy the coils and guess at this so please help me out here any help I can get I will be grateful thanks a lot sorry It's a 5th Gen with a 3.5 motor thanks

 

First off, Periods...they are your friends.

Any other codes? Rough idle? What else have you done, and what symptoms are you experiencing? When I put mine back together I accidentally had the wires switched between coils 1&3. Once I fixed that she runs great.

 

First off get the FSM > http://www.nicoclub.com/FSM/maxima/ < and you want EC-317.

 

i had P0300 i changed my plugs boots and CPS sensor all at the same time, went away.

 

The 2002 Maxima does not have spark plug wires. I'm pretty sure the 3.5 VQ only has ignition coils over plugs.

 

He's referring to the coil boots. They can be changed separately if the contact starts to weaken. Changing the boot does not help the typical power transistor issue the VQ coils seem to have, but if it's just a weak contact between coil and spark plug then you can just change the coil boot.

They are not known to go bad very often though, so it may not make a difference if they are changed, but you won't know unless you try it.

RR5 has you on the right track with the FSM reference though. Pour through that and follow the procedures to the T and you should have some luck sorting it out.

-Nathan

 

Is it possible that you accidentally pulled one of the connectors an injector/injectors loose? Or loose enough to cause problems? Could you have a vac leak? Perhaps around the upper intake manifold? Check your grounds as well.
Also a little more info and maybe someone can point you in the right direction? Is the car running rough, poor idle etc? If so is it constant or random?

 

 

To be honest, before posting here the first thing that should be done is disconnect/reconnect all electrical connectors if only to rule out those as a problem.

 

^that doesnt seem very smart... unless something been replaced or recentley repaired then maybe id disconnect the battery and unplug and plug in sensors in that general area, or see if a plug or vac line was forgotten to be put back.

just my 2 cents..

 

Thats how we do it for computer and server troubleshooting my friend. Unplug stuff and plug it back in. Not too often, and we can't explain it but the stuff will start working after that.

-edit Oh and you are supposed to inspect electrical harness connectors for damage by unplugging them, says so in the FSM for nearly every diagnostic flow chart.

 

^He's spot on mate. Sometimes just unplugging things and plugging them back in works. It has worked for me before.

-Nathan