ok so i ran the ecu diagnosis and got 0511, 0512, and 0304.... i used the decoder in the stickies and 0304 is knock sensor but it wont tell me what 0511 and 0512 is.. can anyone tell me?

 

http://www.permoveo.ltd.uk/tabid/122...n/Default.aspx
p0512 bad grounds check them all ,, (worst case get a 8 or 4 awg wire attach it to the long bolt of the starter to the ground of the battery ..

p0511 iac valve ( idle air control valve issue) this is random check it first and there is a way to check it or do what I did .. remove the intake clean the crap out of the throttle body and maf sensor and try a Lil sea foam my issue cleared up after some driving .. and make sure your using 93 octane ..may not b related but it makes a huge difference in performance ..

I hope this helps every scenario is different

 

Thanks alot for your informative reply, i will run a 4 guage wire from the long bolt on the starter to the neg batt terminal.. But for the iacv should i just take it off and clean it out with carb cleaner for best results? and of course clean out the throttle body aswell.. I have also already cleaned the maf with CRC mass airflow sensor cleaner.

 

yes clean the throttle body, but use sea foam as described .. i hope the info helps lmk hiw it works out..

 

btw on that website i put in 0304 and it said its #4 cylinder missfire but the link on the stickies says its the knock sensor lol which one is correct?

 

is the 0304 from the self diagnostic or is a P0304?

0304 from the self diagnostic = Knock Sensor
P0304 code = Cylinder 4 misfire

 

All following codes are self diagnostic.. 0511, 0512, and 0304, The decoder wont tell me what 0511, and 0512 is but only tells me 0304 which is knock sensor.

 

P0140 (0512) REAR O2 SENSOR
P0137 (0511) REAR O2 SENSOR


Post 7,506 http://forums.maxima.org/4th-generat...ml#post8146357

 

so essentially both those codes refer to one oxygen sensor which is right after the cat in the mid pipe im guessing.. correct me if im wrong.

 

Do you happen to know if you're car is CALI Spec?

 

i would doubt that it is a cali spec because the production date is 07/97 and i live in canada and car was bought in canada. I also looked under and saw 2 o2 sensors in the y pipe and 1 right after the cat.. but the cat looked like it had a spot for a 02 sensor in it but there was a bolt there.. reason being is prolly that cat was made for cali and non cali spec and of course the cat is aftermarket bosal

 

is that right?? i didnt think it mattered unless u were s/c or turbo.

 

^open your owners manual and find the recommended octane..you'll be surprised

 

You do not have a California car, they have 4 O2 sensors. Canadian and US federal spec cars only have 3 sensors, just as you described. And the production date means nothing in this situation. Maximas from 1995 through 2000 and part of 2001 are like this.

Your car - non California


California cars and 2001 and later

 

ok thanks for posting the diagram it makes sense now.. the code is there because i have a little exhaust leak right before the rear O2 sensor at the flange where the cat meets the mid pipe. ill get that sorted out and a new knock sensor and my CEL should go off.. Fingers crossed!