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I recently got a 2000 Nissan Maxima after it sat for about 3 years and when It gets into the higher rpm's it starts making a pinging sound and it gets a little louder and faster as the Rpm's get higher. I took it to my local shop to find out why and why the check engine light was on and they told me the #2 o2 sensor was lagging but they told me fixing that may not take care of the pinging sound.

Anyone else have this kind of problem? The car runs great...just dont like the pinging sound and the light on.  

somewhere hiding on the engine is this device..



with a decent OBD2 scan tool plugged in.

finding this.. with the engine running at 1500 RPM..   tapping that with a long screw driver...  the GM factory i went thru decades ago.. used what looked like a solid car radio antenna with a ball tip.. and tapped on the block near the detonation sensor to see if the Computer heard it..  and the computer retarded the timing...

you could also have a problem with clogged fuel injectors...

you could have a problem with the EGR system...

the EGR system diverts some burned exhaust gasses into the intake to reduce oxygen concentration in the incoming air charge..    this lowers the combustion temp to reduce the formation of oxides of nitrogen.. NOX..  since there is less oxygen content.. the engine also needs less fuel to reach the proper air fuel ratio...  



warning.. operating the engine with it pinging WILL CAUSE DAMAGE to the engine.. resulting in significantly reduced engine life.. sometimes from years or decades.. to weeks.. or days..

yep...  you are melting the sides of the pistons.. clogging the rings..

if an injector is clogged.. you could have one cylinder leaning out..

if you have ONE of the EGR passages clogged.. you could lean out one cylinder and not know why..



please examine the live data and record it..

at at idle cold...

at idle hot..

at 25 MPH hot

at 50 MPH hot..

post the data...

if you don't have a scan tool... do you have a harbor freight tools store near you..

they have the HF 98164 scan tool..   that will do this.. and also graph the sensor voltage.. its a lot less expensive than the next model up..  i use one daily..   i also have advanced scan tools.. that cost well over 1000 bucks..   so its 130 bucks.. or well over 1000 ..

if you are going to invest in a scan tool.. don't buy any of the lessor versions than this...



you HAVE TO BE ABLE TO READ LIVE DATA STREAM.. and graph the live data stream.. not just look at snap shot data..