I have 2009 G37X 7AT with 72K miles.
First, i had check engine light due to camshaft position sensor fail on passenger side.
I bought new OEM sensor and replaced it.
After i replaced sensor, it won't go over 3500 RPM and only go through 1st to 3rd gear.
It feels like fuel cut off at 3500 rpm and also shift very hard from begining.
It will shift from 1st to 7th if i do manual mode.

Is there anyway to reset the ECU or Tranny?
Anything else i should change?
BWT, there is no CEL.

Please help me solve this issue!!!!

 

there's an ecu reset in the diy section of the forum. search.

 

+1

Look on the forums for how to reset the ECU, your car's probably in "limp mode"

 

in the service manual, limit of 3500 RPM is listed as fail safe mode if there is something wrong with the VVEL subsystem? it doesn't mention anything about not shifting beyond 3rd gear though.

 

"fail safe mode", "limp mode", potato, po-tat-o. Same thing.

Gotta reset the ECU or take it to your dealer. Might be something wrong with it that you're not aware of...

 

different DTC failures have different fail safe modes per the service manual. If the MIL (SES) light fails, then RPM is limited to 2500. MAF or oil pressure failures limit to 2400.

so, no, they are not all the same.

 

just start by taking the neg terminal off and on. recheck the connection to your CPS and anything you might have touched nearby

 

Thank you very much for all of your input!!!

I did find reset ecu from search but for g35's. Is this same procedure?

I also did neg terminal off but no help.

Double checked connections as well.

Does limp mode make tranny hard shift?
It was definitely unusual.

Thanks again for help!!!

 

its definitely a limp mode. I think that the next best step would be to reinstall the original CPS you took out before you had the limp problem.

you should test the original CPS by measuring resistance and running it across metal. you can find out which terminals to tap in the FSM. dont just replace a sensor because the CEL said so

 

yep, same procedure.

 

I have starting issue now with sensor hooked up.
It sounded like mis firing but barely start up with sensor unhooked.
Bought new battery but still no start with sensor hooked up.
Very strange......

Any idea please?

 

you bought a new battery because your car wouldnt turn on? you have to test devices before you replace them. you will waste a lot of money and time if you just throw random parts at a car

I have seen other cars disable the circuit to the starter switch if there was a CPS failure. replacing the sensor/cleaning it fixed the issue. clearing the DTC or bump starting or manually spinning the starter yourself got the car moving in the meantime.