I am getting the error code above. IAV relearn will not hold per the mechanic I took it to, and SES light keeps coming on. I read that a worn, but not faulty, power steering pressure switch could be a cause for a high idle. The reason I am investigating this as a possible solution for me is that when I bought the car, the P/S pressure hose was leaking to the point that the reservoir was constantly empty. I changed out the hose, and the leak is gone. I did not change out the P/S pressure switch. I have taken it into a mechanic, and after he tried the relearn multiple times with a consult computer, he gave up and told me to take it to Nissan. Have you heard of the pressure switch causing high idle before on a 04 Maxima? If the TB is clean and vacuum hoses are good, is this the likely culprit, before I go to the ECU? Or could there be something else?
My car has 175000 miles.
My car has a manual transmission.
Hi there. The code P0507 means that the idle air control valve (IAC) is registering a higher rpm than normal. Check all of the vacuum lines to the engine. A small vacuum leak will cause the engine rpm to be higher than normal.
If the vacuum lines are in good shape and there are no leaks, then check the IAC for a voltage read out. You will need a digital volt meter and a back probe pin. Put the back probe pin into the wiring harness put the volt meter on the pin. Register what the voltage is reading. If the voltage output is near the voltage input, then the IAC needs replaced.
If the voltage is low and when you throttle the engine the voltage goes up, then you will need to check the mass air flow sensor (MAF). Check to see if the MAF is dirty or oily. If the sensor is dirty, then I suggest replacing it with a new sensor.
Check the power steering pressure switch for power to it and if the switch is working.
If all of the sensors and switches are reading good and there is no problems with them, then I recommend having the computer flashed (reprogrammed) or replaced.
If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from YourMechanic, that can assist you with your engine light being on and the idle being higher than normal.
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