Nissan Repair: 2001 nissan sentra gxe idle problems, mass airflow sensor, mass airflow sensors

Question
QUESTION: hello. I've been having idle problems for about 2 months now i haven't been driving the car for about a month..i changed the MAF IAT and coolant temp sensors...the car runs fine when its cold and when it warms up but when i turn it off it idles crazy from around 500 to 1200 rpm but if i press the gas it chokes itself out..until it get to around 2300rpms... any thoughts on what it might be????

ANSWER: Adam,

There are no codes present?  If you have an idle problem and you have replaced all the usual suspects.  I would be looking at the idle air control valve to make sure it is not sticking.  I have had so many where you just take the unit off and clean and reinstall it and it works fine.  Also, make sure that the mass airflow sensor is working properly.  Get a Haynes Manual or the like for the test values and a volt/ohm meter to verify that the new mass airflow sensor is working properly.  A Sentra of your year model seems to eat mass airflow sensors and they are not cheap.  Email me back if you need more.

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QUESTION: theres no codes now but there was 2  codes  o2 sensor lean bank 1 and bank 2.. but they went away after i replaced the MAF...

Answer
Adam,

Make sure the hose between the MAF and the throttle body is in good repair as in no cracks and the clamps are tight.  If this is good then check the idle air control valve connection.  Remove it and clean it and reinstall.  Email me back if that does not do the trick.  No codes makes this a difficult problem to diagnose.