I recently helped my friend install a new alternator and battery on his 99 Maxima and at same time changed his coil to 97 coils. Now when he drives and puts the car into N while costing the car idles at 1500 until he comes to a stop. Then when sitting at a stop it will range from 600-900 rpm. Sometimes at 800-900 while other times at 625-750. What can be the problem?

 

'99 maximas are very tricky with their ecu's. in my experience with them, they required everything electrically to be replaced with another '99 part....tried to switch a '99 maf with a '98 maf once and the car would idle just like how you described...had to replace with a 99 and it ran fine.

 

Coasting in Neutral is not a good thing to do, first of all.

Secondly, it sounds like either a bad or clogged IACV or EGR valve.

 

says who?



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