hey i just got a 95 maxima, when i got it the engine light was on, everything seemed perfect, next day i checked out the engine light codes on the ecu(codes 0304, 0901, 0302). needs a Front Right Htd 02 sensor heater, knock sensor and maybe some egr cleaning. started it it up and the rpm went down past 300 then up to around 1500 and so forth then eventually started to level out at around 600 or so. anyone have any ideas why? mileage is 200 000 km btw

 

anyone?

 

I would start with the codes make those few repairs then go from there
I have seen EGR valves do that in some imports

 

i have the same dang problem. check into the egr system. thats the problem with mine. the dealer wanted like 450 bucks to clean it out for me. as you might of already noticed, the egr on this maxima is a pain in the rear. price and lazyness has left mine still uncleaned......my money is on your egr.

 

thing is when i first got it it started up fine, now it has an idle problem, only thing ive done to the car since getting it is getting the codes from the ecu and reset the engine light.

 

the dealer wants to use your lack of knowledge to his advantage - read up on the egr, i have a plugged up one + a code and the car runs without any probs.

OP - clear the codes and see if it happens again and if they come back. there's a $hit load of threads on idle problems which might help you troubleshoot yours ie iacv, tb, tps etc. do some searching.

 

spend a day taking your throttle body, idle air control valve, and egr tube out and hose them down with throttle body cleaner or carb cleaner and wipe down. You may have to adjust idle with throttle position sensor unattached afterwards. This is what fixed my idle fluctuating and got rid of the 0302 code. Also remeber it will still idle high when engine is cold and will eventually come back down to 600 rpm when warmed up.

 

Also check that vacuum hoses are connected properly, and not cracked. A vacuum leak can cause poor idle. However, you wrote that it became steady after a while.

When the engine is cold EGR isn't used, especially not at idle, so if you meant a cold start above I doubt the EGR problem is causing the idle to swing.

davidforehand posted good advice.

 

I have a similar problem. Any luck figuring out what is wrong?