Hi, Good Greetings,
Thank you for all the information you provide.
I have Nissan Patrol, 2012 model but Road registration was done in Dec. 2013 and has done 75000 km,
its an Automatic Transmission with V8 Engine 400 Hp,
As my question states, keeping the car AC on if I drive in congested area or small streets with lot of Humps, turns etc., then the engine revs up in slow movement, if I turn OFF AC at this point the car runs with good pickup and no more revs or surging issues,
on a long road or high way there is no problem,
From the dealer replaced Fan Coupling assembly kit, cleaned throttle body, and regular maintenance. Recently did major service changing all oils, fluids and filters including Transmission oil etc.,
Did the computer scan and there is no error code related to the transmission, and all are pass,
I have noticed that when the car shifts gear from 1st to 2nd it makes that engine surging noise RPM raises but car doesn't move the way it supposed to be, right at that moment if I turn OFF AC this surging or Revs are not there at all
If there is a delay or transmission slip then it should also occur during the AC is OFF correct? Why only when AC is ON this happens, I took this to many garages but did not get any valid reason and i am afraid that I might spend more money rather getting the right fix for it.
Please suggest, I apologies for the long message.
thank you
Realize everything is computer controlled these days and turning the AC on gives the electrical system a larger strain when you turn it off so seems like you have an electronic problem there. Start with obvious have the alternator and battery low tested probably one of those is bad and that's not some kind of computer glitchy problem that Nissan's are known for
Thanks for the quick response,
A quick note: The Battery is new and still under warranty, Drive Belt was replaced along during the Major service done couple months ago, before it reached ( 75 K ) mileage,
Alternator : I will take this to have a check, does this drive belt and Alternator would cause engine to Rev up/surge? specially in very slow driving ( unless I drive fast or the gear shits to 3 or 4 this revs would continuously occurs.
2) when Nissan replaced Fan coupling assy. whenever I start the car in the morning or after few hours Fan makes loud noise and stays for about 10sec then goes to normal, when I asked about this they said its new and would take some time to get normal.
Is it something related to Transmission ? I saw your video to use Lucas transmission fix, does this help in my case?
Thank you once again.