I noticed that while I'm using cruise control above 70 mph that the engine rpms go up 50 rpm and holds for no more than a second and then down 50 rpm and holds no more than a second, this repeates seemingly endlessly, or at least while the engine is under load. It is so slight that I could barely notice it at first. I can't even see the tachometer move up and down and had to use the bluetooth OBDII device to confirm. If I sit up straight without my back touching the seat the acceleration / deceleration will cause my upper body to barely sway back and forth.
I can't help but think this may have something to do with torque converter locking and unlocking but would it be this gentle?
I changed the transmission fluid last October using this method: Transmission Fluid Exchange Writeup - https://forum.ih8mud.com/threads/transmission-fluid-exchange-writeup.19299/
I somehow managed to screw it up and didn't replenish a pint of fluid during one of the cycles, then drove about 15 miles with it slightly low and had some weird shifting, I posted about it here: RTH: Transmission Dipstick Reading - https://forum.ih8mud.com/threads/rth-transmission-dipstick-reading.1229439/#post-13490766
I've been checking the transmission fluid level often and it has been correct and looking as fresh as last October every time.
I'm not sure what else this could be, otherwise the engine sounds and feels good, maybe a slight lack of power but that could just be in my head, it has been much warmer lately so higher intake temps might account for that. I did just check the spark plugs and they looked great.
Anybody else have this problem?
Thanks in advance
I can't help but think this may have something to do with torque converter locking and unlocking but would it be this gentle?
I changed the transmission fluid last October using this method: Transmission Fluid Exchange Writeup - https://forum.ih8mud.com/threads/transmission-fluid-exchange-writeup.19299/
I somehow managed to screw it up and didn't replenish a pint of fluid during one of the cycles, then drove about 15 miles with it slightly low and had some weird shifting, I posted about it here: RTH: Transmission Dipstick Reading - https://forum.ih8mud.com/threads/rth-transmission-dipstick-reading.1229439/#post-13490766
I've been checking the transmission fluid level often and it has been correct and looking as fresh as last October every time.
I'm not sure what else this could be, otherwise the engine sounds and feels good, maybe a slight lack of power but that could just be in my head, it has been much warmer lately so higher intake temps might account for that. I did just check the spark plugs and they looked great.
Anybody else have this problem?
Thanks in advance