When coasting to a stop the Rpms jump up a little bit (normally jumps when it reaches around 1000-1100). You can sometimes feel the car lurch forward a little bit also. Is this normal?
The transmission is down shifting and yes a very slight sudden slowing when it happens is normal. When coasting to a stop, if you use the shifter to go to a lower gear you will eventually hit a gear where this can be felt greatly. Put the car in drive get up to about 25 MPH start coasting and shift it to 2nd.
You should never notice the car downshifting on its own while applying the brake pedal in a normal manner.
Ok so the small lurch forward is normal?? And you mean when you brake the rpms shouldn't jump up like they do when your coasting?
Or do you mean you shouldn't be able to feel it when it downshifts while applying the brakes?
Number two the car still downshifts but because of the applied brakes you wouldn't feel it.
But its normal for the car to have a very slight increase in speed for a split sec when it downshifts? Just trying to make sure I understood what you said in the first message.
If you have ever driven a manual trans you know that to easily downshift, without pushing the clutch. You take the car out of gear and have to give the gas pedal a slight push to increase the rpms to match the vehicle speed for the lower gear. An automatic doesn't have a clutch so it is exactly the same but its all done by the computer and the slight push forward is just the computer not slowing the engine down just yet. When you are driving a rear wheel drive vehicle in snowy or very slick conditions it is a very good practice to put the vehicle in neutral because only the front brakes start grabbing in a minimum braking condition. When the vehicle downshifts the exact same thing happens and the downshift alone can cause the rear wheels to slightly accelerate or even lock up and cause a spin out. A very slight very momentary but sudden slowing or speeding up during a downshift while coasting is normal and you shouldn't worry about it.
Ok thank you for your help. One more question for you. When shifting into drive there is a small delay. The delay is around 1 second, maybe a little more but not quite 2 seconds. Should I be concerned about that?
It may help to have the trans fluid and filter changed. Make sure you don't have it flushed by a local oil change place. The oil change places flush machine should only be used if the filter has already been replaced. The machine is designed to remove the old fluid from the conerter and its honestly a waste.... As for your question, a second isn't bad 2 seconds would convince me to replace the fluid and filter. Any more than that and I would start worrying about the trans not having sufficient fluid flow and that will cause pressure to be low causing slippage during shifting.
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