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Transmission kicks while my car is idoling after a it warmed up

I drive a 2007 Buick Lucerne cxs 4.6 liter V8. It’s got about 171,000 miles runs great and I’m very happy with it. The transmission it self shifts fine and the fluid level is great. But after the car warms up if I’m sitting in idol while in drive with my foot on break preventing the car from moving the car it feels like the transmission will kick or Lurch. Anyone got an ideas as to what the issue is ?

The transmission is neutralizing and then reengaging.

One of the early signs of a transmission starting to fail.

Tester

Is there anyway to fix this or is it a lost cause ?

Perhaps it’s worshiping false idols as it is sitting in idle.
:wink:

What did you break? I hope that it wasn’t the brake pedal.
:wink:

All joking aside, you need to take your car to an independent trans shop (not a chain-run shop such as Lee Myles, Cottman, Mr. Transmission, or AAMCO) for diagnosis. If the trans fluid and filter have not been changed every 3 yrs/30k miles, you are actually overdue for transmission failure. However, only a qualified transmission specialist could give you a precise diagnosis.

3 Likes

The transmission has been serviced regularly and got a flush about 15,000 ago. But I will look around for good transmission shops near me.

+1
Ask friends, neighbors, co-workers, and relatives for the names of independent trans shops with which they have done business.

The transmission is on it’s way out.

I remember when this happened with my Chevy.

I’d be sitting at a stop, the transmission would kick, and I wondered who just hit me in the ass end?

Look in the rear view mirror, and there wouldn’t be anybody there.

Tester

When it happens in my car it’s very subtle. I can feel it but it’s Nothing that that violently moves the whole car. Almost feels like I ran over a bump in the road.

My only experience with this sort of behavior was on a Hyundai… however the same principle may exist in your vehicle as most modern cars use some variant of this system.

Your shifter has a cable…that cable goes to the trans shift arm to select which gear you will put the trans into… Many vehicles have an electronic device that monitors this movement of the shift arm and more specifically the shift shaft that goes into the trans… This is where the LED display of gear selection can come from for the dash… When this unit (shift control module?) starts flaking out… it can produce symptoms similar to what you are feeling.

Then again…it can also be something like your torque convertor dying inside…very possible also…

Try this to see what happens… engine running…In Drive, at a stop, same as before… but now hold the brake as you try to apply some gas… “power brake” basically…but not excessively… see what it does… Your answer will be telling

What am I supposed to be able to tell from this test you are suggesting ? What should I look for ?

I want to see if the condition you describe actually get worse if you apply the brake as well as the gas… see if you can recreate the condition… or make it occur at will. If so… that would be the torque convertor

Hey, I tried this test. Car didn’t lurch or kick but wouldn’t go past 1,800 rpms while the break was decompressed

Well thats good… because it really shouldn’t be able to. OK…we back where we started. I’m still leaning toward what I mentioned in my first post. I just wanted to see if the torque convertor was behaving normally…which that test tells us that it is working fine.

Nearly impossible to fix your issue from here… you will need the help of a transmission shop if you want to solve it…if the problem is that serious.