I honestly have no idea how to search for these issues. I tried but I can't articulate this issue in a search. I am sorry for the new post but seems the best way to go. If there is a typical issue please feel free to post a link thanks.

Two things, might be related.

1. When I am on a hill facing up a few times when I put my foot off the brake my car starts rolling backwards like it's in neutral. Then when I put my foot on the gas there is a funny noise and it seems the gear or something happens and I get power to move forward up the hill. The noise to me is quite unnerving like it should NOT be happening.

2. A couple of times when I have backed up out of a parking spot, when I come to a stop I hear a noise like a spring and while I am turning the steering wheel and putting the car into drive.

I am prying these are not signs of a nightmare.

 

Ive heard a spring sound around the accelerator when I was in mud and the wheels starting slipping. Its the TC kicking it. Is that the spring noise youre talking about?

Hopefully someone else chimes in with some help. Hope its nothing major.

 

1 - your hill assist (brakes/trans are supposed to stay engaged keeping you from rolling backwards) isn't working properly. Not a big deal. When you give it gas, b/c the wheels are rolling the other direction, the traction control is kicking in b/c it 'thinks' you're getting wheel spin. Thus, it cuts power to the wheels hoping to engage traction as opposed to spin. Should see the t/c dash on light activate at this time too

2 - not sure exactly what you are describing here but it could be the same thing... t/c engaging if you're not completely stopped.

Good luck

 

I will look at the dash next time. It's such an awkward thing to happen I don't think to look. To me it's really scary. I worry about big issues I can't afford going wrong with the GX lol! Selling my RX this week I hope so I will not have a back up.

 

Try stepping on the gas a little, when your foot is on the brake, before you release the brake, so it doesn't roll backward on a hill once. If the sound is gone, then what the others said is correct.

 

Yeah when on a kind of steep hill is when it happens. Not often and it's more a clicking sound than it's like something locks in as it should.

 

What is happening is GX on a ascending a hill, the Hill Start Assist Control operation get automatically kicks in, should get the brake system gets activated for 3 second momentarily and the truck moves smoothly. But I still dont get the part how you lose power at this point.

 

What you're seeing is perfectly normal. The system is momentarly applying brakes to stop you from rolling backwards. Unfortunately, the system doesn't work too well. Read through this thread, it has good information to know about Hill-Assist feature and its limitations:

http://us.lexusownersclub.com/forums...-system-work/#

 

That's definitely Hill Start Assist Control kicking in. -- While the noise is unnerving, it's absolutely normal and you should see the orange indicator light-up on the dash when it occurs.

My IS250 AWD does the same thing though not as loudly from the mechanics of it kicking in and when it's really trying hard, it lets me know audibly with the beeping noise.

I run into this all the time in downtown Seattle with the really steep hills. -- I suck at driving a manual too...

Cheers,
Kermee

 

Thanks guys. Makes me feel allot better. I will read that thread. So far it has not happened again on that same hill in the same spot.