no engine braking?

A

Al's Chop Shop

Member

:

08 CX-9 Sport

• Feb 2, 2010

• #1

i hate that i can't use engine braking in the CX9. when i manually downshift i can feel the compression braking start, but then its like magically gone. i am assuming the car is 'fly by wire' (like the runaway toyotas) and its trying to 'outsmart' me by applying a bit of throttle. i've compression braked every vehicle i've ever owned when decending steep grades. i live around a lot of hills, and i hate that the engine will not hold me back. i am afraid how short the brake life will be (as well as risking the rotors warping) because i must use the brakes so much when coasting down hills.

anyone else noticed this?

Al

 

J

JC-MP5

Member

:

1994 BG6S

• Feb 2, 2010

• #2

Could it be that automatic cars almost always go into "neutral" when you aren't on the gas?

 

F

fxpthl

Member

• Feb 3, 2010

• #3

Compression Breaking Works Great For Me

After one year and 23K miles, we have traveled many a mile in which I used the transmission to help us going down steep grades. I have never had a problem with the car in this manner and would rather do this than constantly use the breaks. It does sound like the posting is referring to down shift way too low of gear. Depending on the grades, use of the down shift method really works great.

 

P

petesamprs

• Feb 3, 2010

• #4

CX9 SportOwner said:

I use compression to control descent all the time. with cruise engaged, the car will slow itself to maintain speed. In Manual I always use it to slow down on hills. Are you jamming it into such a low gear that the RPM limiter kicks in?

Click to expand...

+1. Manually downshifting to slow a descent works fine for me as well. Of course given the weight of the CX-9, you may still creep up to the car in front of you and need to use the brakes.

 

A

Al's Chop Shop

Member

:

08 CX-9 Sport

• Feb 3, 2010

• #5

no, i am nowhere near the rev limiter. for instance, one particular hill i will always shift down to 3rd when i am at about 35mph. it is probably close to 3k, but will not hold back much (not that it should bring me to a halt, but i should feel it). if i shift to 2nd the rpms will of course jump to 4-5k (have to do it again to be exact) but there will be no more engine braking then 3rd gear. its like its giving a slight bit of throttle. at first i thought it was the a/c compressor kicking on which will bump up the throttle a touch, but even with everything off its the same.

maybe i'll take a video. its very apparent when you watch the RPMs. at first it engine brakes just fine, and within 2 or 3 seconds it revs higher and does not hold back to the same degree.

Al

 

A

Al's Chop Shop

Member

:

08 CX-9 Sport

• Feb 3, 2010

• #6

JC-MP5 said:

Could it be that automatic cars almost always go into "neutral" when you aren't on the gas?

Click to expand...

i think you've never owned an automatic.....

they don't go into neutral. if you are comparing it to a manual it is quite different because the transmission is still 100% connected to the drive wheels in a manual, and an auto does have some slip. but it is definately not in neutral.


Al

 

J

jabba

Member

:

2008 MS3, 2008 CX-9

• Feb 3, 2010

• #7

I wonder if there's something happening with the torque converter? With the CX-9, it was the first time that I really noticed that RPMs can go up and down without changing gears, I think it's the TC engaging to give more umph. I usually only notice this when going up hills, maybe the reverse is true going down hills?

 

A

Al's Chop Shop

Member

:

08 CX-9 Sport

• Feb 4, 2010

• #8

i do notice the torque converter going in and out of lock, but i don't think that would be the case here. my truck will lock and unlock the torque converter and it engine brakes like none other no matter if its locked or unlocked. of course, its a v-8 so there is a lot more resistance. but this car is engine braking like a diesel (little to none at all).

Al