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Old 07-01-2001, 09:08 PM   #1
mikemo
Scooby Newbie
 
Member#: 7627
Join Date: Jun 2001
Location: Palm Harbor, FL
Vehicle:
93 L Wagon
Blue (ish)

Default AT Power Mode

I'm trying to get used to my new (to me) MY93 Impreza wagon FWD, AT. The manual says that when I get on the throttle that the trans should switch to "power mode" and the light on the dash should come on.

The I know the light works because it comes on when I first start the car. However, no matter how hard I drive the light never comes on. Can anyone give me an idea as to how easy it is to get in to "power mode".

I guess I'm interested because the car is a bit pokey, especially with the a/c on.

Thanks!
Mike Mo
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Old 07-01-2001, 10:18 PM   #2
SubyTechMaster
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Member#: 4423
Join Date: Feb 2001
Location: Placerville, CA USA
Vehicle:
'04 08 Tribeca, SVX
Gold, Maroon

Default

Power-mode is the same as a passing-gear, or downshift. It will come on when; according to how fast you depress the accelerator causing the A/T to downshift, also depending on what gear the A/T is in. If the A/T is in 1st gear of course it can't downshift. Likewise, if you are going over 55-60mph, it won't downshift into 2nd. If you are cruising at 50mph and the A/T is in 4th, you then open-up the throttle suddenly (like a passing situation) it will downshift to 3rd and the power light will come on.

Also, the Power light is used to comunicate a fault. If when you 1st start the engine the Power light flashes 16 times and then turns off, it means you have a trouble code in the TCU. If you have a code this could prevent you from getting into Power-mode.
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Old 07-01-2001, 11:47 PM   #3
garface
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Member#: 1581
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Chapter/Region: Tri-State
Location: yonkers, ny
Vehicle:
MY00 RS/STi7
MY01 RS Both Silverthorne

Default

Try hitting the accelerator twice real quick.
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Old 07-02-2001, 03:16 AM   #4
bratmantlz
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Join Date: Dec 2000
Chapter/Region: RMIC
Location: colorado springs colorado usa
Vehicle:
88 626 Turbo
white

Default

and dont use the a/c if you dont want the car to be pokey it drains the energy out of hte engine.
Brat
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Old 07-02-2001, 07:58 AM   #5
mikemo
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Join Date: Jun 2001
Location: Palm Harbor, FL
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93 L Wagon
Blue (ish)

Default

Just for fun, before I started her this morning, I pumped the accelerator 10 times all the way to the floor and back, in hopes of wiping clean the TPS. I don't know if that is what made the difference, but the power light comes on now and the trans downshifts. I guess I should replace the TPS.
This was an 11k miles "old guy" car and probably has never seen full throttle.
And yes, the A/C REALLY slows this car down, but living in Florida it is a necessity.
Thanks for the advice!
Mike Mo
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Old 07-02-2001, 10:07 AM   #6
Clegg
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Chapter/Region: MWSOC
Location: Denver, CO
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2008 VW R32 #3858
Blue

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I havent noticed a drain on the performance or MPG when running the A/C in my 02 2.5RS. I mean there are more noises then ( of the fans kicking in and just the compressor running) but besides that its still got some nice power. it doesnt drop the power off to nothing like it does on some smaller displacement engines.
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Old 07-02-2001, 11:45 AM   #7
bratmantlz
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88 626 Turbo
white

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oh you do loose some mad power and mpg enough to make a difference... sucks i do understand the a/c in fla thing its hot there but nice hot..
Brat
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Old 07-02-2001, 12:12 PM   #8
adam@stonehill.edu
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2000 Impreza 2.5RS
Dirty White

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I'd have to agree with Clegg. I have a MY2000 RS and you don't notice much of a difference with the AC running. The idle jumps about 300 RPM higher and fans kick in and stuff but not much of an acceleration loss.

I guess technology is improving

- Adam
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Old 07-02-2001, 12:17 PM   #9
Clegg
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Blue

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well I know before it was said A/C will cut MPG 1/3 on older cars or real small displacement cars ( 1.6L or less)

But recenetly a BMW rep was saying how current A/C compressors only take 1/10th of the drain on a car that the ones years back did. Also with many cars shrinking it doesnt take as much of a compressor to cool the whole inside of the car.

I dunno, I just nodd my head up and down and say "sure". But when I have the A/C on I feel almost NO drop in performance. heck even on my Inline 4 2.4L Dodge Stratus I felt the A/C compressor alot! ( I would always kill the A/C when i was about to race off the line... but in my scooby I rarely ever need to).
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Old 07-03-2001, 07:51 AM   #10
mikemo
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Location: Palm Harbor, FL
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93 L Wagon
Blue (ish)

Default

Here is an update. I was having trouble getting the AT to switch in to "power mode". It seemed intermittant. At first I thought my TPS was flaky. Just for fun I followed the advice of one of the posts and "released and pressed" the throttle. It drops in to power mode every time I do this. If I go full throttle from a stop it will not drop in to power mode unless I partly release then depress the throttle.

Is this normal?

BTW, I'm getting used to driving the scooby. I changed out the spark plugs last night. Easy job, only took about 45 minutes (I'm slow). It didn't make much of a difference in the way it drove, but the original plugs only had 12k miles on them (NGK) and they looked fine. I've got a slightly rough idle, while in drive at a stop with the A/C on. Kind of a low rumble. If I drop it into neutral it runs _smooth_. Is this a real problem or am I chasing my tail? The A/C works great, even here in Florida it will freeze you out.

Also, I'm getting around 26-27 MPG. Mixed City and highway. Does this sound about right (1.8L, AT, A/C sometimes)?

Thanks for the advice.
Mike M.
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Old 07-03-2001, 09:29 AM   #11
micah
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Default

Note that the transmission (if everythings working okay) will always downshift on full throttle if it can, power mode or not. However when it goes into "power mode" it assumes you are driving hard and it will hold the lower gear longer, and raise your shift points, for as long as it's in power mode. I think it's based at least in part on how quickly you hit the gas. It should come on with a very fast flooring of the gas.

cheers
mbs
'00 mr2
'92 svx
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Old 07-06-2001, 08:28 AM   #12
mikemo
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Member#: 7627
Join Date: Jun 2001
Location: Palm Harbor, FL
Vehicle:
93 L Wagon
Blue (ish)

Default I figured it out now.

Ok, this has been bugging me, but I've got it figured out now.

Sometimes it would go into "power mode", and sometimes it wouldn't. I thought that the TPS was bad. Come to realize that the TCM does NOT care where the throttle is, but it looks at how FAST the throttle changes.

So, if you depress the throttle all the way to the floor it may not go into power mode, but if you push the throttle QUICKLY it will instantly go into power mode. I don't thrash the car, so I rarely pushed the throttle quickly, I would just go smoothly to full throttle.

Whew, I feel better ;-)

Thanks for the help.
Mike M.
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Old 07-06-2001, 09:23 AM   #13
Max Umbarger
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Location: Colorado Springs
Vehicle:
2006 FXT
RBP

Default Thrash it

You should thrash it, it will run better I have the same year, and engine, and it's put up with 155,000 miles of 100% throttle!!
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