80mph in first??? - somethings gotta be wrong - Transmission Forum

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80mph in first??? - somethings gotta be wrong
Saturday, January 07, 2006 8:13 AM
Hey,
So background info:
2004 Sunfire
Automatic

K, so one day I noticed that when I put my "shifter" down to 1 and gave it some gas, it would shift. I thought, well thats wierd. I also noticed that I could put it down to the 1 when I was going like 35. Well I told Adam (NJHK) and he said it shouldn't do that and that it should hit the rev limiter when I get too fast in first gear. He didn't believe me that it was happening so I told him I would make some videos of it.
This first one is me on the freeway. I put it to the 1 at about 15 and well u'll see what happens.
Video 1
Then I couldn't tell if that time it shifted so I tried it another time started at about 30 mph and just floored it. Sorry for the jolt down of the camera but there was an unusually powerful "kick". If you listen you can hear it shift.
Video 2
So my question is, why does it do this. I would think that it would just hit a rev limiter but idk. I was also thinking that maybe the computer takes into account your throttle position, speed, and the gear u have selected so like if ur flooring it in first it will shift for you, and if like ur brakes stopped working and you shifted down to slow down, it would see the throttle was closed and actually put you into that gear. IDK. This might be a stupid question but any help would be appreciated.

Thanks,
-Seth




Re: 80mph in first??? - somethings gotta be wrong
Saturday, January 07, 2006 6:03 PM
nope mines stays in first and hits the limiter also no matter what i do



The one, the only, ME.
Re: 80mph in first??? - somethings gotta be wrong
Saturday, January 07, 2006 10:33 PM
04eco (theN/Aautoone) wrote:nope mines stays in first and hits the limiter also no matter what i do


Same here.

I wouldn't worry about it though...not like you need to shift your car anyways.



www.kronosperformance.com / 732-742-8837

Re: 80mph in first??? - somethings gotta be wrong
Sunday, January 08, 2006 9:03 AM
I don't know what the problem is but there is no way your in first gear in the first video. It's impossible. Maybe it has something to do with your console being torn apart. What are you doing in there anyway.




Re: 80mph in first??? - somethings gotta be wrong
Sunday, January 08, 2006 11:00 AM
I can't really tell from the videos, are you sure the car shifted? When you're in first gear the tranny shouldn't shift to another gear.

Also, I hope you don't shift your auto while driving, that's not exactly great for the tranny.



Blown.
Re: 80mph in first??? - somethings gotta be wrong
Sunday, January 08, 2006 2:43 PM
your linkages must be off and your car says 1st but your prob in 2nd.


1993 Pontiac Sunbird 2.0 N/A 200+ HP this summer 2006
Team Zero
MMK Tuning
teamzero5.tripod.com
Re: 80mph in first??? - somethings gotta be wrong
Sunday, January 08, 2006 5:06 PM
NJHK (The JBO Negro) wrote:
04eco (theN/Aautoone) wrote:nope mines stays in first and hits the limiter also no matter what i do


Same here.

I wouldn't worry about it though...not like you need to shift your car anyways.



Same here too!!!

Exactly...you don't need to shift...thats why I can drive around town and drink a coffee at the same time, without using my knees anymore.





"I know not with what weapons World War III
will be fought, but World War IV will be fought
with sticks and stones."
-Albert Einstine-
Re: 80mph in first??? - somethings gotta be wrong
Sunday, January 08, 2006 7:08 PM
I think its a safety feature of the tranny by doing that, with it shifting electrically. I think i recall reading about that once on here.


Re: 80mph in first??? - somethings gotta be wrong
Sunday, January 08, 2006 7:12 PM
Here's a serious answer for your question (I'm not joking)

"The car is smart. The driver is stupid. The smart car KNOWS the driver is stupid."

That's all there is to it.





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Re: 80mph in first??? - somethings gotta be wrong
Sunday, January 08, 2006 10:17 PM
Caviboy90 wrote:your linkages must be off and your car says 1st but your prob in 2nd.

I wouldn't even have the slightest idea on how to check for that.

Jonathan French (minitransam) wrote:I don't know what the problem is but there is no way your in first gear in the first video. It's impossible. Maybe it has something to do with your console being torn apart. What are you doing in there anyway.

I'm thinking my car was in 3rd. I'm painting it - its been out for like 6 months - lol. I had plans then lost job and wasn't able to do them until now and I didn't want to put it back in. The wires are for a shifter position thing I was workin on for s post someone had.

Filip (The Polish Kid) wrote:I can't really tell from the videos, are you sure the car shifted? When you're in first gear the tranny shouldn't shift to another gear.

Also, I hope you don't shift your auto while driving, that's not exactly great for the tranny.

Nope I don't. I just wanted to see one day and i noticed it shifted.

Ender_Wiggin wrote:I think its a safety feature of the tranny by doing that, with it shifting electrically. I think i recall reading about that once on here.

That's what I was thinking.

Mr. Pute wrote:Here's a serious answer for your question (I'm not joking)

"The car is smart. The driver is stupid. The smart car KNOWS the driver is stupid."

That's all there is to it.

LOL - see above answer.

I was thinking it might also be because I'm using a PCM/ECM (whatever u wana call it - the computer in the engine bay) that was from another car. But that shouldn't really make a difference I think-idk.

-Seth



Re: 80mph in first??? - somethings gotta be wrong
Sunday, January 08, 2006 11:26 PM
Whatever you're trying to achieve.... which I don't know what the heck it could possibly be.... you're going to end up killing the poor transmission doing that.






Re: 80mph in first??? - somethings gotta be wrong
Monday, January 09, 2006 12:01 AM
Lenko, John Lenko wrote:Whatever you're trying to achieve.... which I don't know what the heck it could possibly be.... you're going to end up killing the poor transmission doing that.

One day I noticed it and so I got a vid so I could show u guys what i was talkin about. I don't go out and do this regularly at all.

-Seth



Re: 80mph in first??? - somethings gotta be wrong
Monday, January 09, 2006 12:05 AM
Quit playin with your stick lol



www.kronosperformance.com / 732-742-8837

Re: 80mph in first??? - somethings gotta be wrong
Monday, January 09, 2006 9:56 AM
yeah.. ive done that before.. and if im in 3rd and going more than 70 it wont down shift to 2nd and i think 30 it wont shift down to 1st.. its a safety feature to keep u from doing something stupid..


here comes the boost!
Re: 80mph in first??? - somethings gotta be wrong
Monday, January 09, 2006 10:32 PM
^^^^^ thats what im thinking were you going faster in a higher gear and then shifted it down to 1st? cause like he said if your driving around in "D" doing 80 and throw it down to first it wont down shift itll stay in 3rd at 80 though the position is 1st



The one, the only, ME.
Re: 80mph in first??? - somethings gotta be wrong
Tuesday, January 10, 2006 3:47 PM
man if you were going 80 in first youd be spinnin like insane rpms like 35000 rpms lol and your tach looks like its normal


http://www.cardomain.com/ride/2090440

Re: 80mph in first??? - somethings gotta be wrong
Tuesday, January 10, 2006 5:58 PM
here's your answer.

when you were doing 35 or 15, your car wasn't in first gear. it was at whatever previous gear it was at. the car doesn't downshift until there's a load on it (so if you let off the gas, it hasn't shifted yet, until you hit the gas again). you were probably in 3rd gear or so, because 80 mph in fourth would be 3000 rpms.

that said, the electronic 4 speed has a safety feature IN CASE for some stupid reason you try to engage it into a lower gear. so if you're doing 60, and throw it in first, its not gonna change because it knows its going WAY too fast. yes, computer > driver.

and yes, this has been partially discussed before



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Re: 80mph in first??? - somethings gotta be wrong
Tuesday, January 10, 2006 9:48 PM
Viper98912 wrote:and yes, this has been partially discussed before

What post, do u remember??? or something I could search for that would bring it up???

I took some of these replies into consideration so I did another experiment. Stopped at a red light COMPLETELY and moved the shifter to 1. Gave it gas when the green light came, I was going onto the freeway and it shifted just like it was in drive. This should have hit a rev limiter though right??

-Seth



Re: 80mph in first??? - somethings gotta be wrong
Wednesday, January 11, 2006 4:59 PM
The computer is deciding what the trans is doing.

You are only telling the computer what you would like it to do.

The computer is programmed not to downshift to a selected gear if the driver moves the shifter to that gear and the resulting engine rpm would be to high for the engine, or too high for any real usable travel.

At this point "the computer is smarter than the driver". It knows the car will be damaged if it does what is being requested to do by a driver who lacks the wits to know that putting a car in 1st at 80mph will destroy the engine and likely the trans, too.

Also along the same lines, driving a car down the street at exactly "redline" will also damage the engine. GM does program the car to upshift when you do it. THis is because driving like that serves no purpose except to cause damage. Again, who is acting smarter in this instance...the driver or the computer??

Some cars will hit the rev limiter. This is because the shift speed is governed by the output speed of the trans and the engine limiter is based on engine rpm.
The torque convertor is a less than perfect invention. 2 "identical" ones will have slightly different stall speeds, and so on, everytime. Also with more power (mods) the torque convertor will slip a little more than with less power.

With the torque convertor being the slip joint in the middle, some cars will hit the rev limiter because their convertor is a little looser. They hit the limiter because the trans output speed is slightly lower at that particular RPM. Other cars will shift because their convertor is a little tighter and the output speed hit the gear limit in advance of the rev limiter.


So in the end...
Yes your car is working properly.
No your car is never ever in 1st gear at 80mph.
Doing dumb things with your shifter isn't going to make do damage to itself.




sig not found
Re: 80mph in first??? - somethings gotta be wrong
Saturday, January 14, 2006 9:16 AM
Thanks for all the help everybody.
Yesterday I went to the junk yard and managed the find the PCM from my donor car. I plugged it in, let it relearn itself and then took it for a test drive. I put it down to 1, and the revs went up just like they should have. So now it works like it should.
The only thing that i can think that happened to my old pcm is when i took it to GM to get the tranny fluid checked, the dude plugged his tech2 (or whatever it is) in and reset the shift count. Well i don't think that was all he was doing but there is no way of telling.

-Seth



Re: 80mph in first??? - somethings gotta be wrong
Monday, January 16, 2006 3:59 PM
Caviboy90 wrote:your linkages must be off and your car says 1st but your prob in 2nd.

im going with caviboy90 i think its your linkages.
but @!#$ like this is why i bought a 5spd.
my car shifts when i say like a good little bitch


Dark for fear of failure
An inner gloom as wide as an eye and fermenting
Roiling hate
Death gripped my veins
Unveiling rancid petals
Flowering forth foul nectar
The space between a blink and a tear
Death blooms.-mudvayne

Re: 80mph in first??? - somethings gotta be wrong
Monday, January 16, 2006 5:52 PM
streetfighterz wrote:
Caviboy90 wrote:your linkages must be off and your car says 1st but your prob in 2nd.

im going with caviboy90 i think its your linkages.
but @!#$ like this is why i bought a 5spd.
my car shifts when i say like a good little bitch

wizkiddrummer wrote:Yesterday I went to the junk yard and managed the find the PCM from my donor car. I plugged it in, let it relearn itself and then took it for a test drive. I put it down to 1, and the revs went up just like they should have. So now it works like it should.
-Seth

I found it was my PCM

-Seth



Re: 80mph in first??? - somethings gotta be wrong
Wednesday, January 18, 2006 1:17 AM
Next time a big give away...
1st and 2nd gear will display a "Track Off" light on the speedo , your not in first or 2nd.



Re: 80mph in first??? - somethings gotta be wrong
Wednesday, January 18, 2006 1:48 AM
Your transmission has a safety valve in it based on line pressure and engine load (vacuum) called the modulator valve that diverts line pressure to make the transmission upshift for you if you decide that you don't like your engine anymore and want to rev to the moon in 1st gear. The only thing that it wont do if I recall correctly is go into Lock-up unless you are in drive.

Basically.. leave it in drive.



Cardomain|Myspace

Re: 80mph in first??? - somethings gotta be wrong
Wednesday, February 08, 2006 12:46 AM
with my car top speed in:
1st - 41mph
2nd - 73 mph
3rd - don't know (governor)

If you leave it in 1st or 2nd and accelerate it will just bang off the rev limiter. It won't shift up from gears. If you are going 80 and put in first it will still be in third. It's about 6 mph lower than the numbers I listed above for it to actually downshift. It will downshift at about 66 then 35 for first.
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