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Discussion Starter #1
Why is it that in 4th gear my rpm will drop then pick back up? Its a e-shift.. but say on the free way im trying to pick up speed and while in fourth i can hear my rpm drop.. i decided to get off and get on the freeway again and watch my rpms in 4th and I DO see it drop a little and get back up.. is this normall?

Chris
 

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chris, I get the samething in 3rd and 4th. it drives me nuts and I have yet to find the problem. anyone know?
 

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Discussion Starter #3
ahh i want to know whats wrong.
 

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Well when you choose 4 in e-shift mode... it doesn't mean your car is actually in fourth gear. It means the car will go to a maximum of 4th gear.

Is it possible that your car is actually in 3rd gear... and the rev drop you see is it shifting from 3rd to 4th? Then the revs climb as your car continues to accelerate in 4th?
 

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Discussion Starter #5
Well when you choose 4 in e-shift mode... it doesn't mean your car is actually in fourth gear. It means the car will go to a maximum of 4th gear.

Is it possible that your car is actually in 3rd gear... and the rev drop you see is it shifting from 3rd to 4th? Then the revs climb as your car continues to accelerate in 4th?
I know that, its not like im in 4th gear and pushing down the pedal.. im just getting on the freeway going faster with a nice steady pedal push and you can hear it in 4th goung up in rpms then drops very slightly and goes back up.. didnt notice it too much untill i got my exhaust because the sound is very distinctive..

anyone know?
 

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Well... is it the gear changing?
 

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Nothings wrong. It's a feature called torque converter lockup.

The ECU will "lock" the torque converter via an actuator at light loads to prevent natural torque converter slip. This increases efficiency and gas mileage.

It's a feature that is present in almost every automatic car.
 

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That causes a noticeable rpm drop?

That's funny... I never notice it. The only time I see revs climbing... then drop... then continue climbing is during a gear change. It happens quickly tho.
 

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im having the same issue with my car.
My case will be that i step on the gas from 2nd till 4th and i can see the rpm drop at 3.5rpm then goes up.
any input on this?
this have never happened before.
 

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Discussion Starter #10
Nothings wrong. It's a feature called torque converter lockup.

The ECU will "lock" the torque converter via an actuator at light loads to prevent natural torque converter slip. This increases efficiency and gas mileage.

It's a feature that is present in almost every automatic car.
Thanks for your information. So this happens only on light loads? So if I went WOT would it still do the same? Because i think it still does that under wot.. not 100 percent sure. ill check sometime
 

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I think I misread the first time. So you're saying the rpm kinda hangs or drops while accelerating? Is there an rpm that this is happening at?
 

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It's normal when shifting gears up because there is a lag when shifting gears. I guess the best example I can give is when your riding a 10 speed bike with 1st gear being the easiest to move from a stop and then as you build speed you change gears to go faster, but as you switch gears you don't take off right away you still have to build more momentum and then when you want to go even faster you change gears again with each gear getting bigger and with larger revolutions. Try starting on first gear on your 10 speed and when you start moving click it to second gear and you will feel that lag time it takes you to get second gear rolling to third.

Depending what speed you are at when shifting will also affect the rpm drop. Next time you hit the freeway on ramp at a stop shift to e-shift and step on it 3/4 on the pedal and wait till you feel the gear hit the true second gear and when your rpm hits close to 6 rpms shift to 3rd and then 4th when the rpm hits close to 6 rpms then 5th. By then you should see the rpms go down a little everytime you shifted, but should be at 65-70 mph already. If you are stepping on the gas hard around 3rd going to 4th your rpm shouldn't drop as much.

Basically what your asking is normal. By the way at what rpm are you shifting at e-shift? and at what speeds?
 

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It is not when I am changing gears, it is already in 4th gear. e-shift or auto, doesn't matter. It gets to about 3500 rpm (floored) and kinda hangs or goes down in rpm for about 3 seconds and it goes like normal. it always happens in 4th gear, sometimes in 3rd. speed, I'd say anywhere from 75-80ish
 

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crazy mikey im having the same problem
do u have any aftermarket headers?
i was planning on checking my sparks or do a compression test
 

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Discussion Starter #16
It's normal when shifting gears up because there is a lag when shifting gears. I guess the best example I can give is when your riding a 10 speed bike with 1st gear being the easiest to move from a stop and then as you build speed you change gears to go faster, but as you switch gears you don't take off right away you still have to build more momentum and then when you want to go even faster you change gears again with each gear getting bigger and with larger revolutions. Try starting on first gear on your 10 speed and when you start moving click it to second gear and you will feel that lag time it takes you to get second gear rolling to third.

Depending what speed you are at when shifting will also affect the rpm drop. Next time you hit the freeway on ramp at a stop shift to e-shift and step on it 3/4 on the pedal and wait till you feel the gear hit the true second gear and when your rpm hits close to 6 rpms shift to 3rd and then 4th when the rpm hits close to 6 rpms then 5th. By then you should see the rpms go down a little everytime you shifted, but should be at 65-70 mph already. If you are stepping on the gas hard around 3rd going to 4th your rpm shouldn't drop as much.

Basically what your asking is normal. By the way at what rpm are you shifting at e-shift? and at what speeds?
The drop isnt happening form "shifting" its whle riding in 4th gear going to a certain rpm to shift.. if thats what you are tryign to tell me
 

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The drop isnt happening form "shifting" its whle riding in 4th gear going to a certain rpm to shift.. if thats what you are tryign to tell me
Hmmm, no I don't have that problem. How is the compression in your engine? no leaks or anything right? Plugged filter?
 

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Discussion Starter #18
Dont know how to check my compression or if theres any leak.. i dont have that much knowledge on the engine.. just basics.. arent there compression tests?
 

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I have a similar problem like that too but it's not the the rpm is dropping it seems I lose power from 3.5k to about 4.5k rpm. When I floor off the on ramp it will pull until when it reaches 3.5k there's no power and slowly creeps up to 4.5 k then a push and then shift to next gear.
 

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i know what your talking about. I have the samething on my 01'. I think its a common thing on 01's. its much more distinct w/exhaust. I would call it a "hang up" type feeling. this is when i really notice it. If your on the freeway doing say 60-70 and then punch it, the trans drops in 4th. when your in 4th gear the rpms start climbing and then around 3.5 like u said it "hangs up" for a sec. It just almost as if u let off the gas like 1/4in and then got back on it
 
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