RAV4 Transmission Behavior Problem
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From: C. E. White on 25 Jun 2007 09:58 Vehicle - 2007 RAV4 FWD (2WD) 4 cylinder, automatic. Problem - When the cruise control is used, the transmission downshifts/upshifts frequently when small inclines are encountered. If the cruise control is not used, the transmission does not shift in the same manner on the same inclines - in other words - if you maintain speed manually, the transmission does not hunt back and forth on minor inclines, but it does do this if the cruise control is used. Seems weird, but the behavior is so annoying my SO won't use the cruise control in many situations. Ed
From: Jeff Strickland on 25 Jun 2007 10:45 The Cruise reacts differently than your foot. Since it takes a bit longer to realize the changing conditions, it has to apply more gas to get the Set Speed back, and this makes a downshift out of OD. The speed returns and the shift back OD but the car can't keep the speed because the gear is wrong, so it downshifts out of OD again, and the process repeats. You can take control by shifting out of OD until you get to the top of the hill. The Cruise does not apply small amounts of gas as you do with your foot. It likes to apply full gas when if needs gas, and that causes a downshift. "C. E. White" <cewhite3(a)removemindspring.com> wrote in message news:467fca44$1(a)kcnews01... > Vehicle - 2007 RAV4 FWD (2WD) 4 cylinder, automatic. > Problem - When the cruise control is used, the transmission > downshifts/upshifts frequently when small inclines are encountered. If the > cruise control is not used, the transmission does not shift in the same > manner on the same inclines - in other words - if you maintain speed > manually, the transmission does not hunt back and forth on minor inclines, > but it does do this if the cruise control is used. Seems weird, but the > behavior is so annoying my SO won't use the cruise control in many > situations. > > Ed >
From: C. E. White on 25 Jun 2007 11:08 "Jeff Strickland" <crwlr(a)verizon.net> wrote in message news:EyQfi.679$w2.415(a)trnddc01... > The Cruise reacts differently than your foot. Since it takes a bit > longer to realize the changing conditions, it has to apply more gas > to get the Set Speed back, and this makes a downshift out of OD. The > speed returns and the shift back OD but the car can't keep the speed > because the gear is wrong, so it downshifts out of OD again, and the > process repeats. > > You can take control by shifting out of OD until you get to the top > of the hill. > > The Cruise does not apply small amounts of gas as you do with your > foot. It likes to apply full gas when if needs gas, and that causes > a downshift. Thanks for the reply. I understand what you are saying, but the behavior is not normal (at least in my opinion). I am not talking about significant grades, just minor ones (like on I-40 from Raleigh to Wilmington NC). I've driven the same route in multiple vehicles and never had one react like the RAV4. I am thinking the control program is bad. The PCM actually controls the throttle position and the transmission gear selection. It sure seem like it could do a better job of controlling the situation. I was hoping there was a PCM code update that would fix this. My SO won't use the Cruise Control in may cases because it works so poorly. I have encouraged her to take it to the dealer, but she thinks that would be a waste of time. If my Ford acted like her RAV4, it would be at the dealer today. There is no way I would put up with the behavior (but then I would never have been satisfied with a I-4 RAV4). Ed > "C. E. White" <cewhite3(a)removemindspring.com> wrote in message > news:467fca44$1(a)kcnews01... >> Vehicle - 2007 RAV4 FWD (2WD) 4 cylinder, automatic. >> Problem - When the cruise control is used, the transmission >> downshifts/upshifts frequently when small inclines are encountered. >> If the cruise control is not used, the transmission does not shift >> in the same manner on the same inclines - in other words - if you >> maintain speed manually, the transmission does not hunt back and >> forth on minor inclines, but it does do this if the cruise control >> is used. Seems weird, but the behavior is so annoying my SO won't >> use the cruise control in many situations. >> >> Ed >> >
From: Dave Dave on 25 Jun 2007 11:54 my 06 camry 4 cyl does the same thing. just a slight grade on the interstate will cause it to downshift. love toyotas . they last forever but this is one thing that is anoying. the dealer will tell you this is normal. which it is for toyotas. theceuse control will matain the speed but will upshift and downshirt all the time. other than that how do you like your RAV 4?
From: Hachiroku ハチロク on 25 Jun 2007 12:47
On Mon, 25 Jun 2007 11:08:27 -0400, C. E. White wrote: > > "Jeff Strickland" <crwlr(a)verizon.net> wrote in message > news:EyQfi.679$w2.415(a)trnddc01... >> The Cruise reacts differently than your foot. Since it takes a bit >> longer to realize the changing conditions, it has to apply more gas to >> get the Set Speed back, and this makes a downshift out of OD. The speed >> returns and the shift back OD but the car can't keep the speed because >> the gear is wrong, so it downshifts out of OD again, and the process >> repeats. >> >> You can take control by shifting out of OD until you get to the top of >> the hill. >> >> The Cruise does not apply small amounts of gas as you do with your foot. >> It likes to apply full gas when if needs gas, and that causes a >> downshift. > > Thanks for the reply. I understand what you are saying, but the behavior > is not normal (at least in my opinion). I am not talking about significant > grades, just minor ones (like on I-40 from Raleigh to Wilmington NC). I've > driven the same route in multiple vehicles and never had one react like > the RAV4. I am thinking the control program is bad. The PCM actually > controls the throttle position and the transmission gear selection. It > sure seem like it could do a better job of controlling the situation. I > was hoping there was a PCM code update that would fix this. My SO won't > use the Cruise Control in may cases because it works so poorly. I have > encouraged her to take it to the dealer, but she thinks that would be a > waste of time. If my Ford acted like her RAV4, it would be at the dealer > today. There is no way I would put up with the behavior (but then I would > never have been satisfied with a I-4 RAV4). > > Ed Increase your speed, or take off the OD. Generally, on my Toys, I have found that this behaviour stops at speeds over 65 MPH. Since most cops don't bother with you until you're over 70MPH, I set it to 68 and the problem goes away. > > > >> "C. E. White" <cewhite3(a)removemindspring.com> wrote in message >> news:467fca44$1(a)kcnews01... >>> Vehicle - 2007 RAV4 FWD (2WD) 4 cylinder, automatic. Problem - When the >>> cruise control is used, the transmission downshifts/upshifts frequently >>> when small inclines are encountered. If the cruise control is not used, >>> the transmission does not shift in the same manner on the same inclines >>> - in other words - if you maintain speed manually, the transmission >>> does not hunt back and forth on minor inclines, but it does do this if >>> the cruise control is used. Seems weird, but the behavior is so >>> annoying my SO won't use the cruise control in many situations. >>> >>> Ed >>> >>> >> |