GenVibe - Community for Pontiac Vibe Enthusiasts

INTROI have been in correspondance with GM / Pontiac for several months working on a resolution to the Vibe cruise control multi-downshift issue. A general history of this problem can be found at the threads I will copy to the bottom of this post. A brief summary is as follows:THE PROBLEMWhen the 2006 Vibe (base automatic trans + other model years) is travelling in cruise with overdrive on, and reaches a hill, in many situations the car will downshift once followed by a second downshift to gain power to climb the hill. This second downshift bumps the RPM up to nearly redline - destroying fuel economy and your ears, along with a bit of your Vibe pride. This could be considered normal vehicle operation as many dealers would suggest; however, if in the same situation with cruise disengaged, it is possible to climb the same hill without a downshift at all, or at the very most just a single downshift. There is no need for the second downshift in cruise. What this poses is a need to reconfigure the way cruise reacts to certain driving conditions. In talking with GM / Pontiac, I have gotten them to acknowlege that it is actually a problem. However, they will not allocate techs to devise a correction to the PCM/ECM as too few Vibe owners have complained of the problem. This suggests that others have complained as I did, but not many. TAKE ACTIONWhat I want is for other Vibe owners, who are concerned and interested in this problem, to compose a letter that addresses your experiences with this problem. I want your to either postal mail or email the letter to me so I can send them all together to my contact at GM. I have attached a sample letter I used in talks with Pontiac / GM last summer. campb292@yahoo.comR Campbell4051 Otuna DrDorr, MI 49323http://forums.genvibe.com/zerothread?id=25489http://forums.genvibe.com/zerothread?id=18274http://forums.genvibe.com/zerothread?id=18494http://forums.genvibe.com/zerothread?id=17757

Attached files pontiacletter.doc (36 KB) 

it is not necessary to post the same thread in multiple forums.

SRLSY! ive seen this same thing like 4 other times.and besides, I was told NEVER to use cruise control on hills, it makes your engine work harder than just manually depressing the pedal yourself. sounds like someone has a case of the lazies!

Quote, originally posted by rch2005 »...........I was told NEVER to use cruise control on hills, it makes your engine work harder than just manually depressing the pedal yourself......................and how can using cruise control possibly make the engine work harder?

you missunderstood and read it wrong, using CC going UP A HILL i heard makes it work harder. i personally do not do this because I dont know if thats true or not.please read fully before asking! kthxbye

It's just not true.........total myth.

Quote, originally posted by djb383 »...and how can using cruise control possibly make the engine work harder? Well, the behavior described in the original post where the CC downshifts twice, once rather abruptly, and gets the engine up near redline doesn't sound particularly easy on either the engine or the transmission. Driving without CC, many drivers will choose not to force a downshift by flooring the gas pedal, but will instead let the car slow down a bit, especially if near the crest of the hill. Unlike the driver, the CC can't anticipate what's coming up so it will do whatever's needed to maintain the set speed even if the crest of the hill is only a few seconds away and it would make more sense to stay in the same gear and let the speed drop by a mph or two if necessary.

In traveling the West Virginia Turnpike between Charleston and Virginia in the Vibe I have noticed this problem and decided not to use the cruise control in the really hilly areas. All that downshifting makes me nervous. My V-6 T&C does not seem to have the same problem - at least not nearly to the same extent.