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Discussion Starter #1
I did a 5th gear change on Monday and it went well thanks to the information I found on the forums. As I expected I did loose cruise control in 5th gear, this was not a surprise as I had read in many posts and pages that this was likely. One thing that did surprise me was the loss of my AC anytime I accelerate in 5th gear now. Even a light acceleration causes the AC stop cooling then returns back to normal when cruising. This only happens in 5th gear and only started after the change. All other gears I can be full throttle and not have this issue.

Has anyone else had this issue and does it have anything to do with the gear change?
 

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Discussion Starter #2
I drove to Maryland today from SC, calculated fuel economy on the way up (through the mountains) and had a 6 mpg gain over my previous trips I have take in SC. Definitely worth doing the change even with the little inconveniences that come with it. Car pulls great at hey speeds.


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I did a 5th gear change on Monday and it went well thanks to the information I found on the forums. As I expected I did loose cruise control in 5th gear, this was not a surprise as I had read in many posts and pages that this was likely. One thing that did surprise me was the loss of my AC anytime I accelerate in 5th gear now. Even a light acceleration causes the AC stop cooling then returns back to normal when cruising.
Why did you change 5th gear for economy or something else? You shouldn't loose cruise control on 5th gear only.

You need to get your motor scanned (preferably with VAG-COM\VCDS) for any error codes logged in the ecu and post them, that will save a lot of guessing and check systems out.
 

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Discussion Starter #5
Actually, it is a know result that when changing 5th speed gear ratio, you are likely to loose cruise. I changed to increase fuel economy on the highway and it was a good choice. I have VAGCOM and regularly check it.

Most tunes have a fix for the cruise and is included with the tune. One I found it was an option.


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Discussion Starter #7
I ran across it when as I was looking into the upgrade. I believe while talking with my dad whom used to be a mechanic instructor, that it has to do with the computer expecting to see a certain RPM range and since the RPMs are so much lower, it disables the cruise to prevent possible damage. In short, the computer things something is wrong.

Post change I did have a 15%+ increase in hwy mileage. Looks like mixed mileage is going to be about the same or better as well.


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The ECU / Cruise Control seems to be programmed such that it compares engine speed, selected gear, and vehicle speed. Such, it is able to provide the cruise control function for selected speed in different gears. In case of a mismatch, cruise control will not work.
Cheers
 
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