My 1999 vr6 vw jetta, everytime i shift into a gear the rpms rises and dropps down while the accleration is very slow kind of like the gears are slipping im not sure whats wrong it smells like my clutch is burning, do i need a new clutch or just an adjustment

The Check Engine Light is on? Did you read the DTCs.

The second link has the answer, the first link says it is a known issue. It is times like this you need the Dealership or a good auto electrician.

Transmission won't shift to third until temp rise

ClubLexus https://www.clublexus.com > forums > 713188-transm...
Apr 1, 2017 - Transmission won't shift to third until temp rise ... The solution is to drive slow and keep rpms at 2.5k and 3k at max till the engine and transmission warm up.
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Owner of Lexus RX300 with 182000 miles. Recently the ...

JustAnswer https://www.justanswer.com > lexus > 3wsxt-lexus-rx3...
Aug 22, 2010 - Recently the transmission won't go into overdrive. Stays in 3rd gear like when you press the o/d button to do so. When car is cold (live in ...
1 answer · Top answer: Hello and thank you for using just answer! The check engine light is on correct?

https://www.google.com/search?q=Lexus+RX300+will+shift+into+overdrive+once%2C+and+after+slowing+down+it+won%27t+go+past+3rd+gear

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I'm confused, is this a manual or auto transmission? Does it have tiptronic or no?

Yes it is. or the pressure plate. you get both when you replace the clutch.

GO UNDER CAR ON TRANSMISSION LOOK FOR A PLUG PULL IT OUT STICK YOUR PINKIE FINGER IN THE HOLE IF NO GEAR OIL ON THERE THEN GET GEAR OIL NOT TRANSMISION FLUID AS STICK SHIFTS USE GEAR OIL JUST PUT IN THAT HOLE TILL OVER FLOW PLUG IT BACK UP THEN GO FROM NUTRAL TO HIGH GEAR WHILE CAR IS NOT ON HOP THIS HELP IF NOT IT COULD BE CLUTCH BEARING IS SHOT THATS NOT A DO IT YOUR SELF PROBLEM UNLESS YOU OWN A GARAGE LOL

the clutch may burn out on those gear, check the fluid if it smell burn

Inside the transmission case above the pan. You should probably let a transmission mechanic handle this one.

you might have bad ground to transmision that happen to my 01 jetta were it would just kind of rmp no shifting gears dealer said it was bad ground to trany

From the sounds of it you need to have your transmission rebuilt, there is no quick fix for a fault in one gear. As far as the tapping noise goes quite often a oil change is all that is required to cure it.

You'll have to get it checked. Its going into limp mode. When this happens you have third gear and reverse. Its to get you somewhere to get it fixed. You can damage the tranny worse driving a lot while its like that

I have a1998 VW jetta vr6 glx with the same problem and living in New England it gets really cold, but i did some research and it worked.... With the car in neutral and the E-break engaged, reach down and pull up on the clutch pedal, thus "resetting" the tension in the cable, it will be a bit higher on your foot and the release/engage point will be higher as well but i did this when it was 10*f and i could not get any gear, after pulling up on the clutch, shifts with ease,,,, such a relief