The change of 1st jumps when you traction Hyundaih1

Well I have a problem with a Hyundai H1 TDI. The problem is when the vehicle parts first

Hi. You didn't say if it's a manual or automatic transmission, but I'm guessing it's manual. You'll have to take it apart because the problem is with the 1st and 2nd gear synchronizer. Some people grind the teeth and replace the brass rings, while others replace the entire synchronizer.

I had a similar problem with my '96 Hyundai Accent GLS. I had the transmission fluid changed, but I didn't realize they put in a very thick fluid. They thought that because of the car's age, it was better to use that type of fluid. I started having problems with the transmission; the gears weren't shifting smoothly, and it was making a terrible noise. I took it back and had the fluid changed to a lighter multigrade fluid, and the transmission started working much more effectively again. Have you ever had your transmission fluid changed?

I completely agree with Gilberto's comment... it's the first and second gear synchronizer. I know this because I study automotive mechanics, and when the synchronizer wears out due to poor lubrication or using the wrong oil, it throws the gear out of play, in this case, into neutral. I hope this helps.

I had a similar problem with my Fiat 147. It started acting up in 3rd gear, then 1st and 2nd, the latter problems appearing within a few days. The suggestions were to open the transmission and replace the synchros, check the linkage, or replace the transmission mount. Checking the linkage seemed the best option, so I did it myself. I found the parts were new because the previous owner had replaced them. The linkage rubber kit didn't work for me, as the components didn't match the parts I needed to replace. I noticed some play in the piece that connects the linkage to the transmission's drive shaft. I couldn't find a brass or rubber bushing on the market that would fit the eye of the transmission shaft. Finally, I used a piece of rubber that I drilled and machined to allow the pin securing the connecting piece to pass through. I cut strips of bicycle inner tube to fill the wear gap at the base of the connecting piece (where the pin goes in). This solved my problem; the transmission works fine, and the gears shift smoothly. The oil is important; in my case, I use 80W90 oil. You shouldn't use oil with a higher viscosity than recommended. I hope this helps.