Recommendation: When replacing the tension roller without removing the timing belt, there is a risk of the belt jumping over the pulley teeth, which will lead to a shift in the valve timing. Therefore, before loosening the belt tension, align the mark on the camshaft pulley with the protrusion on the rear belt cover (see Fig. "Timing Belt - Replacement"). After installing the roller, the mark should not shift.
2. Loosen the tension roller mounting nut (see "Timing Belt - Checking Condition and Adjusting Tension") and turn it completely away.
3. Remove the roller from the pin, keeping the belt taut.
Warning! There is a spacer sleeve installed on the tension roller mounting stud, do not lose it.
(The original is on the portal: VAZbook)
4. Install a new roller on the stud and secure it with a nut and washer, preventing the belt tension from slackening.
5. Adjust the tension of the timing belt (see "Timing Belt - Checking Condition and Adjusting Tension").
6. Install the front timing belt cover.