Ac check engine

1994 Jetta 2.0 manual. When I turn the AC on, car loses power and check engine light turns on. turn the AC off, everything is fine. will change both temp sensors today, as I am hoping for a cheep fix.

Throwing parts at it rarely works.

When the ‘Check Engine’ light goes on, the computer is trying to tell you what the problem is. You need to get the code read. I doubt that it is an ODB-II car, but you may be lucky. Some European models had ODB-II as far back as 1994. Get the code read and let us know what the computer sees as the problem.

As a rough guess, I’m leaning towards a compressor problem, like getting close to locking up. If it does lock up, it will fry the drive belt. If anything else is also run by this belt, it will stop turning, as well.

UPDATE
AC is dead (compressor not engaging) car doesn’t accelerate properly, doesn’t achieve normal operating temperature, check engine on. really hard to find an OBD I without hundreds of dollars. any ideas?

Check the ground straps, and that the battery voltage stays 13.5-14.5V when accessories are turned on.