I've got a 1990 GTU with 58k miles. I've got two minor problems that I need help with. First, the sunroof retracts very slowly and needs a "push" to open fully.
Second, this car is almost impossibel to start in winter at temperatures below 30 degrees. Any and all help will be appreciated.

 

Not sure about your starting problem (maybe cold start system is messed up) but it sounds like your sunroof might just need it's tracks cleaned and regreased....I know mine does...I sure am lazy.

 

FIxing the sunroof is easy, just clean and lubricate the tracks. Use a good lithuim based type grease. As far as the cold start, I am not going to be able to help you.

Rat

 

Problem A: Sunroof operates slowly and needs a nudge to open/close fully:

Solution: Degrease the outer tracks, clean them, and replace the lining (which is sticking and causing the problem)

Problem B: Hard to start in cold weather

Probable Causes: Insufficient compression, Faulty OMP, Faulty Fuel System, Faulty Electrical System.

Solution: I'd go with "Faulty Electrical System". This is very easy to diagnose. Check battery, check wires, check plugs. If you can replace them all (if they need replacing ). Check alternator. Check starter. The FSM has a couple of easy tests for each and every one of these components. You should be able to diagnose/fix within 30 minutes.

 

cold start issues can also be related to improper oil viscosity.

If you really are seeing below 30 F, make sure you are using 10W30, or if you are seeing temps under 0 F use 5W30.