Hi all. I have a 1994 850 sedan non-turbo. She has 225k miles on her, but runs like a champ. I do have a few non-critical issues I'd like some advice on...

1. AC Compressor cycles on and off. Pressure seems good, around 60psi. I had to jump it to recharge because it would just not come on. Now it does work, but will cycle off after some random interval of time. I can hear what I think is the compressor clicking on and off. I've seen some people suggest a bad relay or pressure switch. Any ideas on a good way to test this?

2. Relatively loud ticking noise coming from the engine. It appears to be coming from the injectors (or thereabouts). It gets faster with increased rpms. At some point, it will simply cease, and then slowly get louder until its back the way it was. Sometime slightly revving the engine will temporarily quiet it. Its kinda annoying, but I'm more worried this could be indicative of a more serious problem.

Thanks in advance for any tips or ideas!

 

Your A/C pressure is a bit too high – I believe it should be around 35 or 40. If it’s going on and off, you may need to shim the clutch plate.

The clicking could be the valves. What weight oil are you running – and is it topped-off?

 

Thanks for the response.

My pressure is actually 25psi right now. When I filled it 2 months ago, it went from 15 to about 40. 60 was just a really bad guess. I'll look into shimming the clutch plate.

The oil I'm using now is Penzoil 10-40 high mileage. Fresh oil and filter every 3k miles. Oil is topped off properly. I do notice that I can feel whatever is causing the tapping when I touch the fuel rail, but not the engine block. Can this be the valves? If so, what's can I do about this?

Thanks again!