1998 Other Ford Models cold goes to heat in rear when load o

SHOSHANNAH

MEMBER
1998 FORD

Air Conditioning problem
1998 Other Ford Models Two Wheel Drive Automatic 205000 miles

This is a 15 passenger Club Wagon with a V-10 engine. I couldn't find those options above. It has 205,000 miles on it and has been a great vehicle. The power train runs great. When the air conditioner is running, and we have a load on the engine either going uphill, passing, or merging onto the freeway, the air conditioning in front turns off and in the back it switches to HEAT! My mechanic has put in a new check valve near the top of the engine and has tested the system for leaks and found none. He wants to try placing a resevoir and check valve near the passenger floorboard by punching a hole in the floorboard then repairing it. I have $350. Into his efforst so far with no results and believe it could be an electrical problem rather than a check valve. Do you have any suggestions?

1 Reply

HMAC300

MECHANIC
48,601 POSTS

If the front turns off then i'd say it's an electrical problem the rear could be experieincing what is called freezing up. And it is a condition of charge and has had moisture enter the system. Usually to fix this you have to evacuate the system completely and install a new drier and recharge the system. BUT if the front one turns off completely then i'd say it' may be loosing ground causing this maybe when the engine is loaded it takes the ground away from the a/c system, but the rear still works, but the compressor quits, making the rear blow heat.