Uneasy Over Engine Heat

2 months ago, I bought a 1996 Proton Wira 1.6 XLi (auto). Whenever I drive long distance, I can feel heat from the A/C vents. The temperature gauge needle always point at the middle section its reading. I pop open the hood and I can feel the tremendous heat from the engine. What is the problem?

The odometer is giving me problem too. Before I started from Kuala Terengganu to Kelantan, the meter showed 11,824km. When I reached Kelantan, it indicated only 11,846 a difference of 22km. Has my odometer cable gone bonkers or is some glass particles causing this? I found some glass bits twice under the floor mats and under the seat. I have feeling that the car was involved in an accident before. A mechanic showed me an old cross member and some sign of serious damage on the bodywork.

Reply:
I do not think you are having an overheating problem because if so, your engine would have 'cooked' by now. When you mention hot air coming out of the A/C vents, is it all hot air, or is the air cold a bit, but you can feel occasional heat? If you feel only hot air, then your A/C thermostat maybe faulty or the expansion valve is freezing up and that can be sorted out by any god A/C technician.

On the other hand, if you sometimes feel hot air coming out of the vents, then you need to check if there is heat from the engine compartment coming into the air conditioning system. For that you would need to go under the dashboard to look for open vents or loose hoses. By the way, it is normal to feel the heat on opening the hood after a long run and does not necessarily mean that there is any problem with the engine.

Regarding the odometer, it could be the cable or the instrument itself. Try unscrewing the cable at the instrument and gearbox ends and replace it, making sure that the cable seats correctly. When the cable disconnected, try running the inner cable and check if it is sticking. If so, replace it. If after replacing the cable, the problem still occurs, swap another speedometer. I do not think the problem is with the cable because if the cable is faulty the speedometer needle would be moving erractically and you would have mentioned that