Took my 1996 XJS 4.0 Conv. out for a ride today. It was nice sunny day in NC and I turned the heater off but it was still blowing hot air. After about 30 miles it seemed like the console area was getting hot. In fact it was so hot that the ashtrays were almost to hot to touch. Temp. gauge was normal and it was running fine. I've only had the car for a few months but haven't noticed this before. Any ideas?

 

My first guess is that one of the two heater hoses that feeds the vents in the back came loose or has a hole in it. On the coupe there is a heater hose on either side of the transmission tunnel that runs from the unit in front to feed vents for the back.

Not sure if you have a back seat, though, so that might not be possible. Also not sure if that would make the ashtrays too hot to touch, but a heater can put out mighty warm air.

The transmission is also a possibility. It'll get up into the mid to upper 100s (F) when it is warm... the newer ones usually run around 175ish. It is RIGHT THERE under the ski slope, could be it.

Unless you've checked it, don't take the built in temp gauge as gospel. It is probably "close enough" but may be completely off. Worth checking - I use an infrared thermometer every so often to check for hot spots - worth doing since there are two thermostats that can fail even if the gauge is right.

I'm leaning towards escaping hot air from the heater somewhere, myself, even if you don't have the rear vents. They'd have had to cap the openings off which would probably be more prone to falling apart than the hoses. Someone will know more about the convertible.

 

Thanks - I'll pull it apart and check the hoses. I'm hoping it's not the trans overheating.