Jaguar Repair: fuel tonk vaccum, vent hoses, vent line

Question
mi mr howard on my 86 xj6 when i open my gas pap before there was a suckson nois i dont kno// what happen but it/s not there anymore can u// tell me what may be the problem and also when i turn ma ac. on it take a long time before it diside to come on the compresser is running vents dont open. thanks and take care. ///james///

Answer
Hi James,
The tanks are under pressure not vacuum and it is about 3PSI. The pressure is controlled by a small plastic regulator valve in the vent line just behind the right front head light.

First look at the condition of the two gas cap seals (available from Jaguar) then if they are ok check the function of the valve. If you have a strong smell of gas in the car, start tracing the vent hoses under the rear window tray.

As for the AC/Heat system it is a complex system and the diagnostic procedure is long and can not be done via e-mail so you need to purchase a AC/Heat system manual from Jaguar.

The only simple things you can do is to check the freon pressures and check to see that there are two vacuum hoses connected to the firewall low on the right side.

Howard