1986 Jaguar Vanden Plas Gas tanks and EVAP charcoal caniste


Engine Performance problem
1986 Jaguar Vanden Plas 6 cyl Two Wheel Drive Automatic 138000 miles

When the car is driven for 5-10 minutes gas will bubble out of the right fuel tank door, and when the door is opened it will pour out about 1/4 of a gallon. On the way back from getting new tires, gas then started to pour out of the breather hose of the charcoal canister behind the front passenger wheel. The cars accelerator could not be pressed without the car dying. I shoved a plastic bag in the breather hose and taped it shut, this allowed me to drive the 5 miles home. I looked at the rubber retainer behind the fuel door and it has some cracks in it, so my questions are.

A. Is the gas coming out because of these cracks, and also the pressure from the left tank felt somewhere it could go and forces its way out the right gas tank door and then the breather hose because it couldnt get out fast enough? And will it stop if I replace the rubber forming a perfect seal again?

B. Is my charcoal canister now ruined since actual gas has been through and out of it?

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have the same problem?
Monday, May 25th, 2009 AT 1:15 PM

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The fuel evaporation system is designed to keep fuel and crankcase vapor from escaping into the atmosphere. The system consists of a fuel tank (2 on XJ6) with expansion space, vapor separator(s), pressure relief valve (XJ6 III), restrictors, charcoal canister, and connecting lines and hoses.
Fig. 1: Fuel Evaporation System (XJ6 III)


When the fuel tank vapor pressure exceeds a pre-set limit, the pressure relief valve opens and vapor flows into canister for storage. The pressure relief valve also allows air to enter the tank when vacuum exceeds a pre-set limit. The purge line restrictor limits maximum purge air flow rate.

Every 30,000 miles check all lines and hoses for damage, leaks, deterioration, and obstructions. Check fuel cap seal. At 50,000 miles, replace charcoal canister.

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Friday, November 27th, 2009 AT 7:08 AM

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