QuestionQUESTION: mr howafr hope u/ar doing well 85 xj6 runs fine on right gas tank when i switgh to left after a while it seems it is starving for gas i switch back to right no problem i have change tank switch it works fine nothing in tank change filther fuel filther in tank and inline filther also.what els do i look for no restrictoon in fuel line have change the switches in wheel opnin those on frame .
ANSWER: Hi Jammes,
You said you changed some parts but did you do any testing? Is there a free flow of fuel from the left tank hose in the trunk? Is there a strong return flow of fuel to the left tank when the left tank is selected? (Easy to test, just select the left tank and open the left filler cap and with a flashlight look at the returning fuel.)
The system is designed so that if any of the valves fail electrically, you can run off of the left tank because when the left tank is selected the trunk switching valve has no current and the wheel well return valve has no current. The switching valve is spring loaded to open the left tank and close the right tank. The left return valve is spring loaded to the open position. The right return valve is spring loaded to the closed position and when you select the right tank, you power the switching valve in the trunk to open the right tank and close the left tank. You power up and open the right return valve and power up to close the left return valve.
My experience with the system has shown me that when you loose fuel from the left tank, it usually has nothing to do with the return valves as if there was an electrical failure or a sticking valve the fuel will just transfer to the wrong tank. When you loose fuel supply, it has to be either the trunk switching valve or line from the tank or the pick-up in the tank. You should also confirm that the pump is running when the left tank is selected as a wiring problem could be cutting the pump off when the left tank is selected.
To test the pump circuit, remove the air filter can and turn the ignition switch to "ON" (not start) and select the LEFT tank and reach in the airflow meter and open the flap door with your finger and listen for the fuel flow (it is noisy under the hood) If you hear it running, the pump circuit is ok.
Howard
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QUESTION: umm now that i got my 85xj6 where ti dont cut off with left tank switch on ti started poring out gas on right side quarter panel lower front i pull off lower panel to see where leak was coming from a hose in ft quater panel in front of gas tank.so i stop that by turning left wheel valve around now it goes to canister ithink i have 2 rt hand valve so i switch where the arrow wouls point to cront of car on left side // rt side arrow point to tank. can wiers hook pu wrong on trunk valve. ineed help so help me please. thank for every thing i pray that god bless u... uhave help so manny and thats something u didnt have to do good lufk in fetuer.
AnswerJammes, I can't make out what you are saying. If you are talking about vent valves, they must point toward the front of the car to the charcoal canister behind the right front head light. They are pressure valves that maintain about 3 PSI in the tank but when the pressure exceeds 3 PSI they open to exhaust the vapors up to the front of the car to the canister.
If you are talking about fuel return valves (the one at the lower part of the rear wheel well) The one on the right must be a valve that is normally closed and opens electrically. The valve in the left bottom of the wheel well is normally open and closes electrically.
Howard
