Fuel System - Poor Hot Starting/Long Crank Time
310-01DATE
2/97
XK8
MODEL
1997 MY-ON
XK8 Range
VIN
001001-ON
Fuel Tank Pressure Control Valve - Check Operation
Issue:
When investigating a customer complaint of poor "hot start" on 1997 MY-ON XK8 Range vehicles, verify that the fuel tank pressure control valve (Rochester valve) is operating properly.
Action:
After verifying a customer complaint of poor "hot start" (extended cranking) on 1997 MY-ON XK8 Range vehicles, check the fuel tank pressure control valve as follows:
1. Raise vehicle on hoist.
2. Remove the left front wheel.
3. Remove the liner from the wheel well.
4. Disconnect the vacuum hose from the fuel tank pressure control valve.
5. Connect a vacuum tester to the pressure control valve fitting.
6. Apply a vacuum of 0.1 - 0.5 bar (2.94 - 14.7 in. Hg.) If this vacuum does not hold for 2-3 seconds, the valve is faulty.
7. Disconnect the vacuum tester from the control valve.
8. If the valve held vacuum, reconnect the vacuum hose and proceed to step 16.
9. If the valve is faulty, cut and remove the tie straps that secure the control valve to the mounting bracket. Remove the retaining clip and disconnect the vent hose of fuel tank from the valve.
10. Loosen the retaining clip and disconnect the hose of the carbon canister from the valve.
11. Remove the defective valve.
12. Check a new valve by applying a vacuum of 0.1 - 0.5 bar (2.94 - 14.7 in. Hg.) as instep 6.
13. Install the new valve after checking.
14. Reconnect the hose of the carbon canister to the valve.
15. Reconnect the vent hose of the fuel tank to the valve. Install a new tie strap.
16. Reconnect the vacuum hose.
17. Reinstall the wheel well fender liner.
18. Reinstall the left front wheel and lower the vehicle.
NOTE:
In cases where the tank pressure control valve has been verified as working properly, proceed with basic mechanical checks followed by PDU diagnosis.
Parts Information:
Warranty Information: