Service Procedure
FUEL TANK INSPECTION1. Lift the vehicle on a hoist.
2. Locate the canister behind the left rear wheel of the vehicle and disconnect the fuel vapor hose to fuel tank hose clamp.
3. Connect the Low Pressure EVAP Tester (KENT MOORE/SPX EVAP Tester P/N J-44680) to the disconnected fuel vapor hose.
NOTES:
^ Select correct size hose barb fitting for the tool based on the inner diameter of the hose and install the proper size of hose barb onto the low pressure tester using teflon tape (or equivalent) to insure a good seal.
^ Slide the hose clamp over the barb connector to prevent any leaks.
4. Using a Mityvac pump (Snap-On P/N YA4000 or equivalent), connect the pump to the one-way valve in the low pressure gauge and then pump the system until the low pressure gauge reads 20 inches H20.
NOTES:
^ 1 inch H20 = 0.036 psi
20 inches H20 = 0.72 psi
30 inches H20 = 1.08 psi
^ The low pressure gauge is a very sensitive tool. Do not exceed 30 inches H20 (1.08 psi) when pressurizing the system (pressurize slowly!) or the gauge will be damaged.
^ Never use shop air.
^ Never pressurize the low pressure gauge by itself.
^ Slowly pressurize system up to 20 inches H20. Use the bleeder valve to bleed off pressure if over 20 inches H20 and allow 30 seconds for the system to settle. The system will "settle" (drop 3-7 inches H20) over a short period of time to equalize pressure throughout the system. Repressurize the system with the Mityvac pump up to a pressure of 20 inches H20 after "settling" has stabilized. Monitor the gauge for two minutes.
5. Monitor the pressure gauge for two minutes.
A1. If the gauge remains steady or drops less than 2 inches H20 (0.072 psi) in two minutes, the fuel tank does not require replacement.
A2. Reconnect the disconnected canister-to-fuel tank hose.
A3. Continue at step 10.
B1. If the gauge drops more than 2 inches H20 (0.072 psi) in two minutes, a small leak is present.
B2. Continue at Step 6
6. Diagnose the fuel filler neck first for a small leak by performing all of the following:
A. Swapping fuel caps with a known good fuel cap and repeating Steps 4 and 5.
B. Remove the left rear wheel, pressurize the system to 20 inches H20 and squirt the filler neck pipe area with soapy water. If no leak is found, continue to Step 7.
C. If a leak is found in the filler cap/neck area, repair and continue at Step 9.
7. Remove the fuel tank from the vehicle and inspect the rollover valve and fuel line hoses for signs of leakage. If there are no signs of leakage, continue at Step 8.
8. Replace the fuel tank with P/N 31150-34Q70, which includes the pads. Attach the pads in the locations shown with 3M(TM) Super 77 Spray Adhesive (or equivalent).
9. Transfer the fuel shut-off valve, rollover valve, and heat shield to the new fuel tank.
10. After any necessary repairs have been made, reassemble the evaporative system and repeat Steps 4 and 5 to verify the repair.
AIR INTAKE SYSTEM HOSE REPLACEMENT
11. Remove the air filter and hose that connects the air filter to the 2-way valve and discard them.
12. Connect the straight end (without the grommet) of the supplied hose (P/N 31377-34Q70) to the 2-way valve and secure with a hose clamp.
Insert the other end of the hose into the left rear side member (frame rail) as shown. Plug the grommet into the hole in the side member. Tie the middle of the hose to the fuel vapor hoses with a tie strap (P/N 17993-19000 or equivalent).
NOTE:
The hose end inserted into the side member hole should face toward the rear of the vehicle.
FUEL TANK REPLACEMENT
When installing the new fuel tank, tighten the self-locking nuts until the end of each looped fuel tank mounting band touches the vehicle underbody or the gap between the band and the underbody surface is .35-.43" (9-11 mm) as shown on the illustration.
1997 SONATA; 1998 2.0L Federal Spec Only:
EVAPORATIVE EMISSION SYSTEM SCHEMATIC
CAMPAIGN CLAIM INFORMATION
NOTE:
Submit claims using the campaign claim screen.