Engine - Poor Hot Start/Rough Idle
84amcjeep01OCTOBER 1984 000 319
1984 AMC/JEEP MODELS
22E
ENGINES Attention: Workshop, Parts Department
ENGINE PERFORMANCE DIAGNOSIS
Information
On some 1984 AMC/Jeep models with a 2.46 liter I-4 or 4.2 liter I-6 engine, difficult hot starting and/or a rough idle may be caused by the fuel return check valve.
Verify the fuel return check valve operation as follows.
FUEL TANK RETURN HOSE AND FILTER LOCATIONS:
FUEL TANK RETURN VALVE ASSEMBLY:
Procedure
1. Remove the fuel tank return hose A (see illustration).
2. Inspect the location and position of the fuel return check valve B (see illustration). The check valve should be in the end of the return hose A that is farthest from the fuel filter C. The small diameter end of the valve B should be toward the filter C as shown. If the valve is incorrectly installed, proceed to step 3. If the valve is correctly installed but an idle or hard start problem was experienced, install the hose and perform further diagnosis.
3. Remove the check valve from the hose. Verify the valve operation by blowing air through each end of the valve. Air should pass in only one direction through the valve; into the small end and out the large end.
4. Insert the valve into the lower end of the return hose. Push the valve into the hose until it is
approximately 28 mm (1.1 ins.) from the end of the hose. Be sure that the small diameter end of the valve faces up and toward the fuel filter.
5. Reinstall the assembled return hose and check valve. Lubricate the hose I.D. with RuGlyde or a similar product if the hose is difficult to install on the fuel lines.
S.R.T. Information
OPERATION DESCRIPTION NUMBER TIME TIC
CO. VALVE, FUEL RETURN CHECK -
INSPECT 1999 0.2 1-343
SO. FUEL RETURN CHECK VALVE - R&R
(Inc. reposition valve and install hose) 1999 0.3
Filing Instructions
Record this I.S. Note on page B-228 of the M.R. 244, page B-12 of the M.R. 251 and M.R. 252 and page B-13 of the M.R. 253 and file it in your M.R. 171 binder.