A high reading could be the result of a spread or damaged Under Valve Cover harness or damaged valve cover gasket re-check any high readings at the glow plug itself. Resistance should be 0.1-6 ohms depending on engine temp. The glow plug terminals are the outer two on 94-97, outer four on 98.5/99. If the relay tests fine test the glow plug resistance to ground at the valve cover connectors. On 97 and newer vehicles inspect the bank circuit divider shunt for damage. If there is no voltage out of the relay, check for voltage in at the main terminal as well as key power and PCM-controlled ground at the two-wire connector.
Most recent part number is F7TZ-12B533-CA and can be identified by a gold-colored base. There is a history of burned and melted relay terminals and a couple of updated relays. The voltage should be greater than 10 volts during the glow plug cycle. Turn the key to the run position and check for any voltage drop at the outlet side of the glow plug relay. This will cause the PCM to energize the glow plug relay for 2 minutes, and set a code. This usually indicates a problem with the glow plug system.ĭisconnect the Engine Oil Temp (EOT) sensor at the rear of the oil reservoir. Oil leakage from cylinder head passage end plugs, 94-99 Intermittent Computer Reset, 95-01 F- and E-Series Intermittent light knock at idle or low speeds-98.5/99 99.5/00ĩ9 F-series loss of power or stall in 0° tempsĩ7-99 E-vans with modified electrical systems-Hard start/Long crankĩ9 F-Series without cruise control, idles too low coldĩ9.5/2000 High Injection Control Pressure Readingsĩ8/99 E-Van 99 F-Series built through 4-12-99, Check engine light/DTC P1298 Hard start when cold, "Check Engine" light comes after starting, 97 and up California emissions
Stall when engaging reverse or manual first gear-auto transĩ9 F-series lack of power, rough idle, "Check Engine" light on, sucking sound on acceleration Rough idle-manual transmission "Bearings in a can" rattle noiseĩ6/97 stalling after a long decel/down grade Loss of power after hard accel rough idle, "Check Engine" light on, DTC P1211 Lack of acceleration when cold, limited RPM, hissing noise under hood, DTC P0470-478 No throttle response, engine only idles, DTC P0220 or P0221 Vehicle bucks and jerks in parking lots, especially w/ manual transmission Hard start, irratic idle and/or loss of power, DTC P1298-All models In wet weather-95-96 E-van No start at times Intermittent stall when driving Power "hitch" at cruise or under load DTC's P0340, P0341, P0344 No/hard start hot or after stall, restarts after cooling Jerky, irratic idle DTC's P1211, P1212, P1283
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