How to Advance the Ignition Timing in a 1991 Ford Explorer
- 1). Open the hood of the 1995 Explorer and locate the spout connector. It is in the front of the engine, above the timing chain housing. Remove the shorting bar directly below the connector to access the timing housing. Not all models have a spout connector -- if you don't find this component on your Explorer, continue on to the next.
- 2). Attach the timing light and tachometer as specified by the timing light manufacturer. Start the engine, put the transmission in drive and firmly engage the parking brake.
- 3). Use the timing light to confirm alignment of the timing marks on the housing and the crankshaft pulley. The timing marks are located on the upper left of the housing when the timing chain cover is removed. Observe the timing marks. If the marks do not line up, the PCM should be checked and replaced if necessary by a qualified service technician. If the PCM is not defective, the timing chain or the tension bar may need to be adjusted. Both the timing chain and tension bar can be repaired or replaced by the owner or any auto repair shop.
- 4). Shift the vehicle into "Park," release the parking brake and turn off the engine. Reinstall the shorting bar. Remove the timing light and the tachometer. Close the hood.
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