Timing Control Systems

NOTE: Ensure increasing engine speed advances ignition timing.

Ensure transmission is in Neutral or Park and parking brake is set. Inspect crankshaft pulley timing mark and timing mark indicator on timing belt cover. Clean marks as required. Start engine, and warm it to normal operating temperature. Turn engine off with ignition on for 5 seconds. Restart engine, run it at 2000 RPM for 5 minutes and then return it to idle. Ensure all accessories off. Attach timing light to No. 1 spark plug wire. Ensure idle speed is correct. See IDLE SPEED SPECIFICATIONS table in SPECIFICATIONS article in this section.
CAUTION: Driving with jumper wire installed in monitor connector will damage catalytic converter.
Remove protective cap from monitor connector located beside battery. Connect jumper wire between ground terminal "C" and test switch terminal "D". Aim timing light at crankshaft pulley and timing cover timing marks. If ignition timing is not within specification, loosen distributor hold-down flange bolts and rotate distributor to obtain correct ignition timing. Tighten distributor hold-down flange bolts, and recheck ignition timing. See IGNITION TIMING table in SPECIFICATIONS article in this section.
NOTE: With jumper wire installed, timing should be fixed. If timing varies, terminal "D" is not properly grounded.
Remove jumper wire from monitor connector. Ensure ignition timing advances with engine speed (RPM). If ignition timing does not advance, check TPS, monitor connector wiring circuit, engine start signal circuit and ECM.