NOTE: Ensure increasing engine speed advances ignition timing.

Ensure transmission is in Neutral or Park. Set parking brake. Inspect crankshaft pulley timing mark and timing mark indicator on timing belt cover. Clean marks as required. Start engine and allow it to reach normal operating temperature. Turn all accessories off. Attach timing light to No. 1 spark plug wire. Ensure idle speed is correct. See ADJUSTMENTS article.
CAUTION: Driving vehicle with jumper wire installed in test connector will damage catalytic converter.
Using a fused jumper wire, connect terminals "D" (ground) and "E" (test switch) of test connector. See ADJUSTMENTS article. Aim timing light at timing cover timing marks. If ignition timing is not within specification, loosen distributor hold-down bolt and rotate distributor to obtain correct ignition timing. See IGNITION TIMING table in ADJUSTMENTS article. Tighten distributor hold-down bolt and recheck ignition timing. See ADJUSTMENTS article.
NOTE: With jumper wire installed, timing should be fixed. if timing varies, terminal "D" is not properly grounded.
Remove jumper wire from test connector. Ensure ignition timing advances with engine speed (RPM). If ignition timing does not advance, check CTP switch, test switch terminal circuit and PCM.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Timing Control Systems