Throttle Body
- Start engine. Warm to operating temperature (cooling fan comes on). Disconnect canister vacuum hose from top of throttle body. Connect vacuum gauge to throttle body.
- Check vacuum gauge when throttle is slightly opened from idle. Vacuum should be indicated on gauge. If gauge indicates no vacuum, check canister port for clogging. Clean with carburetor cleaner if necessary. Turn ignition off. Check for binding or sticking throttle linkage. Replace throttle body if excessive play exists in throttle shaft or if shaft is binding or sticking.
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