Chart A-5 TPS Enrichment Check

Fig. 008 - Wiring Diagram for Chart A-5 TPS Enrichment Check. VIN C:

Wiring Diagram

Fig. 007 - Chart A-5 TPS Enrichment Check.:

TPS ENRICHMENT CHECK

1. This steps checks that the TPS will cause an ECM "Rich" command when fully depressed manually. On some cars, this will cause a low dwell (full rich) on others it will not.
Code 21 should normally be set.
2. This step distinguishes between a faulty TPS or ECM harness/ECM.
Code 21 should normally be set provided engine RPM is not set above specifications.
3. This step checks for 5 volt reference at TPS. It should be about 5 volts.
4. This step checks for a grounded circuit. Normal circuit should read about 5 volts. Checking for grounded TPS output to Terminal "5" of ECM or short in wiring to Terminals "5" and "8" from TPS indicates whether fault is in wiring or ECM. A voltmeter with a 10 megohms resistance must be used for an accurate reading.