Notes On Intermittents

WARNING: This page is about a different car, the 1988 Cadillac Seville and 1988 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.

If code EO21 is intermittent, manipulate related wiring and observe ECM parameter ED01. Check TPS connector for shorts to voltage.

Cycle TPS through its travel and tap on TPS with a pencil to test for intermittent TPS operation. If fault is induced, parameter will skip to high throttle angle. If wiring and connectors are okay, substitute a known good TPS sensor and retest.

Review snapshot data parameters stored with this code to verify failure. If failure is verified, check and repair intermittent wiring connection or sensor.

Fig 1: Schematic, Code EO21, Shorted TPS Circuit

Fig 2: Flow Chart (2 of 2), Code EO21, Shorted TPS Circuit

NOTE: If hard code EO21 is accompanied by hard code EO15, see DFI Chart A, "Multiple Codes Stored Hard".

Fig 3: Flow Chart Code EO21, Shorted TPS Circuit