P098

PCM Circuit:

DESCRIPTION
This diagnostic test monitors idle speed and gear selection from Park or Neutral to Drive or Reverse when the throttle is in Idle Speed Control (ISC) speed range. If idle speed is greater than desired, the Powertrain Control Module (PCM) will retard the spark to reduce engine power and set Code P098.

DIAGNOSTIC CIRCUIT CHECK
^ The primary purpose of this code is to detect an action of the driver that could cause a harsh shift from park or neutral to drive or reverse.
^ This code can be driver induced by shifting into gear at a throttle angle of less than 20° with the throttle depressed.
^ Check for code P030 as a slow or inoperative ISC motor may cause the code to set.

TEST CONDITIONS
Codes P021 and P022 not set.

FAILURE CONDITIONS
1. Engine running for 5 seconds.
2. Gear selector moved from Park or Neutral to Drive or Reverse.
3. Engine rpm 600 greater than engine speed determined by the PCM (if Code P098 is already stored in history, use an RPM of 200 greater than determined byte PCM).
4. A throttle angle less than 20 degrees.
5. Vehicle speed less than 6 mph.
6. P/N to D/R fuel shut off not enabled.

ACTION TAKEN
PCM retards ignition timing.