Test NTC-19A - Checking Engine Mechanical Systems
NOTE:
If coming to this test from an oxygen sensor test and rich or lean condition is not corrected after checking items listed below, replace Powertrain Control Module (PCM).
At this point in diagnostic test procedure, all engine control systems have been determined to be operating as designed and not causing a driveability problem. Following additional items should be checked as possible causes:
- Check if any Technical Service Bulletins (TSBs) apply to vehicle.
- Check engine vacuum. It must be at least 13 in. Hg in Neutral.
- Check valve timing.
- Check engine compression.
- Check camshaft lobes for abnormal wear.
- Check crankshaft sensor slots for debris or deterioration.
- Check for exhaust system restriction.
- Ensure PCV system is functioning properly.
- Check camshaft and crankshaft sprockets.
- Check torque converter stall speed.
- Check power brake booster for internal vacuum leak.
- Check for fuel contamination.
- Ensure injector control wire is connected to correct fuel injector and injector is not plugged or restricted.