Service manual

G424F(FE) Service Manual 238 Chapter 8. Basic Troubleshooting
Lack of Power, Slow to Respond / Poor High Speed Performance / Hesitation During
Acceleration (cont’d.)
PROBABLE CAUSE CORRECTIVE ACTION
Component malfunction
Check SECM grounds for cleanliness and secure
connection. See SECM wiring diagrams.
Check alternator output voltage. Repair if less than 9
volts or more than 16 volts.
Check for clogged air filter and clean or replace as
required.
Check exhaust system for possible restriction.
Refer to Chart T-1 on later pages.
Inspect exhaust system for damaged or collapsed
pipes.
• Inspect muffler for heat distress or possible internal
failure.
• Check for possible plugged catalytic converter by
comparing exhaust system backpressure on each
side at engine. Check backpressure by removing
Pre-catalyst O2 sensor and measuring
backpressure with a gauge.
Engine mechanical
See Chapter 3 Engine Mechanical System.
Check engine valve timing and compression
Check engine for correct or worn camshaft.
Related MIL Faults:
EST faults
ETC faults
ETC spring check
TPS faults
APP faults
Encoder error
Delayed Shutdown faults