Engine Performance problem
2004 Ford F150 V8 Four Wheel Drive Automatic
Vehicle is rough on first startup for the day. Upon acceleration a puff of black smoke is visible from exhaust. No code shown when hooked to diagnostic computer
Thursday, July 2nd, 2009 AT 7:18 PM
1 Reply
RASMATAZ
MECHANIC
75,992 POSTS
Running rich:
Possible causes include a bad O2 sensor, excessive fuel pressure (bad fuel pressure regulator or plugged return line), leaky fuel injectors, dirty air filter or restricted air inlet, or a defective coolant sensor that prevents the engine management system from going into closed loop mode.