1990 Ford F-150 Repair Question
Topics covered: Check engine light, Engine, Sensor.
Mileage: 180 miles.
Mileage: 180 miles.
Asked on May 5, 2012
How do I get it to idle smooth and pass smog?
4.9l 5speed 4X4 duel tanks did tune up and replaced fuel pressure regulator.Still is idleing too rich and has a missfire at idle.
Asked by FreAkytOasTer777Answer
Replied on May 5, 2012
look for vacuum leaks. is the check engine light on?? o2 sensors were common back in the day. map sensors were issues as well. all need to be verified by a shop with a scan tool.
Roy
Replied on May 5, 2012
check engine light is on steady, i checked seld diagnostic and codes "31" and "67" are flashed Would the evp voltage being low (code 31) make it do that?
Replied on May 5, 2012
not really unless it is pulling raw fuel from the tank but not likely. you need some help here unless you have a scan tool
Roy