It may be losing engine compression because of a blown gasket, or just simply needs a tune up (new spark plugs, wires, distributor cap).
1990 gmc p/u 5.7 wont idle showing code 12
it is on the throttle body. usually held in by two screws.
To adjust the idle on a 1992 Buick Regal GS, first locate the idle air control (IAC) valve, typically found on the throttle body. Start the engine and allow it to warm up to normal operating temperature. Then, adjust the idle speed by turning the IAC valve's adjustment screw while monitoring the engine's RPM; aim for the manufacturer's specified idle speed, usually around 600-800 RPM in gear. Always double-check your adjustment by letting the engine idle and ensuring it runs smoothly.
The sending unit is likely faulty
your truck wont idle correctly when its cold, because its cold...and nothing runs correctly when it's cold. your truck wont idle correctly when its cold, because its cold...and nothing runs correctly when it's cold.
Usually the spark plugs or the timing.
Try the idle air control motor
the idle solinoid may need changing, or its power source is not plugged in or working. If the solinoid is not powered the carby wont know where to idle, it will drive fine but wont idle when you pull up at lights ect.
The EPA mileage estimate for the 2012 Buick Regal is 19 mpg in the city, 31 mpg on the highway.
u dont set the idle the ecm does the setting througt the air idle conrtol. If it wont idle u need to replace the aic motor on the th0rottle body!
The A/C idle compensator solenoid is not functioning. This should be located next to the carb.
possibly a vacuum leak, low fuel pressure, or the idle air control has failed,