Buick Repair Questions? Ask a Mechanic for Answers ASAP
Is the check engine light on?
is engine hard to start after refueling?
Warm the engine up to where you would normally have a problem starting the engine. Unplug the mass airflow sensor and try starting the engine. Does the engine stay runnning on its own?
Try repeating just to be sure. If the same thing occurs, replace the mass airflow sensor.
This is a common issue. Check for breakage in the wires going to the front abs wheel speed sensors. The wires flex each time the suspension moves or the wheels are turned. Eventually these wires break inside the insulation giving an intermittent fault. Front wheel speed sensor harnesses are available from most auto parts stores.
If the harnesses are okay then you may have a sensor dropping out at low speeds. If this is the case then the front wheel bearing (hub) would need to be replaced.
Did you already replace the mass airflow sensor?
Was the P0172 code present before replacing the mass airflow sensor as well?
Pull the vacuum line from the fuel pressure regulator (on fuel injector rail) Check for fuel in the vacuum line or in the port on the regulator. If fuel is present there, replace the fuel pressure regulator.
If air filter is clean and fuel pressure regulator is not leaking and problem was present with the old mass airflow sensor then looks like you may have a leaking injector. Try running some injector cleaner in the gas tank and see if this makes a difference. Add a whole can to 1/4 tank of fuel ( so the cleaner does not get too diluted ) and run it through the engine for a few days to see if this makes a difference.