Skip the auto shop - Our mechanics make house calls

Q: My impala will start but it will not run.

asked by on

ive replaced the cylinder heads and radiator and installed a new thermostat. i also had to get another 2 wire for my ignition module. now my car starts but wont run. to get it to start i have to press the gas at a certain time to get it to fire up and after then when it does it starts to idle low and shut off. then after it warms up it sometimes starts and runs till i put it in gear and it shuts off. so far i have checked the mass air flow unplugged it still shut off. next i checked the intake air sensor i shook the wire and it shut off checked the voltage on it and its getting 5 volts. and ive checked and cleaned the idle control valve and still it shuts off

My car has 230000 miles.
My car has an automatic transmission.

A: Hey there: Anytime you remove cylinder hea...

Hey there:

Anytime you remove cylinder heads, intake manifold or disconnect the fuel system, it's important to clear any OBD-II error codes that may have been triggered either prior to the removal or after you started the vehicle.

The issue you're describing is commonly caused by a communication error from the ECM to the air fuel ratio sensor, O2 sensors, and the throttle body itself. The system will permit initial flow of fuel to start the engine and keep it running while the throttle is depressed.

This might sound simple, but download and clear any error codes with a digital scanner. If this doesn't solve the problems, contact one of our local ASE certified mechanics to diagnose your stalling issue by inspecting your Impala's fuel and ignition system.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Possible starter replacement, not sure.

If your truck won't start because of a faulty starter you will hear no sounds when turning your key or maybe just a click sound. All the lights and other electric functions of your vehicle should still perform properly. If...

Q: oil is leaking onto the MAP sensor...and is intermittently stalling

If you were told that the upper intake needs to be replaced then this may cause problems with the MAP sensor and the way the engine runs. A MAP sensor is very important to controlling the fuel strategy to the...

Q: Temperature gauge not reading correctly.

This vehicle has had many electrical issues with bad crimps in the wiring causing gauges to read erratic and when the computers see issues in the wiring it will turn on the light and put the gauge to the low...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...