AskPatty Certified Female Friendly Logo

Hi, I recently purchased a gently used 2006 Chevy Cobalt. I noticed when the fuel was low, around 1/8th or under, the rpms would get erratic. The problem was intermittent and went away once I fueled up. Yesterday, however, I let the tank get low again and the problem got pretty severe with a yellow check engine light coming on. I managed to get home and find parking (city street on an incline with nose up) at which point I shut the engine. Now the engine cranks and runs but shuts down almost instantly. What could be the problem? Would adding more fuel be the next step? After I parked and tried restarting I got a low fuel warning on the dash. Thanks for any help! -Harry

Answers from the Automotive Experts

Jessica Howe, Automotive Expert & Coach at


Thank you for writing in. A fuel pump that is starting to fail may become erratic when the tank is running low. The fuel filter may be clogged and in need of changing as well. The only way to tell is to have the fuel pressure tested at the engine when the fuel levels are low. Further testing and repairs can be decided upon at that point. Good luck!

LeeAnn Shattuck, Chief Car Chick at The Car Chick

It sounds like your fuel pump is failing.  The fuel pump sits at the bottom of your car's gas tank and pumps the gas from the bottom the gas tank into the engine.  The gas also works to keep the fuel pump lubricated and cool.  When you drive with low gas (less than 1/4 tank), there is not enough gas to lubricate and cool the fuel pump.  This causes excessive wear and tear on the fuel pump, causing it to burn out.  You should always try to keep your gas tank at least 1/4 full to avoid damaging the fuel pump.  Keeping your tank more full may extend the life of this fuel pump, but the damage may already be "fatal", and you will need to have the fuel pump replaced.  

Contribute to this question:

blog comments powered by Disqus

Related Chevrolet Cobalt FAQs

  • My check engine light is on solid but the car runs fine gas cap is tight why is it ... Read More

  • Yes my mom's 2007 acted up today. She got a check engine light on and a power ... Read More

Need Car Advice?

Ask The Experts!

Looking for a New or Used Car?

Search for our Certified Female Friendly® Car Buying Marketplace locations

Help Our Charities