Chevrolet Impala Emissions Leak And Brake Noise

Just had spark plugs, plug wires, thermostat, fan assembly and head gaskets replaced on my 2002 Chevy Impala . The check engine light came on and on and Autozone gave a readout of an air leak. He said it was probably something with the gas cap or fuel line. Please what else could it be?

Answer: Well, there really is no code for “Air Leak”. By him telling you that you may need a gas cap, it leads me to believe that you have a code for the evap emissions system. This is sometimes how people get a description of that system. Without the actual code number, I would just be able to take a guess. It may be check engine light code P0455 – large evaporative emissions system leak. Yes, this could just be a bad or loose gas cap. The problem on your Chevy Impala could also be that during the repairs that were made, the mechanic left something off or loose.

There is a common problem for this code though. It is what is called the Evap Vent Valve. This part is normally the cause of a code P0455 large leak. This is located above and behind the drivers side rear wheel. The proper way to diagnose this problem is to have a mechanics do a pressure test on the system to determine was is either not functioning or leaking. It would be leaking fuel vapor,  not gas. If the light and code was not there before these repairs, i would have the shop that did the work check to make sure they did not forget something first. Most shops will check their work for free for you, especially if it was at the Dealer.

2004 Chevrolet Impala Brake Noise

Hello i found a car on Craigslist that I would really like to purchase. It is a 2004 Chevrolet Impala with 113000 miles. The only problem with it is that when I went to test drive it I could here a loud thump whenever I used my brakes. It didn’t do it until I came to a complete stop. It sounded like it was coming from the trunk but I checked in there after and the trunk was empty. Any ideas what that noise could be?

The noise you are hearing could be a few different things. It could be brake related. Possibly a loose rear caliper, or warped rotor. Maybe even a loose or missing emergency brake component. The E-brake hardware is inside the rear rotor and would need a physical inspection by removing the wheel, brake caliper and rotor.

But, this could also be a suspension problem, since you say it only does it when you come to a complete stop. Normally brakes noises will occurr during all braking action. I would have the rear shocks checked, along with the stabilizer links and all other rear suspension parts to be safe.

If all these things check out good, then a thorough test drive with a technician would be needed. Drive it with him to point out the sound you are hearing. We are more than happy to drive with a customer in order to be sure we are hearing the same thing you so we can get your car fixed right the first time.