Chevrolet Malibu Code P0171, P0455, P0420

2004 Chevrolet Malibu 2.2L Ecotec P0171.
Question = Can the Mass Air Flow sensor be tested with a multi-meter? Why does my malibu have this code.

It can be done if you have a meter that can reads hertz. Best way is to look at data on a scanner after checking the basics- power, ground, continuity of wires. A common cause for this condition is a vacuum leak. There is also a PCM update available to correct a false setting of this code.

2005 Chevy Malibu. Engine size = 6.0.
Question = I have 2005 malibu that has a sucking like vacuum noise coming from engine and it has no power when taking off because it is sucking in so much air.

Answer: By your description, this would be hard to determine without actually hearing - feeling the car. But you should have the fuel pressure checked, make sure all the air intake system is intact between the air filter and the engine, and have the catalytic converter checked for being plugged.

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I have a 04 Chevy Malibu and my check engine light is on. I have a friend who has a scanner check it out and it read code p0455. She doesn't know what the codes mean and we looked online to find evap leak.. Our problem is that we dont know what that is, can u help??

A trouble code P0455 is for the Evaporative Emission System, and it means there is a large leak detected. Basically, the EVAP system controls fuel fumes and monitors fuel tank pressure. When the system cannot seal properly, it will set a code. The code you have is for a major leak, and by leak I mean a leak of vacuum from the system or fuel vapor escaping when it shouldn't. The most likely cause is a gas cap that wasn't properly put back on, or the car being fueled while it was running. Check to make sure the gas cap is tight and the proper type for your car. Another possibility is what's called the EVAP Vent Solenoid. If there is a problem with that solenoid, it will let the fuel vapor vent to the atmosphere when it should be closed. It will most likely have to be checked out by a professional. They can put a better scanner on the car to check for problems and can also pressurize the EVAP system to find a leak easier.

hello. My malibu has a check engine light on sometimes. I took it to auto zone and the code came back as p0171. They said that is lean and i need a new oxygen sensor. Can you tell me if this is right, and how do i replace an oxygen sensor. Thanks. 2005 Chevy Malibu. Engine size = 2.2L ecotec.

The conditions you are describing relates to a service bulletin ( TSB ) for a lean condition on this vehicle. You are still under factory warranty, and just need to take to the chevy dealer. What they will do is re-program your pcm (powertrain control module). This procedure should take about 1/2 hour.

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2001 Chevy Malibu will act like its starving for fuel and lose power may go 25 and may not go at all. Never really dies out that much sometimes will start right back but usually have to leave sit a couple minutes and then it may be fine for a couple days. Short distances the CEL was on for EGR valve which i replaced to no avail. Car has strong fuel pressure at the rail when it wont start.

I thought fuel strainer car will throw no codes except low catalyst P0420 after egr replaced. I dont know what to do with it its stalling out on me and its dangerous because it wont move when it does it and it hisses like out of the MAF? Sometimes i will have to let the car sit but sometimes just for a minute or 2 and it seems to run ok again. It acts like it is fuel because if you get on it hard it will sputter but at like 4500 RPM and up but at times not do that.

You may have more than one thing going on with your car.
The code for the Catalyst efficiency low P0420, along with the problem of no power or acceleration, indicates the Catalytic Converter is plugged. This is very common for this condition, as well as the code for the EGR.

But, this usually will not cause the car to stall, and would not cause it to be hard to re-start. That may be another issue. You may have an ignition module going bad, a crank sensor problem, faulty ignition switch, a ground wire problem, or other problem. I would get the converter checked out first.

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