Fuel pump or oxygen sensors?

Jmason34 · Post by **Jmason34** » 22 Apr 2011, 20:10

I am having issues with my car starting since having the fuel pump replaced due to the recall. I have taken it back to the dealer on 4 occasions and they have told me that it was part of the adjustment process (x2) and then it was due to an oil leak (repaired) and then finally, oxygen sensors. Needless to say, I didn't believe any of these reasons. I explained this to my mechanic (whom I trust) and they explained that the O2 sensors *keep* your car running and were not needed to get it started. They suggested that I prime the line and the car should start; this method works every timehowever now, my car sounds like it is trying to stall out when I am stopped at a light or trying to accelerate which leads me to believe that it is O2 sensors (or worse??). Could this be related to the fuel pump issues or is there a much bigger problem?

Post by **kcodyjr** » 22 Apr 2011, 21:10

Adjustment process, due to a fuel pump? I smell bull. Well, not the bull himself exactly.

Has the fuel filter been changed recently?

Other reasons for stalling might include the air filter and fouled spark plugs, or a dirty/worn MAF sensor, but if it was driving fine before going in, they'd have to have screwed something up. Perhaps they pinched a fuel line during installation?

Certainly it does sound like it's starving for fuel. Have your trusted mechanic take a pressure gauge to the Schrader valve on the side of the fuel rail and check it against the book.

Jmason34 · Post by **Jmason34** » 23 Apr 2011, 06:19

Thank you for getting back to me...I am sure that the dealership is covering something up...I just can't prove it. Speaking of smell, when I drove it last, there was a "firework-like", smokey smell coming out. Any idea of what that might be?

Jmason34 · Post by **Jmason34** » 23 Apr 2011, 09:46

Advance Auto told me that I have codes P0455 and P0305 with a cylinder misfire in #4. How much can the cat converter take before it's damaged? Can any of this be caused by the fuel pump issues I've been having?

Post by **kcodyjr** » 23 Apr 2011, 13:58

Firework-like smell? Could be something spilled onto the exhaust manifold, or could be a rubber or cheap plastic piece being pinched against something hot like the exhaust manifold. Did you open the hood to look for the smoke?

Jmason34 · Post by **Jmason34** » 23 Apr 2011, 15:13

The smell is coming from the exhaust pipe and the car runs and idles rough. There's definitely a strong sulfur smell coming from the exhaust pipe. Everything I've read indicates that it's O2 sensors and cylinder misfire. What damage am I doing by driving it?

Post by **hansenjg** » 26 Apr 2011, 06:45

I doubt your O2 sensor is causing a misfire. Might be fuel injector in #4 is plugged. Could also be that you have a bad coil on #4. I had a sudden catostrophic failure of a coil that gave me that code. Replaced the coil and fixed the problem.