Q: 03 Saab 9-5arc 3.0t backfiring and has no power to drive. CEL blinking. I can hear the backfire under the hood and the tail pipe

asked by on September 09, 2017

Just started backfiring and has no power at all when I hit the gas. The CEL is flashing as well. The catalytic converter has been removed and replaced with exhaust pipe. When I put it in drive from park it bogs down alot! I couldn't even get up my hill and had to pull it with my Chevy. I checked all hoses and lines. Still no change. I bought the car 2 days ago and it was fine! This happened out of nowhere when driving on a flat surface. I can hear the backfire from the engine and out the exhaust.

My car has 159000 miles.
My car has an automatic transmission.

Engine is misfiring Inspection $79.99 - $99.99 Get a Quote

Hi Steve. Thanks for taking the time to contact YourMechanic.com today. I think the root source of these issues is the catalytic converter to straight pipe conversion that was completed. Unless the previous owner reprogrammed the ECU (which is highly unlikely and very difficult to do actually), then eventually misfire issues like you are experiencing will occur. It’s also possible that O2 sensors, other fuel system components or ignition system components are causing this problem. I think the best bet is to have a professional mechanic come to your location to complete a misfiring inspection, so they can inspect the vehicle and determine what course of action is best.

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