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Q: Catalytic converter now won't start

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I have a Pontiac 2004 grand am. One day the catlitic converter was glowing red hot, so someone from auto zone said it was clogged to cut it off, my husband done that and put a straight pipe and some clamps on it. After that i test drove it and it seemed like it took a while for it to start picking up speed, blue smoke was coming from the tail pipe. I drive it to my dads scared to drive it any further afraid I was going to mess it up worse. I asked around and tried to get people to check it out and they all said they couldn't find a reason that it was doing that. I went to start the car one day and it wouldn't start, or make any sound like it was trying to start. I need help I'm 8 months pregnant and really need my vehicale fixed. Thanks so much for your time.

My car has 153000 miles.
My car has an automatic transmission.

Hi there. The fact that the catalytic converter was glowing red hot does not mean it was bad. Removing the converter completely can sometimes cause more issues with the car, as it effects the sensor readings. The fact that the vehicle is running the way that you described and that the converter was glowing red tells me that the car was either running lean or rich. Most of the time this is a lean condition, which means too little fuel is being delivered to the engine. This is usually caused by a weak fuel pump.

In a case like this, I first check the computer for codes and check the fuel trim readings. I then check the fuel pressure. If that is fine then it may be a sensor problem. If you would like to have this looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose why your vehicle isn’t starting.

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