When driving brake and battery light comes on....car looses power goin uphill especially on a gradual incline...its as if im hitting my gas and thn hitting the brakes right after..while ths is happening the batt and brake light stays on instead of the usually flashing..alternator was replaced and tested, mechanic said it looks fine
I have a cat code bank 1 error so im thinking it could be a clogged cat but my mechanic reckins i need a new transmission...any ideas? Also if i remove the cat, can i drive with just a straight pipe without hindering the cars performance?

 

The battery and brake lights on means that the alternator is not charging. Many rebuilt alternators will fail in a short amount of time. Yours seems to be intermittent. There isn't any way to test for intermittent. The only thing you can do is have a voltmeter handy and when the lights are on, check the voltage. A good alternator will produce around 14.2 volts.

You can replace the catalytic converter with a straight pipe and it will not harm the car. You will not pass an emissions test if your state requires it.

A new transmission? Really? You need a new mechanic.