Need Help dont know what to do, engine not having power.

[ranjmaz]

My coil pack was replaced in January. A back flow test by mechanic showed excessive pressure and he thinks the cat is clogged, any idea where he would have taken this reading from? He said it took 10 mins and didn't charge me, should he have taken the reading from the 1st oxygen sensor hole, the 2nd oxygen sensor hole (the one after the cat), or is there a valve?

I'm going to try removing the 1st 02 sensor again (I still have the manifold off), keeping it plugged in, and seeing if the car accelerates differently/better. Right now, I can't get over 2500 rpms, and the top speed is 60 mph.

If it's the catalytic converter, since I have a 2008 with 43k miles, its replacement, parts and labor should all be covered under the Federal Emissions Warranty 80k/8 years: http://www.epa.gov/obd/pubs/420f09048.pdf.

I assume my mechanic couldn't do this work and it would have to be done my a certified GM tech?

[ranjmaz]

Update:

The backflow test was done from the 1st 02 Sensor Hole (before cat), as expected.

With the 1st 02 Sensor removed but hooked up, the car was understandably louder, but ran much better. In fact, if not for the noise, it was hard to tell anything was wrong. I was able to get 2nd gear well past 2500 rpm, upwards of 4k, and in 5th gear, I got past 60 mph, up to 70 mph with no issues.

The codes that resulted from this test were P0131 and P2187.

Thanks for that tip!

[petrified.rabbit]

its tough when no one replies, but congrats on what sound like you fixed your car.

[ranjmaz]

Thanks rabbit, I have a 1 PM appt at a local dealer. The tech looked up my VIN and confirmed that if it's the cat, diagnosis/labor/parts will be covered by the Emissions Warranty. I will follow up after that.

[Chevy Customer Svc]

Hello ranjmaz

Feel free to keep me posted on your dealer visit and how your Aveo is running. Also remember that if you have any questions or need any assistance to let me know by private message.

Jackie
Chevrolet Customer Care

[ranjmaz]

My car has been fixed free of charge under the Federal Emissions Warranty (8yrs/80k miles) and is running great. Many thanks to Petrified Rabbit, Jackie and the fine folks at Alma GMC, in Michigan. I am going to post a new thread under maintenance detailing my ordeal and this Warranty fix, which doesn't seem to be well known and perhaps should be.

Thanks,

RanjMaz