Greetings All,

I've been to this forum before and found it very helpful. I've searced for a while on the issue I'm having and although there are topics the touch on it, I'm unable to find anything with my particulars. So.....here goes and thanks in advance!

My check engine light has been on for a week or so and I finally took it to AutoZone. They hooked up the reader and it informed me that the car is running lean (1st bank?) and that my catalytic converter is clogged. The light went out after AutoZone so perhaps the reader reset it? What I'm wondering is whether or not the findings of the reader are likely to be accurate? Should I have the converter replaced based on what the reader found?

Here's a little background: I've recently noticed my gas mileage decreasing (going by the on board display on the ceiling and more frequent trips to the gas station). The catalytic converter under the car rattles, and has rattled for some time.

The Car: 2000 Blazer, 4Dr, 2WD, 145K miles.

Any help will be greatly appreciated.

KCBlues (A.K.A. Mike)

 

What were the codes (Pxxxx) that were displayed on the code reader? With those, we can walk through the diagnosis.

 

Well, I finally got the P codes....

P0171 & P0420

NOTE: P0420 came up twice on the code reader, not sure if that's significant.

Thanks again.

 

Probably just that it is both current and stored.

P0171 - Fuel Trim System Lean Bank 1

P0420 - Catalyst System Efficiency Below Threshold (Bank 1)

I would be looking for an exhaust leak on the driver side between the head and the O2 sensor.