[joeylead]

When I first start my truck, the exhaust has a strong gas smell to it. When I last inspected it, they said it almost failed the emissions test. It is a 99 V6 with 127k and original ehxaust and o2 sensors. Is this a sign of the cat going bad or the o2 sensors going bad? The truck runs fine, and well, my mileage sucks because of the 35's. Any help would be great, I dont want to fail my next emissions test.

 

[ShowStop]

When I first start my truck, the exhaust has a strong gas smell to it. When I last inspected it, they said it almost failed the emissions test. It is a 99 V6 with 127k and original ehxaust and o2 sensors. Is this a sign of the cat going bad or the o2 sensors going bad? The truck runs fine, and well, my mileage sucks because of the 35's. Any help would be great, I dont want to fail my next emissions test.

The gas smell would be a clear indicator that you are running rich. If you are running rich, the extra unburnt fuel will shorten the life of the cat and burn it up. Mine does the same thing. I'll probably just replace the cat in 2 years when I have to get tested again. Provided my truck lasts that long....

 

[tanKoma]

check o2 sensor no1 can cause your engine fuel/air ratio to be out of whack

 

[joeylead]

check o2 sensor no1 can cause your engine fuel/air ratio to be out of whack

How do i check it? Should I pull it out and see if it looks damaged or are there better ways to do this?