#OxygenSensor

Joey writes:

Hello Sajeev,

I’ve been a reader of yours for years and greatly enjoy your style. (Woot! —SM)

My question is about my ’97 Mazda 626, with a hair over 215,000 miles on it, that’s been in my family for its entire life. It’s reliable, economical, and generally in good condition.

However, I am up for a registration renewal in October, and I need to complete an emissions test. I figured that it would be a good idea to check up on the codes behind the check engine light. The codes came up as an evaporative system and catalytic converter errors, which are both emissions fails.

TTAC Commentator Dave M writes:

Hey Sajeev!

A question for you and B/B. Especially during cold weather my Trooper gets a ’clunk’ shifting from 1-2 (it’s a 4 speed automatic) and then back down. This coincides with a CEL. It doesn’t happen all the time. There are other times (even during cold) where the truck runs normally – no clunk, no CEL. Checking the CEL code and it indicates all four oxygen sensors (replaced last year); when no CEL no code to read.

My first thoughts were it might be time for ANOTHER transmission. But my brother says no, it has to be electrical since it’s intermittent. Any ideas where to start?

TTAC reader sportsuburbanGT writes:

Hi Sajeev,

Have a couple of questions: I have a 72 Dodge Dart that I am performing a 318 to 340 swap. It’s taken longer than I planned (lack of time), I backed the car in the garage 2 years ago and now I am planning on firing it up in this April. The question is the gas: I had about a half tank when I backed it in, and I put some Stabil in the tank, but I took the cap off to try a new cap and the tank smelled really awful. I replaced the fuel filter, but should I drain the tank and refill with fresh gas, put some fresh gas in the tank to mix up what is in there, or pull the tank have it boiled out and refill. I was driving the car up until March 2009, and I put that last half tank in there in March 2009. I am in Long Island, NY so we have that crap gas till April.