HC problems

[boosted231]

I was hoping someone could give me a suggestion on HC. The car is an 89 tta all stock except a 160 degree stat and ATR pitbull cat back system. The car has a fresh tuneup and fluid changes. The car smells like it is running a little rich. Would the 160 stat keep the motor too cool for the cat to work properly? If someone could point me in the right direction I would appreciate it. Thanks

 

[gofstbuick]

What kind of chip, is it burned for the 160 degree t-stat? Rich will be the smell of sulfur (or a rotten eggs smell). The few things that would degrade a cat are misfires, coolant and /or the use of non O2 sensor safe sealants. If you suspect a HC problem, what are the rest of the readings? HC is unburned fuel, and if that is true, I would look towards ignition issues first. If you feel it is rich, then I would gear my diagnosis towards fueling, or A/F mixture issues. Rich usually centers around CO emisions.

 

[boosted231]

It has the stock chip in it. I pulled one of the plugs and it looked brand new. I'm not sure of the other readings but they were fine as far as emissions.

 

[Dan Thompson]

Is there an exhaust leak before the O2 sensor, like a cracked header or a leak in the crossover.

 

[boosted231]

No exhaust leak that I can hear. This car only has 49,000 miles on it. Very clean and stock car.

 

[gofstbuick]

Originally posted by boosted231
It has the stock chip in it. I pulled one of the plugs and it looked brand new. I'm not sure of the other readings but they were fine as far as emissions.

They may look fine, but that doesn't mean it is not running lean. All the emissions gasses work as a relationship that can be graphed. You claim that it may be rich, but richness relates to a CO issue (an odorless colorless gas). But in the title of the thread you claim that the engine has HC problems, issues related to possible misfire, lean condition, or possibly even mechanical engine problems. So, what is it? When I inquire about all the emissions readings, I'm trying to find out what's really happening. Tell you what, this is my email address:

joseph_cheung@dca.ca.gov


Send me an email address so I can email you a diagram of the relationship between emissions gasses and you'll better understand what I'm talking about. I would love to help you, but with the conflicting information, it's a really bad guess at that.

 

[boosted231]

I'll get the readings and email them to you. Thanks