Natural gas smell?

lately I smell natural gas/ propane smell in my truck when in 4wd. Super wierd. Any ideas? Also my engine light is on for catalytic effeciency

 

Well looks like your cats are bad.

 

Is that a symptom?

 

Yeah. Cat(s) are bad.

 

http://m.carsdirect.com/car-repair/diagnosing-a-faulty-catalytic-converter

Sounds like it!
Sucks I have 2 cats. I wonder if it's the last one before muffler

 

If one is bad the other probably isn't far behind... May as well replace both.

 

Bwahahaha!

 

Dang they are expensive! And I don't believe you can do a cat delete without it sounds stupid or sending codes

 

Anyone heard of this brand?

 

From the bit of reading I've done it seems aftermarket cats are hit and miss.

 

Natural gas smell sounds like transfer case is overheating.
Check the fluid level in your transfer case.
If it was your cats you would still smell it in 2WD.

 

hahahaha BAD KITTY!

 

@fouillard13 , check out this thread:
https://www.tacomaworld.com/threads/addressing-some-common-misnomers-of-the-p0420-code.396763/

You should find out why your car is producing this smell before spending money to replace them. It may have gone bad, but you need to find out why, probably from the engine running rich.

I read the information in that link, and it is bullshit. Your catalytic has NOTHING to do with influencing the way your engine performs. The ONLY purpose of the catalytic is to change the chemical makeup of the exhaust leaving the engine to contain less hazardous chemicals.

The way your engine performs will affect how well the catalytic does its job. This is the reason i wrote the above thread, so many people on here dont understand what the O2 sensors and catalytic converter do.

 

Quick question? Have you had a check engine light lit for a real long time? This is one of the main reason the CAT's go bad. If not then get bad cat idea out of your head. Bad catalytic converters smell more like a trash fire than natural gas.

Gear lube smells more like natural gas than a bad cat ever will. Look around to see if you have a leak on the front differential.

 

Good observation.

You think he might be running without any fluid?

 

I know its pretty easy to go to the 'net and ask a question, but sometimes you just have to get down and dirty to find the answer yourself.

OP, have you crawled under the truck? Let us know what you find. There is a lot of knowledge on this site, but we still require some help to help you.

 

I must strongly disagree. I had a car one time that had no power off idle and would lug down when trying to run down the highway. The cat was clogged so bad that the exhaust couldn't breath. Changed the cat and problem solved. Two things can cause a clogged up cat. A motor running extremely rich or burning oil, or the element in the cat breaking down and clogging the outlet. I have also seen a clogged muffler from the cat breaking down and pieces of the element getting into the muffler.

 

@pofarm That is not the result of ANYTHING to do with your catalytic. Your engine was running so poorly that it fouled the catalytic. If im wrong, then tell us how your catalytic caused your engine to pass oil or unburnt fuel into the exhaust. Correlation is not causation.

Please, I do this for a living, you dont understand the way these systems function.

 

Cali wins the cigar on this one. The engine killed the cat. The cat can't kill the engine.