Fuel smell question

I just replaced my catalytic converter today with the flow master because the Toyota dealership said they were 99.9% sure that I needed a catalytic converter it was restricting. But I had a fuel smell coming out of my exhaust and my question is what could be causing the fuel smell. It is a 2004 Toyota Tacoma 4 x 4 V6 and it idles perfect runs perfect however the fuel smell out of the exhaust. No other code is coming up in the engine but I am thinking the water efi sensor or mass air sensor. My truck looks like it has 25,000 miles on it but it has 219,000 miles on it... Anybody have suggestions on what could be making the truck burn rich or smell Rich coming out of the exhaust pipe before I spend a ton of money on changing every little thing ? Thank you

 

Google: toyota 3.4 "running rich"
Lots of hits to research.

 

welp. smelling rich. if the cat is truly clogged, more exhaust may be shooting out of it than it can handle in the free'er flowing parts of the honey comb. does it still smell like gas? and are you checking for gas smell when the engine is cold, or warmed up after it's been running a while.

now for a truly rich burning situation. youll need a scanner and also need to watch the fuel trims and air intake levels both measured and calculated. that way you can see if everything is matching or something is out of whack.

but the only real way you would have a rich situation is if your front o2 sensor is bad and reporting everything being ok when it isnt.

 

A failing temp sensor can richen [sic] the mixture once it goes into closed loop. Does it start easily from cold and then, once warm and shut off, crank a bit longer then normal?

 

if it helps, i have the 2.7 mine was running rich with a fuel smell recently, turns out my maf was dirty (truck sits for awhile during the summer) had black fuzzy stuff built up in it, cleaned that and replaced my air filter and was good to go, hope that helps

 

Thank you

 

No Problem man, let me know how it turns out

 

My 2001 2.7l does the same thing, fuel smell but only when it is cold. Once it is warmed up the smell goes away. No cel, truck runs good with 248,000mi.

 

mine did the same thing, then i just did what i mentioned above and it fixed my problem but to be safe check the plugs and wires also the cap and rotor too just to be safe, also i think its the egr, theres filters in there you just take the cap off to clean or replace those little filters, that may help also