Three Catalytic Converters Blown Now

[bchilt]

Happy Holidays everyone,

I'm having trouble staying emissions friendly!

Here are the facts:

1) Original t-stat was stuck open causing car to run super rich, killed hi-flo aftermarket cats

2) Installed new 180 degree t-stat, new O2 sensors, and new spark plugs, new cats

3) Crappy weather in the Northwest = cold engine starts

4) 5 weeks later, I've lost another cat.

I'm getting 13.5 mpg on a stock daily driver. I know it's cold but that doesn't feel right.


Thanks in advance for the help,

bchilt

 

[Zero_chance]

For what its worth I live in the northeast and have never had problems with cats like that. Are they covered by any type of warranty? Is your secondary air system functioning properly? The air pump might not be sending fresh air downstream which will aid in the quick demise of catalytic converters.

 

[chaos254]

your gas mileage is way off.... I'm getting ~25mpg on the highway.

it seems like your running extremely rich. hopefully some of the other guys can chime in with some suggestions.

 

[BlownFiveLiter]

Pull codes. The check engine light doesn't need to be illuminated for a fault condition to be stored in the EEC.

 

[HISSIN50]

Agreed. Running excessively fat can wipe those out (the cat getting destroyed is the symptom. The cause is an issue upstream).

BTW, what does it mean that you're killng the cats? What is happening to them?

 

[bchilt]

I'm working on pulling the codes. I was convinced I had found the cause with the bad T-stat. Damn.

Hissin, killing the cats is just an expression.

 

[HISSIN50]

Hissin, killing the cats is just an expression.

No I was curious about how it was known the cats were bad (i.e. the matrix was getting clogged up, the spot welds were breaking loose, etc etc).

 

[GTA_V6_Mustang]

I get 25-28mpg highway and 19-20 with my city driving. you seem to be having poor luck with your cats. I have my high flow cats which require no use of an air pump so i have none, Have run it rich and have run it with 100LL and had zero issues with them. But if you are running cats that require the use of the air pump, use the air pump or try using ur air pump to see if the new cats last any longer. Also if you have excessive pinging or run under extreme heat conditions or even used contaminated fuel it could kill your cats.

Also if your not running an EGR system that could be affecting your cats. Out of curiosity, where in the mid pipe are the cats located, if they are located too close to the initial exhaust flow out of the combustion chamber that could possibly not helping your situation because I see your running after market cats on a different mid pipe which means you had to customize the use of cats on the midpipe if I'm correct.

 

[Pokageek]

Only thing that my exaust guy (very knowleagable) has ever seen kll cats is a bad tune. My suggetion? Take off the cats completely until you get the engined dialed in right and tested for a coupla weeks. It sucks man, cuz they are expen$ive! Same thing happento my high flow bullets!! rrrrrrrrrrrrr!

 

[GTA_V6_Mustang]

at work we get the idiots who put diesel in their cars when they where drunk and after we drain the diesel out and start the car, the cats shortly fail because of that. I had one 08 Town and County only 800 miles that wouldnt start cause the genious put a bit of diesel in and after i drained the tank and put fresh gas in it the cat was glowing bright Fing red from the diesel left in the cat and surely enough next morning had to replace the cat because it failed completely and car would not accelerate over 35mph lol. I actually love when ppl put diesel in their gasoline cars because thats easy money for me, lol.

 

[bchilt]

I don't know if you guys remember, but my car was damaged when moved from Texas. The guy backed my car into the ground of the trailer, damaging my X-pipe and the cats. The exhaust shop here cut out the old cats and put in new ones so I'm not concerned about location.

All my EGR stuff is on the car still. I agree with you guys 100%. I'm not doing anything else until I pull the codes. I ordered my Ford OBD-I scanner last night.

Just a little x-tra info for you. The X-pipe was installed in Texas in August. I had zero NOTICEABLE problems until I got to the Northwest. The main difference is the cooler air. BTW, my MPG (the 13 mpg) is city driving. I can't wait to pull the codes. It'll probably be a "no ***** code" like you're running rich

Thanks for the help and support everyone. I'll keep you guys posted as I find out more!

 

[BlownFiveLiter]

Ooh, I remember that story about the car getting damaged from the move now! Out of curiousity, have you checked your fuel pressure? There's the possibility that the return line got a little crunched somewhere with the other undercarriage damage, so your pressure would be too high and you'd be running quite rich.

 

[GTA_V6_Mustang]

Ooh, I remember that story about the car getting damaged from the move now! Out of curiousity, have you checked your fuel pressure? There's the possibility that the return line got a little crunched somewhere with the other undercarriage damage, so your pressure would be too high and you'd be running quite rich.

Your right that would cause that.