Cat Delete?

[mprice1234]

Hmm, quick question, if you're driving towing a trailer up a steep hill and there's an odd smell coming out of your tail pipe how the heck do you know? Do you normally smell tail pipes?

 

[CoronaRaptor]

Hmm, quick question, if you're driving towing a trailer up a steep hill and there's an odd smell coming out of your tail pipe how the heck do you know? Do you normally smell tail pipes?

Well smarty pants, lol, we pull over on the truck stops (there’s plenty on these steep mountain roads) right away and you can only smell it on the right rear of the truck and as you put your nose down to the exhaust outlet, it’s very strong. Remember, we tested this several times, didn’t want to make a fool of myself, but let’s see if I can, so keep coming up with some ideas.
I have heard if you don’t run cats, the truck can smell stinky out the exhaust, anybody??? I mean, I’m thinking my cats might be blown apart inside from all that power out of this 6.2 litre boat anchor?

 

[pat247]

The sweet smell indicates antifreeze to me.

 

[Jakenbake]

I have heard if you don’t run cats, the truck can smell stinky out the exhaust, anybody???

Have you not smelled a vehicle without cats before?

 

[CoronaRaptor]

The sweet smell indicates antifreeze to me.

There's no loss of antireeze or any contamination in the engine that I have seen.

 

[CoronaRaptor]

Have you not smelled a vehicle without cats before?

My mustang doesn't have cats and it is a lot stronger smell than my truck, but doesn't have any burnt smell, just more of a raw fuel smell (its a higher HP engine). The Raptor smells more of a burning brake smell and a gas smell I guess. I say sweet, not like chocolate cake but more like almost a sweet aroma that only a gearhead would enjoy, IDK, it's really hard to describe. IT'S ONLY when the engine is under a heavy load, when it's at max torque, you can take off full throttle at a stop light and burn rubber but it won't smell like this, just when towing the trailer up hills. I thought it was my transmission at first, but then we definitley sourced it to the exhaust smell, so that's why I thought about the cats as the exhaust was put on 11 years ago and I don't know if cats last a lifetime or not. And if I can just take them off and the engine runs fine, I'm good with that, but if they are not the problem and there isn't a problem I'm good with that as well. Maybe I'm just wasting all your valuable time on this thread, LOL.

 

[Jakenbake]

My mustang doesn't have cats and it is a lot stronger smell than my truck, but doesn't have any burnt smell, just more of a raw fuel smell (its a higher HP engine). The Raptor smells more of a burning brake smell and a gas smell I guess. I say sweet, not like chocolate cake but more like almost a sweet aroma that only a gearhead would enjoy, IDK, it's really hard to describe. IT'S ONLY when the engine is under a heavy load, when it's at max torque, you can take off full throttle at a stop light and burn rubber but it won't smell like this, just when towing the trailer up hills. I thought it was my transmission at first, but then we definitley sourced it to the exhaust smell, so that's why I thought about the cats as the exhaust was put on 11 years ago and I don't know if cats last a lifetime or not. And if I can just take them off and the engine runs fine, I'm good with that, but if they are not the problem and there isn't a problem I'm good with that as well. Maybe I'm just wasting all your valuable time on this thread, LOL.

All the catless vehicles I have been around have smelled different. 4.6 2 valve, 5.7 hemi, 6.2 Chevy LT1 (i think), etc. fuel injected vs carb, but they all kinda smelled the same.

Cats lasting a lifetime probably depends on the definition of lifetime.

I’d say you have a pretty good idea of what a catless vehicle smells like and would be able to pick that out.

 

[CoronaRaptor]

I was hoping somebody that maybe bought the SW exhaust without cats noticed the smell or not. I know there used to be some people on here, but they probably all died or bought a trx.

 

[smurfslayer]

I have smelly exhaust when I tow my trailer up long steep hills

Maybe eat some more fruit?

 

[FordTechOne]

It almost sounds like it’s running lean and you’re smelling the exhaust becoming (extremely) hot after being under load. With LT headers, you’re increasing the volume of air that can be pushed through the engine during the combustion cycle. More exhaust out allows for more intake air to fill the cylinder during the subsequent intake stroke. More air requires more fuel, and the PCM can only compensate so much. With the factory exhaust manifolds, that increase in exhaust flow (from the LTs) is theoretically impossible, so the PCM will in most cases not be able to properly account for it. This is especially true under full throttle, where the system reverts to open loop (default tables) instead of closed loop (O2 readings).

You may want to consider getting the truck tuned to compensate for the LTs, especially if you’re going to be running it hard. Lean conditions blow engines, and I don’t think you want to join that club!!