Clogged Cat

[cm581978]

What would cause a clogged cat on a car with my mods listed in my sig? I don't use a wotbox, so is it what is expected with a catted x pipe over time? I have a drivers side clogged cat, hence why I ask. Already ordered Thunderbolt 2.5 inch slip ons.

 

[ZmanM3]

After market cats.

 

[cm581978]

^ I assume they are normally pieces of crap?

 

[JeremyH]

I had a Kooks high flow cat give out when I was na. It unravelled and clogged my muffler on one side.

 

[Rasmus]

^ I assume they are normally pieces of crap?

I had a Kooks high flow cat give out when I was na. It unravelled and clogged my muffler on one side.

I know of two, local GT500s, and one GT, that ran Kooks high flow cats and ended up blowing the motor. As Jeremy said, the cats unravelled and clogged the exhaust, but their blocks ended up splitting.

I image that with boost the issue is more prevalent than N/A, but still, I don't like aftermarket cats.

 

[BruceH]

My guess would be that your tuner turned off the rear o2 sensors which in turn turns off cat protection. More than likely your cats got too hot and failed. I'd blame the tune, but that's me.

I've run factory and aftermarket cats with every setup I've had. Never had an issue but I'm of the mindset that Ford put cat protection logic in the tune for a reason, to protect the cats. Many tuners are much smarter than the Ford engineers and they know that it isn't needed. They usually will also recommend that you not run those crappy cats because they fail.

 

[cm581978]

I did have the tunes turn off the o2 sensors before Fdjizm installed the dummy sensors to pass emissions. I have 3 tunes on my SCT X3 and I think they all have the sensors turned off.

 

[Blxcklist]

Like previously stated, I'd say the tune most likely, however aftermarket cats have a history of clogging and causing serious damage.

 

[cm581978]

Could have been much worse though. I ordered 2.5 inch slip ons so I hope to get those on this week. I wonder how much power I'm losing with a clogged cat.

Like previously stated, I'd say the tune most likely, however aftermarket cats have a history of clogging and causing serious damage.

 

[JeremyH]

Could have been much worse though. I ordered 2.5 inch slip ons so I hope to get those on this week. I wonder how much power I'm losing with a clogged cat.

I would be a little more concerned about damaging the motor than power loss. For my 281 n/a I was down around 20-25rwhp from what I have seen from similar full bolt on cam setups. Didn't re-dyno after I fixed it though.

 

[JCCNY]

First I'm hearing of this. No issues with my Magnaflow catted x yet but this has me thinking!

 

[cm581978]

Just gonna have to take it easy until my new cats come in. Also, going to change the tune so that the rear o2's are on.

 

[Pentalab]

Just gonna have to take it easy until my new cats come in. Also, going to change the tune so that the rear o2's are on.

How do you know the driver's side cat is clogged up ?? Is it a change in exhaust note on the driver's side, or is it loss of power, or something else ? The story I got was the clogged cat temp will rise....provided the rear O2 sensor's are on in the tune. Both my jba cats (catted H + LT's) read identical temps on the obd port. Once disabled in the tune, I can't read cat temps anymore on the aeroforce gauges...and neither can the ecu. If a cat begins to clog up, is it blatantly obvious ?

 

[G.T]

i see a lot of tuners turn off cat overtemp protection to reduce the power loss when the PCM determines the cats are too hot, and richens up the fuel mixture to cool them down..

this can be fatal for cats if your exhaust does run really hot.

now long tube headers with highflow cats have 2 flaws that cause them to take a shit
1. well.. they're low quality
2. the cats will hang low under the body (unlike the factory units that are tucked nicely under) and a couple bottom-outs will be enough to get a crack started inside

if a cat fails, the back pressure will increase, your engine will run like crap.. there's a high likelyhood of you getting trouble codes of misfires on all the cylinders on the affected side.. and finally if you're boosted, your boost gauge will register higher pressure

 

[cm581978]

I ran at a track rental on Friday and my mph was down about 6-7 mph where I previously was at with less mods. It was the process of elimination basically, but Sat morning I took it to a shop where they confirmed the cat issue.

How do you know the driver's side cat is clogged up ?? Is it a change in exhaust note on the driver's side, or is it loss of power, or something else ? The story I got was the clogged cat temp will rise....provided the rear O2 sensor's are on in the tune. Both my jba cats (catted H + LT's) read identical temps on the obd port. Once disabled in the tune, I can't read cat temps anymore on the aeroforce gauges...and neither can the ecu. If a cat begins to clog up, is it blatantly obvious ?

 

[Fosters]

My cats smelled really bad the first time I pushed the car over 100mph. Within 2-3 weeks I took them off the car, they are very protected in my shed now. it seemed that they overheated to the point something was gonna fail sooner or later, and this was bone stock, so i figured it's safer/better to run an offroad pipe, even if emissions were to change later and I have to spend 2 hours every couple of years and put them back on.

 

[fdjizm]

Ehhh not a fan of cats.

 

[dark steed]

Ehhh not a fan of cats.

Yeah, but dogs are ok...

 

[cm581978]

I'm back in business! Had both cats replaced today with Thunderbolt 2.5 inch slip on's from Ebay. Fdjizm hooked it up! I haven't driven it yet, but I'm going to throw a new tune(with the O2 sensors on this time) and see if there is a seat of the pants difference.

 

[fdjizm]

Get out and rip on it, you will see the difference.