An exercise in overthinking - Junits15's street build

[Duece McCracken]

I cut the center muffler a bit shorter than the x pipe by accident, so the longer x pipe pushed the rear mufflers back. This caused the passenger side exhaust valve actuator wires to jam into a pinch weld. Eventually wearing through the insulation, shorting to ground, and giving the “exhaust mode selection not available” error.

I cut another half inch off the x pipe on both sides re-adjusted and now it’s good.

before:

after:

and a glamor shot

And my old girl

You big dumb dumb face!

Hopefully you didnt short them out. They are a bit pricey iirc.

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[junits15]

You big dumb dumb face!

Hopefully you didnt short them out. They are a bit pricey iirc.

It’s alive again lol, all the exhaust modes work!

yeah I felt pretty dumb, I should have checked the size of the piece I cut out lmao

sounds mean tho

 

[Duece McCracken]

It’s alive again lol, all the exhaust modes work!

yeah I felt pretty dumb, I should have checked the size of the piece I cut out lmao

sounds mean tho

I still need to adjust mine, lmfao! My setup is a bit custom, and It currently has the mufflers pushed out a bit far. Only way to fix it is to chop up the Borla pipes. Shiz, I also have those borla warranty mufflers to install.

I should get my shit together.

 

[junits15]

I still need to adjust mine, lmfao! My setup is a bit custom, and It currently has the mufflers pushed out a bit far. Only way to fix it is to chop up the Borla pipes. Shiz, I also have those borla warranty mufflers to install.

I should get my shit together.

Yeah you should lol, exhaust work is just a pain without a lift though. So I understand why you're dragging your feet.

The results of your modifications directly effect what I do to my car ;)

 

[junits15]

also, I popped a bank 2 catalyst code today, which is just complete BS the car only has 22k miles on it and 20k of them are 100% stock.

I kind of don't believe its real, if this bank 2 catalyst is actually failed I'm gonna be really surprised. I'd probably have them replace it under the emissions warranty, I'll have to remove the WMI tank from the trunk and the injection plate but that's easy peasy.

I'm not gonna rush this, I don't have an inspection until January, I'll likely just disable the code until I get the time to fix it correctly.

 

[Duece McCracken]

also, I popped a bank 2 catalyst code today, which is just complete BS the car only has 22k miles on it and 20k of them are 100% stock.

I kind of don't believe its real, if this bank 2 catalyst is actually failed I'm gonna be really surprised. I'd probably have them replace it under the emissions warranty, I'll have to remove the WMI tank from the trunk and the injection plate but that's easy peasy.

I'm not gonna rush this, I don't have an inspection until January, I'll likely just disable the code until I get the time to fix it correctly.

I wonder if your meth experiments shorted it out.

 

[junits15]

I wonder if your meth experiments shorted it out.

I’m wondering that too, but it’s hard to say. I haven’t been running meth very long, only spraying at WOT.

Who knows! That’s the nature of experiments

 

[junits15]

Yeah bad news, it set the P0430 again, and even worse that's the side with the welded cat. :| I don't think my experiments killed it either, I think its a legitimate crib death.

There are three things I was doing that could damage the cats.

Misfires:
During methanol testing, I was battling with some high RPM misfires. On a WOT pull with methanol engaged, I could get misfires enough to trip the CEL above 5000RPM. The car would basically fall on its face if there was too much spray. However, every time that happened, I aborted the pull, and turned the WMI off for the remainder of the drive until I could tweak the settings. Bear in mind that my WMI only sprays when the TPS>95%, so for almost all driving situations the spray is off.

Continued misfiring can kill a catalytic converter, however this was not sustained misfiring, this was brief bursts of misfires that only occurred while I was testing the system. Does that seem like enough to kill a catalyst? My instincts are saying no.

Burble:
My burble is stock Bullitt burble, 100% identical settings. Those cars have the same headers and cats as mine. Not a chance that this was the issue.

WOT enrichment:
I made WOT enrichment come in 500RPM sooner, and get 2.5% richer above 7000RPM, there's not a chance that did it, the Roush SC tune is richer than that. The enrichment is stock values for 95% of the RPM range, and the 5% of the RPM range where it is richer, its only 2.5% richer.


The emissions warranty is 80k miles or 8 years, so I'm in the clear on getting a replacement. Though I'm kinda stunned that it happened, I've driven a lot of cars and I've never seen a cat fail this early. My brother had made a comment the other day that the car smelled "fuel-y" and I assured him that the cats are stock so it must be normal lol. Oops, spoke too soon!

 

[engineermike]

I don’t think wot enrichment fails cats. The fuel doesn’t stay in the cat long enough and the egt governs the cat temp.

 

[junits15]

I don’t think wot enrichment fails cats. The fuel doesn’t stay in the cat long enough and the egt governs the cat temp.

Appreciate the response Mike! That’s one more thing I can cross off the list.

That only really leaves excessive misfires as a potential cause. I would hope that an excessive misfire event would trigger the cat protection routine, though I am not sure.

In general though, even without knowing if misfires trigger cat protection, my thought is that there are failsafes in place that should have kicked in if the cat was actively being damaged. They didn’t engage as far as I can tell.

So I’m leaning towards it being a real premature failure, maybe a cracked substrate. I intend to stay catted so I’m going to repair this correctly eventually, for now I just need to get through my inspection.

 

[engineermike]

Someone is selling a set of stock cats for cheap right now on the forum.

I’ve seen several failed stock cats and most are cracked or even chunks missing. The stock cat bed is high cell count (750) and very delicate due to thin ceramic honeycomb.

 

[Duece McCracken]

Appreciate the response Mike! That’s one more thing I can cross off the list.

That only really leaves excessive misfires as a potential cause. I would hope that an excessive misfire event would trigger the cat protection routine, though I am not sure.

In general though, even without knowing if misfires trigger cat protection, my thought is that there are failsafes in place that should have kicked in if the cat was actively being damaged. They didn’t engage as far as I can tell.

So I’m leaning towards it being a real premature failure, maybe a cracked substrate. I intend to stay catted so I’m going to repair this correctly eventually, for now I just need to get through my inspection.

Time to go meowless long tubes...

 

[junits15]

Someone is selling a set of stock cats for cheap right now on the forum.

I’ve seen several failed stock cats and most are cracked or even chunks missing. The stock cat bed is high cell count (750) and very delicate due to thin ceramic honeycomb.

That's a nasty failure, probably what I have going on :( What's the history like on these failures that you've seen? Stock cars? or modded?

This is my first time blowing a stock cat, a damn shame really.

 

[junits15]

Time to go meowless long tubes...

The noise would send me over the edge lol

 

[engineermike]

That's a nasty failure, probably what I have going on :( What's the history like on these failures that you've seen? Stock cars? or modded?

All I’ve seen were supercharged.

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