Quick summary. Truck info in the sig. Had my 94106s put on in 12/09. No check engine light/ no codes until I did my true duals in 12/10. At the time they touched up the welding around both cats. Starting throwing the P0420 code for bank 1 cat almost immediately afterwards. Threw that code once every 1-2 weeks. Went back a few weeks later and they touched up some more. Started up this evening and check engine light was back on. Now it's both banks.

Now what are the chances both cats are bad? My theory is that when they went back in and touched up the welds around the cats it somehow fouled the 02 sensors but I would love some more opinions. And is there any way I can prove this theory easily?

Thanks. But my dual Magnapacks still sound awesome as far as I am concerned.

 

either bad O2 sensors or the new setup causes the sensors to read too far off of what they are supposed to from the factory. Gotts has a o2 sensor code fix somewhere on here.

 

gotts o2 mod

 

You sure there are no leaks? I got a P0430 back in December. I had fouled plugs and later a bad coil. Ford said my truck has an engine skip maybe due to a bad cat. Gonna have it tested. Already about a new 94106. Check your tune, mine was bad. Pinging. I think it fouled up my plugs. I am even nervous on the 93 performance. I wish I could have easy access to a dyno. I threw the code nearly a month after the plugs were done (so end of January) and it came back 2 times after that. RIght around inspection time too. I thought I was going to fail. I passed and it has been off since, but the truck does have a slight skip at idle. Light has stayed off for almost two weeks now

 

I think I remember 08FX4 saying once that he did the Gotts Mod because his started throwing codes and the Gotts didn't fix it. Don't hold me to it though. I am well aware of the Gotts though. I might data log some and send it to Bill at PHP. The last time I was there to have it welded they put it up on the rack with me in it so that I could rev it and they welded up the leaks. There is one troublesome spot though. I might get them to check it.

My truck is an '08 with 33,000 miles. I wouldn't think bad plugs and coil but it wouldn't suprise me either. And speaking of the tune. Watch my compilation video in the sig. When I submitted for the Exhaust Contest I noticed a screeching sound on high revs/rpms. At first I thought it was a rattling heat shield but now I am not so sure because I crawled underneath and everything is solid.

 

A bad tune can foul your plugs... that's my point with the email tunes. They can't see anything. You know? I'm so nervous about it now. You have no idea if it is too lean or rich. I think my custom tune fouled the plugs and it ruined the cat as did the bad coil. My code comes on every so often, so I am wondering if it is just going bad. I may save for a dyno tune because I just don't think people realize how risky these email tunes are. Just think about it: Someone in a remote location is writing essentially major settings for your engine that doesn't know your truck. Every truck responds differently to mods, so how safe are they really? Pretty risky if you ask me. You have no idea if it is even running the best it can let alone within the realm of how it should be. Without a dyno tune, the tuner can't fully see how your truck or any vehicle for that matter, is doing.

 

And also, with PHP (and I do have a Gryphon) no one else can alter your tunes. You're stuck. It took nearly a month for the tune to get edited. I never ended up using it. Too scared to. Dyno tune with SCTX cal 3 is really the safest and most global way the more I read and experience

 

Yea, It's definitely not a bad O2 sensor.

 

I know the codes it is throwing are for when the front 02 and the rear 02 readings are too close together. So if the cats are bad I can deal with that. I don't think it's the tune because I had the gryphon running for a month before the duals went in and no code.

 

Gotts o2 mod.

 

how do you know that? Been around long enough to know you may be right. I;m just wondering how you know.

 

Short explanation. - Faulty HO2S sensors do not produce the DTCs P0420 and P0430. The sensors must all be tested and shown to be reliable before the Catalyst Monitor can be called by the Executive.

That's all I'm good for at the moment.

 

Do the gotts mod- I did it about two years ago before I knew it was the "gotts" mod- spent like six bucks at autozone and about 30,000 miles later still no CEL! And my truck was throwin the code 2-3 times a week before...