Just fyi guys. If you guys need cats. I have them available. Just pm me and i will get you a price for them. I also have a mis fire in cylinder 3. It was oil.

The Dr!

 

 

 

 

usually imt orings. The back lower one drips right on the exhaust. But hey while you have it all offreplace it all cause theyre all the same age and mileage

 

 

 

Last thing to do now - check fuel trims once they've had a chance to settle.

 

So far, so good. P0305 and P1315 are gone. Fuel trims look good. No leaks so far. P0420 still there, but it has been intermittent. I still think the misfire caused the Catalytic Converter to get gunned up. Now that it is fixed, I’ll try to “clean” it again and see if I can get it to go out again. We’ll see.

 

check if theirs a leak at gaskets at the cats ,other wise you may need a new cat
some people has had luck running seafoam through the vacuum of the brake booster to clean cat if its minor

 

• First: Used half a bottle of seafoam spray directly in the catalytic converter. I took out the upstream O2 sensor and used an endoscope to look down into the CAT. I saw that the media was in good shape, but looked dirty. As stated above, I think it was form the contamination and soot from the misfire on #5. The seafoam spray came with a long spray straw that let me a good position and move the end around to get as much coverage as possible.
• Second: I got a narrow hose and poured about 1/2 bottle of liquid seafoam directly into the CAT.
• Third: Drove the car 3-4 miles to a remote parking lot.
• Fourth: Sprayed the rest of the seafoam spray into the air intake (found a video on YouTube).
• Fifth: Poured the rest of the liquid seafoam into the brake vacuum tube who,e car was running (like done in you tube videos and in advice from the forum.
• Sixth: Let it smoke like a forest fire.
• Seventh: Drove it for 40 mile then and reset the OBD code.

It it has been clear ever since. I’ll keep you posted if things change. Wish me luck!!!

 

Update since Oct? P0420 still gone?

 

 

I hope it stays off for you.. I did not get one on mine until a recent replacement of spark plugs and Coil packs.. after the mechanic put everything back together my P0301 Code was off and I suddenly got the P0420.. the car runs great though.. so I'm thinking that since it wasn't there before, the mechanic must not have installed the manifold back correctly or may have displaced the gaskets when reinstalling. It doesn't seem likely that my catalytic converter would suddenly fail from pulling the manifold off and putting it back on.. LOL ..

I haven't checked it yet, but I need to check the manifold bolts to make sure they're not loose.. Since 3 of the bolts are not the same length, I am crossing my fingers that the mechanic understood this and did not put them back in the wrong order.. of course when I ran the car back up there they were less than accommodating in trying to help resolve the problem.. they already have my money so "it wasn't them," despite having the intake manifold off (intake manifold leak being one of the reasons for a P0420).

Waterpump! If it's not one thing if it comes another right!?

 

 

From what I've read, the misfire causes incomplete detonation of the fuel which accumulates in the cat. It's causes the cat to get too hot in which is what damages the precious metals on the honeycombs inside the cat.. of course the longer this is allowed to continue while driving the car, it can actually cause sufficient damage to make the honeycomb crumble overtime.. and this will actually block the cat.. so you can have failure of the cat without any blockage, because the O2 sensors pick up that the cat is not doing it's job, which is what generates the P0420. Or you can get to the point to where the honeycomb fails and completely blocks.

Regarding the water pump.. smart move because the car doesn't always cooperate with problems during perfect weather.. mine didn't either.. lol..

 

 

@David Thornton I recently replaced the Intake manifold gaskets and spark plugs and IMT O rings, I am getting the P0420 as well. Did you resolve yours?

 

No the car is been running fine with great gas mileage so I decided to wait until it warms up in March.. I may go ahead and remove the manifold again and replace the upper gaskets again, and the lower gaskets.. because the code did not show up until after the tune up, I really don't think it's the catalytic converter..