Changed plug now only throwing P0420. Wondering if i should have head pulled and checked.

 

Unfortunately if the steel plug is firecut that badly, the aluminum head is probably worse. It would have been better if it had just blown out of the head early on as most do. Then you would probably be looking at a helicoil repair. This may require a new head depending on the damage. You can see aluminum from the head in the threads. I hate to be the bearer of bad news but it's very unlikely it can be saved.

 

It has been running fairly decent for a couple weeks. I was going to replace the catalytic converters because i am still getting P0420. Should I get the head pulled first?

 

I would pull the head to get to the root of the problem. It's definitely hurt as IHC mentioned.

 

Prolly should check your ECU for water damage as well....

 

would it be a bad idea to get a used head on ebay for 250$?Or should I go to local junk yard?Cant have car down for a long period of time.

 

How much does it usually cost to have a head machined?

 

If the head is firecut you're way past the point of machining.

If there's no misfire now you have little to lose by running it as is.

It's pretty normal for a misfire, especially over time to kill a cat. You're getting raw fuel into the cat which is bad for it. Looking at the plug it looks like it was firing occasionally. Maybe arcing to the sides. I'm surprised it didn't kill the coilpack since you essentially had a huge gap. You can go ahead and replace the cat (make sure your 02s are ok first) and run it.

Hopefully that electrode didn't hurt anything when it broke.

 

do you think i need to replace both the upper cats or just the one that was throwing the codes?
Should I replace both o2 sensors pre and post?
Are aftermarket cats as good as factory cats?

 

And should I get a Jpipe while im in there?

 

Pulled the plug. It was not in all the way, I was scared to put torque on it. Used torque wrench and put it back in seemed like it went a lot further in.

 

replace head check ecm for water damage