I see something there, but it looks like a shadow. Anyway, Lee, if you're interested in the ZZP downpipe, you can call and ask them about it.

 

The main difference is the guarantee. CARB says it must be guaranteed for 5 years. I am probably wrong, but I was under the impression any welded on things are not permitted.

 

Just stricter requirements and more precious metals to last longer
https://10secondracing.com/pages/epa...the-difference

One mechanic told me about various high heat sealants he has used on the flex pipe Just concerned if they harden and make the pipe rigid so it stops flexing

 

A follow member lives in NY posted this handy how to

https://www.chevyhhr.net/forums/how-...ex-pipe-31536/

 

I bought one of the cheap cats-EPA not CARB-and had it installed on 10/7. Right before I took the car in, I had 3 codes: P0171, P0420, and P0300.

Good thing I didn't try it myself. The 3 bolts by the exhaust manifold and the oxygen sensor all came out easy. But the 2 bolts by the resonator.....forget about it. Even heating the bolts didn't help He had to melt the nuts off.

The car is running much better, but still has a problem As soon as I started it up, you could hear it sounded different-possibly less restrictive cat. At first I got 2 codes:P0171 and P0420. I reset it and drove for a while then got 2 codes: P0171 and P0300. I wanted to drive for a while to see if the computer would settle in. SInce then I only get the P0171.

I have already cleaned the MAF and it didn't help. The car sounds like it has a slight miss at idle and under acceleration, but it is not in limp mode anymore. It kind of sounds like the old Volkswagens did with their pancake motors.

Any ideas?

 

Like when you forget to put the gasket on the flange?
The P0171 might be responsible for the trashed cat.

 

I was with the mechanic the entire time and helped him holding the pipe, etc.

The both gaskets were definitely installed. And my problem was a cracked flex pipe. The original cat was fine. I saved it so I can replace the flex pipe if the new cat fails the emissions test.