91dohcvtec

Current Setup:
- Ls - Vtec
- obd0 PW0 for now/ with slightly chipped rom
- 11:5:1 ish compression using Pr3 pistons
- stock b16a1 head
- Stock Catalytic converter
- aftermarket header & intake

I think my catalytic is going bad, so far ive had no engine codes, everything has been running smoothly. I have a stock converter installed. one night i took it for a spin and ran it hard for a few mins along some backroads. Then all of a sudden engine bogs for a split second and engine light comes on......reads Cel 67??? I haven't seen a code that high before. Maybe the ecu is making this up. This usually happens once everytime I take the car for a drive, after 10-20 mins of driving and and I just turn the car off/on and then it's fine. Too make the long story short....

The symptoms:
- rough fluctuating idle, checked/cleaned eacv, fitv, checked all hoses for leaks.
- engine sometimes bogs for a sec at low speed
- engine/engine bay is a little hotter than usual
- feels like there is a little leak/buzzing noise from midpipe area.

I'm thinking now that there is higher compression + aftermarket header, It's just restricting the exhaust flow. Maybe I should invest into a high flow? I'm take a look at it tommorow.

D.T.P

Bang the cat around and see if you hear rattling. If so, time for a new one.

Darrylmcl

iTrader: (2)

dont know if the 91, is like the 2000, but recently the gaskets between the cat and downpipe (midpipe) and the gasket between the downpipe and manifold have worn down due to wear and tear... had a rather annoying sounds rattling at low speeds, also you could hear the car exhausting from underneath my feet, replaced the gaskets and all was back to normal.