Thanks for the update. It would be nice if the mfr/seller of these am parts fully disclosed the add'l steps that 'may be necessary' when installing these parts on this platform. Some folks might chose to stick with stock headers to avoid the parts/codes/troubleshooting chase.
I see nothing "odd" about the CEL situation, clearing the codes will turn on the light, and then it will take a few drive cycles for a code to switch from "pending" to "active", which will turn on your light. As stated above, if your OBD reader is not set to read both left and right banks, it will come back clean unless it sees an issue with the computer it is actually talking to. The mini-cats, which were most likely the solution (can you ask your mechanic for specifics?), were suggested right away and not taken into account. Not trying to be rude, but I just don't understand when someone asks advice from people who know, drive, modify, and repair these cars, then ignore the advice, and continue to have the same problem and ask the same questions.
Thank you Lee. I had an issue with FabSpeed exhaust tips for my wife's 430. It took a number of calls but they eventually did the right thing. The sequel to my first novel is in final edit and I expect a publish date prior to Xmas.
The avg f car consumer will most likely not expect to buy a $3K set of headers, pay $600 for installation, THEN have a few possible outcomes including: 1) just leave the CEL on it is normal..... 2) no CEL for a while, then CEL, and trouble shoot..... 3)immediate CEL....... and start throwing parts at it.... mini cat's.... might solve it..... might not.......... if perspective buyers where shown the decision tree of the outlay of cash, the performance improvement, AND the steps to 'possible' success they might just stick with stock headers, and if they fail, find another set of used stock headers. Hopefully someone will develop a tuning workaround to avoid this madness....... I know of no other platform that requires such finicky CEL steps for simple header install......... <<<<whine mode off>>>>>> I feel better.
I put the Fabspeed headers on about two years ago. Immediate CEL - Cat efficiency both banks. Installed O2 extenders. Got rid of one code but one CEL for the right bank would pop up often. Put mini-cats on. No issues now. Going on a year and 2,000 miles.
you need to move 2 of the 4 the oxygen sensors to a place after the main cats. when you changed headers you now only have one cat per side not two, see a 1999 360 cat for location the headers work great and the car will still pass smog
