Originally Posted by TRY...M3
Well Dave since your the expert on O2 extenders can you explain why my car went into limp mode with them on and as soon as I took them out my car immediately left limp mode. I spoke with a lot more people that know the M3 in and out and we came up with that being the solution. I'm speaking from experience not jus your 2 cents. I know a few people that use them on evo Xs an have no problem. But were not talking about evos. I went through 2 weeks of problems with my car just because of the extenders and I don't want it to happen to someone else. And I know these are capable of doing more damage then goof in most cases.
You need to provide more info for Dave, or anyone else, to address your question. Who installed the extenders? Who made the extenders? What kind of exhaust? What codes got thrown when you went into limp more?
If I had to take a wild guess on your case, I would say they installed the extenders on the primary o2's or, in installing them on the rear o2's, they were not properly grounded. But it's a crap shoot without more info.
In the case of the fabspeed extenders, I have heard of zero incidents where they caused limp mode. I have heard of mixed results in terms of how long the car will go before throwing a code. Some cars don't need the extenders at all. Some will go 3k, others 10k, etc.