Hey Guys,

I've searched around a bit and found bits and pieces of my answer, but wanted to throw another PCM related question out to you all for a sanity check.

Alright, so here's the deal. My 97 RAM recently got the CAT gutted after a plug-up. Normal driving is just fine, smooth idle, no CEL, etc. I tow a boat every so often, and usually after a few minutes of towing, when I give the truck more than 75% Throttle (or WOT) it will throw the check engine light for an o2 sensor. Now I know that not having the CAT will trip the rear o2 sensor, that part doesnt really phase me too much.

I can get an o2 sim, or just put a high-flow CAT on, thats simple enough.

I am more interested in what the PCM thinks/does when it throws that code, as it usually runs kinda rough (presumably rich) until it either dies, or I shut it off, and restart it, then it seems to be back to normal, and after a few drive cycles the CEL will clear itself until the next time I hook up to the boat.

Anyone run the fastman o2 sim and still had any CEL related issues when towing? Thanks guys!