I've seen it work, problem is with a stock tune after a time the PCM adjusts to the cooler thermostat and adjusts the mix and you get the CEL back. But it MIGHT get him through an inspection. Obviously the non-foulers are the way to go. Was just trying to come up with a cheap/quick/temp fix for someone who may not be inclined to make non-foulers and climb under the truck...

 

Well I can tell you that your thermostat method doesn't work from first hand experience.

 

It actually will work in some cases IF your CEL is caused by exhaust gas temps being too high. But won't if the CEL is caused by low O2 content. I've seen it with my own eyes before I learned the non-fouler trick.

Again, the cool thing with non-foulers is that by physically moving the sensors out of the direct exhaust flow they fix both situations...

 

Don't really understand why you keep pushing a solution that is in your own words is not a definate solution over one that is. Especially when your suggestion is more work and more expensive and as you said, only works in some cases where the non foulers are cheap, easy and a proven solution to this code.

 

So would a PCM reset help hasten the lower thermostat method to maybe working?

 

Not pushing it at all, but I've known people who are a lot more comfortable changing a thermostat which is legal, whereas the non-foulers are a not and in some states can get you a fine for altering the exhaust system. In this case, since the guy did purchase cats, thought it might be worth mention. For those people, it's worth the $8 thermostat and 15 minutes to try.
Personally, I've done the non-foulers about a dozen times, once on my own 2nd Gen Ram where I went true duel and cat-delete - which is illegal, LOL...

 

Thanks again for the help guys. He installed the non fouler(spacers) and hasn't thrown a CEL for over 100 miles. Fingers crossed. I tried to post pictures but not sure if it worked(hard to do from my phone). Anyway I appreciate the fast responses and detailed suggestions.

 

Glad to hear the non foulers worked for you.