wag1965

took my stock truck, one year old, for its first test today. On the back of the certificate they give you it explains what they check here in TN, in the counties that require it. On 2002+ diesels they check the fuel tank caps and do an OBD test. My question is, if I understand correctly, when you do a tuner and deletes, the tuner , as part of its program, lies to the ECM and tells it everything is within specs, so no codes are thrown. If that is the case, and all they do here is an OBD test, since all the info that the ECM recieves says everything is ok, then would'nt a deleted truck with a tuner pass here because the ECM would pass on to their device that all was within specs? Iknow a dealer can tell when you have been in there, but these testers just use a device to look for codes, seems to me that if they found no codes, you would pass. I know other places are a lot different, but given this info, am I correct onthis? THANKS

New2Diesel

It took (4) places in North Carolina less than 10 minutes to fail my truck due to deletes. Obviously on the 5th attempt I was good to go.

My theory was, if at first you do not succeed, keep trying until you get some good ole' boys to hook you up. It was worth the 5th attempt.

Beast2B

Did they fail you on the visual inspection or did they see something on their scanner?
I had a Smarty on my 2001 that had a 1/2 power setting. With my mods and using that setting I passed fine. No smoke, no codes. It did take a couple hundred miles and several start/stop cycles for the ECM to get all of the emissions registers to a point where the smog computer would pass the truck.

wag1965

What I am thinking is now that I know they do not raise the hood, or use the mirror on a stick to look, I might could get by around here a liittle easier than some places. They are a few full time test places, and a few mobile ones, they are not service centers or dealers, so they will not look any deeper than what they are told to, and that is just an OBD reading. What I am thinking, is it will depend on what the tuner does to handle codes. If a tuner tells the truck certain sensors have been removed, ignore them......they might pick up on that and I would need to UNDELETE each year. BUT, if the tuner tells the truck all sensors are in place and working right, even though they are gone....fooling the ECM... then I THINK IT SHOULD ALSO FOOL THE OBD TEST. If that is the case I would not have to change each year. That would be my main question...do the tuners shut off sensors so it will not code, or do they send like a false signal to avoid a code....... and do all tuners handle this the same way?

Beast2B

They didn't do any investigating in my ECM when they smogged my 01. They look for codes set and make sure all of the emissions registers are operating. Slight correction -- it's not 'someone' looking at the OBD, it's actually connected to the computer that's directly connected to the state's system!

New2Diesel

The places that failed me were for either a visual inspection of the exhaust system or because I had my Mini Maxx plugged into the OBD2 port. They have to access the OBD2 port, but, the place that passed me did not access the OBD2 port and could care less about climbing underneath the vehicle. They just wanted the costs associated with the inspection and their money. Fine by me, I was glad to pay them. Anyway, like I said, gotta keep trying.

Also, for the record, I do not recommend this method but it worked for me. I actually am going to have my vehicle re-registered in a month on my Dad's farm in Alabama. No state inspection plus I will have a RED tag that says "Farm Truck" on it. Granted I will not be driving the truck in Alabama but I will be able to use Red Gas in it and that will save me some duckets.

Blake Clark

Brian better research that. As far as I know of, In Louisiana, even though your sporting farm tags you cant run red on the street.

dragabusa

I always read about voiding the warranty when doing the deletes and H&S.
This may be a dumb question but, it's voiding the Powertrain side only and not the bumper to bumper part right?

Rednecktastic

Yeah you void the powertrain and emission warranty if you tamper with the emissions equipment and controls.

bdewey

I have taken my truck in for bumper to bumper work with my deletes on. I still got work done as long as your not taken it in for work where you did the modifications.

dragabusa

Thanks for the replys. What I'm hearing is what I thought but just wanted to be sure.
Gonna go to the Motor Vehicle this week to see if they will give me a print out of just exactly what they will test for new tags.
I think I'm good here in Delaware for no OBD or emission tests. I'm over the 8500 MGVWR and its powered solely by diesel.