To Old School, I have the software version numbers for you. There are seven total.
12593555 12591932 12592575 12582850 12582858 12593772 and 12593772.
This thing must revolve around GM’s CAFE numbers. The problem I have with this idea is that I believed your vehicle was not included in the mix (because of its weight)in figuring a companys CAFE. The phrase “teir 2” is a phrase used in grouping vehicle according to emissions.
Does GM want to produce more vehicles in the “teir 2 catagory”. If the vehicle is included in figuring CAFE is this the reason it is equopped as it is? Just don’t know.
After todays announcement of new rules for CAFE (thats rules not laws)are teir 2 vehicles prefered or how are they affected.
Here’s the deal, most Chevy trucks when “batch” produced, come with the “NC1” option which is Cali. emissions. Since my truck was special order, the “NC1” order code was deleted and a different code “NT9” substitutes in its place, meaning “Not California” legal. “FE9” option is also on the build sheet. So I can not ever sell or register this truck in California.(not a problem) As a matter of fact, per Robert Ortloff Jr. at Liberty Pontiac/GMC, this truck has 80hp more since it is not choked down with extra emissions equipment. Second, Chevy customer assistance lied to me when they told me that this was a light duty truck with a heavy duty engine. Since the GVWR is 9200lbs. it is a medium duty truck with a heavy duty engine. The cutoff is 8600lbs. or greater. So because of its weight rating and non Calif. emissions, it only needs 2 O2 sensors. I think what caused this whole problem from the git go was that I had a special vanity license plate on this truck. The license plate originally came from a light duty GMC pickup truck, and was transferred to this truck. So the 2005 Silverado medium duty had a registration of only 6000lbs. making people think the truck was light duty. A vehicle over 8600lbs. is not subject to emissions inspection anyways, only safety inspections. So now it is correctly registered in N. Carolina for over 9200lbs. and I should not ever have this problem ever again. Here’s a interesting sidenote, the vehicle build sheet shows X88 Chevrolet conversion. This truck was originally a GMC, converted to Chevrolet clothing! Thanx for the information that you folks provided.
I consider myself to be competent in the engine performance and OBD2 system theory and diagnosis area. I can’t see how 80hp comes from no post cat. sensors,there must be more going on. That where I come back to different software but, it would be interesting to know all differences that recovered this 80hp from a choked up model.
People should be flocking to this extra 80hp model. People pay thousands to modify their vehicles and don’t get that kind of return.
Just telling you what I was told by a dealership. Was told that the Calif. emissions are tough, lower fuel consumption for lower emissions, and different exhaust temperatures to go along with it. Also I forgot to mention about the alleged 4 sensors in the scan tool diagnosis. The scan tool shows 4 sensors still, but each bank mirrors a sensor. So instead of 4 sensors fluctuating independently, 2 sensors fluctuate simutaniously and the other 2 fluctuate simutaniously. Something like 450 millivolts on one bank, and something similiar on the other. Does this lead to any further answers?
You have just stated both “each bank mirrors a sensor” which sounded pretty good but then stated what reads like your truck has 4. It appears they are fooling the PCM into believing a sensor exists but how are they fooling the PCM into believing all is well when the signals are of the same frequency and amplitude (which they are not on a properly operating 4 sensor system?)
I’m not buying the extra 80 HP deal. Traditionally GM’ Heavy Duty engine variants have had slightly less power than the engines found in the under 8500 lb GVWR models. http://www.carsdirect.com/1996/chevrolet/k2500/specs vs. http://www.carsdirect.com/1996/chevrolet/k1500/specs
IIRC the 496 had 340 HP in the 2500-up Silverados. I never head of a 420HP variant being offered from the factory. A different ECM tune will not result in an extra 80 HP in N/A gas engine.
Well, per both dealerships(I have gone to 2 now) said that this ECM shows 4 sensors. But looking at the exhaust system, there are obviously 2. Now someone smarter than me designed this system and has got it to work. I do not know how, hence the reason I am on this site looking for help. If you want to come look at this vehicle, you are more than welcome to. I may even travel with it, like a travelling show, if that is what it takes to find all the answers. Because this emissions system stuff, like computers and millivolts are beyond my knowledge thresh hold. If a Chevy/GM dealer is telling me this, I can only believe them.
I am glad you got it straightened out. Sounds like a workhorse truck.
If you tampered with it, I.E. Removed the post Cat sensors, wouldn’t you have a check engine light. I would imagine your truck is rare, I didn’t know you could get a 2500 4x4 8.1L 6 speed. I will bet only a handfull were made. Sounds like GM made a truck that legally shouldn’t have been made and now they are pawning it off on you. I mean really… You removed 2 O2 sensors, put on a pipe with no spot for them and recalibrated the Pcm, hence no Check engine light…
These tables should help confuse you more. They are compilations, by the EPA, on vehicle categories, and emission programs for the past 15-20 years.
According to one table, 2003 model year was the last year for Tier 1. From the table, is your truck a HLDT (Heavy Light Duty Truck); or, something else? Maybe, your truck is, actually, a 2003MY carried to 2005MY? Such carry-overs are not unprecedented. Is there the mandatory label in the engine compartment for emissions certifications? And, does it say what year, and what category, the emissions standard cover?
http://www.epa.gov/greenvehicles/detailedchart.pdf
The truck was special order, and because it is special order, did not have the California emissions option included. This is legal, but can not ever register in California. The current exhaust has 2 ports after the cat. converters, but were plugged off with “GM” pipe plugs. As for the PCM, yes, that is odd. But both dealerships that I have gone to, have said that they have not seen the PCM set up before to “mirror” 2 sensors with 2 existing sensors. Oldschool said the same thing to me. That is why I furnished the software versions to him a couple of dyas ago.
The California emissions package is only required if the truck was sold in California. You could still register it there.
There is a mandatory label under the hood. But there is no “family” code or any number like that. Per the EPA chart paper work, my truck(9200lb. GVWR) would qualify as Medium Duty Passenger Vehicle(?). The info on the sticker under the hood says gasoline fueled heavy duty vehicle.
OK then. What would prevent someone from opening a PO Box in Utah or Oregon, order their vehicle in another state, buy in another state, then operate it in California? It would seem (maybe I’m not that smart, I don’t know) that California wold have safe gaurds to prevent someone from circumventing the CARB rules.
You held the camera too close to the object. A downloaded, enlarged, blur is still a blur.
I saw that classification of a MDPV. You know bureaucrats, if it’s a vehicle, it must carry people (in their minds).
The EPA doesn’t tell the auto makers HOW to design vehicles to meet the emission standard. It just tells car makers what the emission standards are. The problem with your truck is determining what the category it fits into, AND, making it Official.
On a side note, I didn’t know that it was still possible to get a manual trans. in 2005. I’ve always preferred manuals, and have never owned an automatic. I’m pretty saddened by the obvious reality that stick shift is going away (does anyone still sell a full size pickup with a manual?).
A 4x4 with a big block and a 6 speed manual? If this were my truck, I’d hang on to it for the rest of time.
That’s what I plan to do. Hold on to it for a long time, unless issues outside of my control dictate otherwise. Like dealerships & cust. service that do not know what they are doing.
That would work if you had an address to register the vehicle to in another state. Then you could register it in California after you got your plate at the other address.
I used to live in CA. I know you can register your car if you move in from out of state with an out of state car. It then only has to meet federal emission requirements to pass inspection.