Emissions Test

[ehjorten]

Okay...so I need to go get my 1991 V3500 emissions tested in Washington State to get the title transfer.  Only 5 years left till it is exempt.  I was hoping to put it off a little longer until I had to renew the tabs, but apparently in Washington you have to get an emissions test with all title transfers.  I have never dealt with this since the '91 is my newest vehicle.

The truck doesn't have CATs anymore cause the guy I bought it from has the luxury of registering his vehicles at his shop where, in that area, emissions tests aren't required.  First I will say that, I knew this before I bought it, just wasn't planning on having to deal with it this soon.  I have never had to do any emissions testing in my life except for once when the wife's 2003 got old enough to require it.  So...I don't have much experience in these matters.

My question is: What would you do?

Apparently if I don't pass (Washington does not have an underhood inspection, but I'm not counting on them blindly doing the sniff-test) I can spend $150 at a certified shop and then go back and get a waiver if I don't pass the second time.

I am planning on making sure there are no codes stored in the computer, changing spark plugs, changing fuel filter, changing oil, changing air-cleaner and then getting her good and hot before going to the test station.  I have to pass an Acceleration Simulation Mode (ASM) where they set the dyno load = [vehicle weight + 300 lbs]/300, gear selector in drive (not overdrive), speed at 25 mph.  Sniff-test must be < 1.5% CO & < 200 ppm HC

Other things I am contemplating...denatured alcohol in the tank with 1/4 tank of fuel.  I have read on other sites where this has actually worked for guys in Washington and they have posted the test results.

Finally...maybe I just go (possibly fail), go get $150 of work at a certified shop and then go back and get the waiver.  Only have to do this three times until it is exempt.  That is $450 over 5 years.

[topp]

3500 series vehicles are Heavy Duty and should be exempt from emissions to begin with....

[fitz]

Keep in mind that while people on this forum are trying to help you, these rules/regulations vary from state to state and county to county.

[ehjorten]

Unfortunately in Washington State there aren't exemptions per say.  For my OBDI there are two tests.  The ASM test (mentioned above) on a dyno for FWD and RWD (not full-time 4WD or AWD...they don't have double roller dynos at the test facilities), and the Two Speed Idle (TSI) test.  For vehicles 8,500 and over GVW or AWD you get the TSI.  For under 8,500 GVW you get the ASM.

[topp]

Interesting.
As far as I knew, it was the EPA that let the heavy duty trucks not require emissions....

[ehjorten]

So I was a bit mistaken...WA goes by GVWR not GVW.  I wasn't sure.  So to my understanding the GVW of my truck is about 5,100 lbs.  The GVWR is 9,000; so that puts me into the TSI test which is 3.0% CO and 400 ppm HC at idle and 2,500 RPM.

To some extent individual states are allowed to make more restrictive rules than the Fed.  But as I remember it is not suppose to make undue difficulty on manufacturers to keep up with and market to wildly different state laws.  This has been getting more and more muttled with all of California's B.S.

[ehjorten]

Checked the codes tonight and the periodic 'Service Engine Soon' is a code 44 or lean exhaust condition.  So...now to check fuel pressure and for vacuum leaks.  Not completely sure of the history of this truck and I have only had it since the second week of December.  Probably going to reset it tonight and then drive it around a bit to see if it comes back.  It hasn't come back in a while so maybe me 'blowin the carbon out of it on the highway worked out the kinks?!

[ehjorten]

Failed emissions test on Friday.  Two Speed Idle Test only (Idle and 2,500 RPM - CO <= 3.0%, HC <= 400 PPM).  I got Idle = 6.64% CO, 355 PPM HC.  2,500 RPM = 8.65% CO, 689 PPM HC.

So this weekend I found a significant vacuum leak and fixed that, put a new O2 sensor in, new spark plugs (all looked real good except for #8 looked fuel fouled - still need to determine why), put a new coolant temperature sensor in cause it just looked crusty and nasty (only $12 to do so), put a new 195° thermostat in cause the previous owner put a 180° one in (195° is stock and will help with emissions), replaced some crusty looking vacuum hoses, and finally got the oil changed.  I still need to change the fuel filter and check the fuel pressure.

I haven't tested the O2 sensor or the coolant temp sensor to see if they were bad (O2 sensor was probably the OE one anyways).  Any guys out there qualified to say if that is enough to get my CO and HC down?  I am thinking that the large vacuum leak (port from TB to charcoal cannister - vacuum only off idle) might solve my 2,500 RPM issue, but not sure about idle.  My wife says just go re-test and see without spending the requisite $150 at an AES certified shop.  If I fail then I'm only out $15, but if I pass then I saved at least $150.  I'm running out of time to get the title transferred.

[VileZambonie]

I would need more data to tell you why the CO and HC's were high. Did the report tell you what the O2 levels were as well? If you did everything you said correctly and set the timing go in for the retest.

[ehjorten]

The emissions report said:

Idle: HC = 355 ppm, CO = 6.94%, CO+O2 = 12.64%, O2 = 6.87%
2,500 RPM: HC = 689 ppm, CO = 8.65%, CO+O2 = 12.15%, O2 = 8.54%

Limits: HC 400 ppm, CO 3.0%

I did not reset the timing however...what should the timing be set to for this engine?

By the way...I went in to talk to a local AES certified shop which happens to be a Chevy Dealership and they were completely un-helpful!!!  Why should I have to spend money at a certified shop if I know what I am doing and the certified shop is incompetent?!

I'm still waiting on my 1991 R/V service manual and wiring diagram books to arrive!  I love having all of that stuff!!  I have Parts and Illustration Catalogs, Factory Service Manuals and Wiring Diagrams for both my Chevelle and '77 K20.  I also have the Fisher Body Manual for the Chevelle.  They are invaluable resources!!!

[TexasRed]

If #8 is not burning the fuel, it'll just read really high HCs. You might try new cap and rotor too.

[zieg85]

I bought a pair of 3" 50 state legal replacement Catalytic converters from a vendor on eBay for $80 that I was going to put on my 86 right after the headers.  You might want to do it right.  In Indiana they inspect the exhaust system with a mirror to assure cats are on and there are no holes in the mufflers...

[VileZambonie]

Idle: HC = 355 ppm, CO = 6.94%, CO+O2 = 12.64%, O2 = 6.87%
2,500 RPM: HC = 689 ppm, CO = 8.65%, CO+O2 = 12.15%, O2 = 8.54%

HC's are too high (Non combusted fuel)
CO2 is low (ineeficient combustion)
CO and O2 are high
Because there is so much oxygen in the exhaust you either have a bad vacuum leak or a cylinder misfire.

[ehjorten]

Who needs CATs?!  Or denatured alcohol?
Passed with flying colors!



First test before I fixed the vacuum leak, replaced all of the crusty vacuum lines, replaced the plugs and put a new O2 sensor in.

[Jim Rockford]

change your oil just before you go in.