Arizona Emissions - The 1947 - Present Chevrolet & GMC Truck Message Board Network

jor · 08-10-2009, 01:13 PM

87 Suburban 5.7L, TBI

Just looking for a little help getting my burb through Tucson emissions. It has passed before but this year has failed twice with High loaded HC and high idle CO. After it failed the first time I gave it a quick tune up (plugs, PCV, oil & filter, air filter), Seafoam directly into the intake and a gallon of denatured alcohol in the gas tank. I'm trying to get it through emissions so I can give it to my daughter. Thanks.
jor

LOADED HC PPM: 195 (100 is passing)
CO IDLE %: 1.56 (1.2 is passing)

Orange77 · 08-10-2009, 02:24 PM

did you run it through emissions after you did all that to it? i had a similar problem when i went to emissions all i did was add an octane booster in the tank and tuned the carb a lil better but seein as you have TBI im not sure how youd go about that. my cousin had a problem with his 82 stepside and my uncle told him to add alcohol to the tank too and he passed

tomtuna1978 · 08-10-2009, 02:48 PM

dose the check engine light come on? you might have a code for a o2 sensor or somthing else. id check the codes, and maybe check the cataliac converter for rattling or coming apart,might need a new cat. .... just my 2 cents

jor · 08-10-2009, 09:15 PM

Yea, after it failed the first time I did all that and it failed again. No check engine light and the cat seems fine. I replaced the O2 sensor last year. I have an old F-100 which of course is carburated. No problem with that one as I just lean it out, retard the timing and add some alcohol but with the TBI, I'm not sure what to do beyond what I have already. Not sure what the octane booster would do. I was thinking of cruising the auto stores looking for additives. One thing I forgot to mention. This 5.7L has bad valve guide seals and smokes at idle sometimes. I put new seals in last year (both umbrella and the other) and it was great for a couple of months, then started up again. Grrrrr... Thanks.
jor

Orange77 · 08-11-2009, 01:16 AM

your probably still burning enough oil to mess up your emissions test and the octane booster burns the gas better like higher rated octane gas does. i think its the 104 octane booster that raises it 3 octane points so i put the highest rated gas at the pump and that to have "96" octane gas so that it burns better and more completely to lower the emissions. at least that works for me.

08-10-2009, 01:13 PM	#1
jor Registered User Join Date: Feb 2007 Location: Tucson Posts: 44	Arizona Emissions 87 Suburban 5.7L, TBI Just looking for a little help getting my burb through Tucson emissions. It has passed before but this year has failed twice with High loaded HC and high idle CO. After it failed the first time I gave it a quick tune up (plugs, PCV, oil & filter, air filter), Seafoam directly into the intake and a gallon of denatured alcohol in the gas tank. I'm trying to get it through emissions so I can give it to my daughter. Thanks. jor LOADED HC PPM: 195 (100 is passing) CO IDLE %: 1.56 (1.2 is passing)

08-10-2009, 02:24 PM	#2
Orange77 Registered User Join Date: Apr 2009 Location: Tucson, AZ Posts: 184	Re: Arizona Emissions did you run it through emissions after you did all that to it? i had a similar problem when i went to emissions all i did was add an octane booster in the tank and tuned the carb a lil better but seein as you have TBI im not sure how youd go about that. my cousin had a problem with his 82 stepside and my uncle told him to add alcohol to the tank too and he passed

08-10-2009, 02:48 PM	#3
tomtuna1978 Registered User Join Date: Apr 2009 Location: Bend,Oregon Posts: 225	Re: Arizona Emissions dose the check engine light come on? you might have a code for a o2 sensor or somthing else. id check the codes, and maybe check the cataliac converter for rattling or coming apart,might need a new cat. .... just my 2 cents

08-10-2009, 09:15 PM	#4
jor Registered User Join Date: Feb 2007 Location: Tucson Posts: 44	Re: Arizona Emissions Yea, after it failed the first time I did all that and it failed again. No check engine light and the cat seems fine. I replaced the O2 sensor last year. I have an old F-100 which of course is carburated. No problem with that one as I just lean it out, retard the timing and add some alcohol but with the TBI, I'm not sure what to do beyond what I have already. Not sure what the octane booster would do. I was thinking of cruising the auto stores looking for additives. One thing I forgot to mention. This 5.7L has bad valve guide seals and smokes at idle sometimes. I put new seals in last year (both umbrella and the other) and it was great for a couple of months, then started up again. Grrrrr... Thanks. jor Last edited by jor; 08-10-2009 at 09:34 PM.

08-11-2009, 01:16 AM	#5
Orange77 Registered User Join Date: Apr 2009 Location: Tucson, AZ Posts: 184	Re: Arizona Emissions your probably still burning enough oil to mess up your emissions test and the octane booster burns the gas better like higher rated octane gas does. i think its the 104 octane booster that raises it 3 octane points so i put the highest rated gas at the pump and that to have "96" octane gas so that it burns better and more completely to lower the emissions. at least that works for me.



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