Failed smog on 1988 with 350 TBI

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Frankenchevy

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And it could have been. I used to do those alot in the 80's. My race buddies would come to the station I worked at. I'd pull up a car I had in there for a tune up that I knew would pass and plug in their #'s. Happened all the time. I'm rusty on that **** now for sure, but I do remember an engine misfire will cause HI HC, so if your HC is good, then all your plugs, wires, cap, rotor all that is still good. No misfires, unless you're getting a lean misfire which IS NOT your case since it's HI CO which is in most cases, Rich AF mixture. How does your spray pattern look on the injectors? Do you know if it failed, Idle or high rpm or both??
Iirc it was high rpm. He didn’t log it, so I didn’t get a printout. I just remember the 1.6% CO at 2500rpm was the problem.

Failing here escalates things quickly, so he’s basically hooking me up to the sniffer to help me get it figured out before the actual test. No dyno, just two speed (idle and 2500rpm).
 

DoubleDingo

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Iirc it was high rpm. He didn’t log it, so I didn’t get a printout. I just remember the 1.6% CO at 2500rpm was the problem.

Failing here escalates things quickly, so he’s basically hooking me up to the sniffer to help me get it figured out before the actual test. No dyno, just two speed (idle and 2500rpm).
Once you get it to pass, now that it has failed, you'll get to do it again next year because it will have nice a fat GROSS POLLUTER notation associated with the VIN. We all know it, but the elites won't do it, these vehicles should not be required to do bi-annual emissions testing because they are not driven high miles and are much fewer on the road.

It's good that the shop is working with you to pin-point the problem. Some just send you on your way with a referral to this shop or that to get it fixed there.
 

Frankenchevy

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Remember that MAP reports out absolute pressure, not gauge pressure. So subtract the MAP reading from atmospheric and that is gauge pressure (engine vacuum).
Got it, it appears I was doing bad math and my vacuum is actually quite good then…

Vacuum (inHg) = 30 − (MAP in kPa × 0.3)

= 30 − (26.2 × 0.3)
= 30 − 7.86
= 22.14 inHg


Once you get it to pass, now that it has failed, you'll get to do it again next year because it will have nice a fat GROSS POLLUTER notation associated with the VIN. We all know it, but the elites won't do it, these vehicles should not be required to do bi-annual emissions testing because they are not driven high miles and are much fewer on the road.

It's good that the shop is working with you to pin-point the problem. Some just send you on your way with a referral to this shop or that to get it fixed there.
Yes, but he saved me the trouble of it being labeled a gross polluter. Officially, I did not fail. He didn’t even charge me. He’s a good guy.
 

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Got it, it appears I was doing bad math and my vacuum is actually quite good then…

Yes, but he saved me the trouble of it being labeled a gross polluter. Officially, I did not fail. He didn’t even charge me. He’s a good guy.
That's a good shop, good man, you're lucky he did that. I would recommend what was already mentioned, and that is running some cleaner through it and get some highway miles under its belt before the next check. If it legitimately passed for you to buy it, it could simply be it needs to be blown out some to clean the carbon off the pistons.
 

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if this is california,...the Leno Law = still a unsurpassed Bill.
(...Leno Bill, one of the things I have seen on it concerns those vehicles that are more than 35 plus years old....so a 1988 is now 38 years old,...)

I really wonder how many classic cars leave California, due to this. I live in NYS and after 25 years, no more plugging in ,..just a visual safety inspection for lights / brakes/ frame etc. ...= frame to make sure the rust has not transformed it into thin clean air....and anything older than 25 years is not driven much. Rare to see something out from Nov to April, ... maybe a working truck cobbled together from many and being saved by fluid film. (like something imported from somewhere warm and dry without salt).

 
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Frankenchevy

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if this is california,...the Leno Law = still a unsurpassed Bill.
(...Leno Bill, one of the things I have seen on it concerns those vehicles that are more than 35 plus years old....so a 1988 is now 38 years old,...)

I really wonder how many classic cars leave California, due to this. I live in NYS and after 25 years, no more plugging in ,..just a visual safety inspection for lights / brakes/ frame etc. ...= frame to make sure the rust has not transformed it into thin clean air....and anything older than 25 years is not driven much. Rare to see something out from Nov to April, ... maybe a working truck cobbled together from many and being saved by fluid film. (like something imported from somewhere warm and dry without salt).

Unfortunately, Leno’s law won’t apply to 1988s. The rolling cutoff will stop at 1986.
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goldpack

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so,...what you need is a clean title off 73-1986, with a clean vin plate that matches.;)
old carb dead ones, springing back to life with fuel injection and trim pieces of 87-88
 

Frankenchevy

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so,...what you need is a clean title off 73-1986, with a clean vin plate that matches.;)
old carb dead ones, springing back to life with fuel injection and trim pieces of 87-88
I’m currently looking for a property/cabin in a smog exempt county of CA somewhere off of 395, preferably as far north as possible so it’s halfway between our house and my in-laws in Oregon.
 

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No emissions testing here in FL. My 87 has emissions and catalytic removed. The exhaust smells really bad though I almost want to put the emissions back on- smog tees, air pump ad have to get a catalytic converter.
 

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No emissions testing here in FL. My 87 has emissions and catalytic removed. The exhaust smells really bad though I almost want to put the emissions back on- smog tees, air pump ad have to get a catalytic converter.
someone with better ideas may say something,...
I wonder if bigger newer things like cats made for a 1990s 454, or the mighty 8.1 etc. would gobble up the stink
. (just with more cat material).
 

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someone with better ideas may say something,...
I wonder if bigger newer things like cats made for a 1990s 454, or the mighty 8.1 etc. would gobble up the stink
. (just with more cat material).
In CA the cats have to be a match to the vehicle.
 

goldpack

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In CA the cats have to be a match to the vehicle.
well, in a state and locality that no one is looking, or actually looking,

and the member I was replying to was in Florida,...and just looking to not stink the neighborhood with fumes.
 

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@Frankenchevy

in your local reads in california, does anyone run more alcohol or with any gas additive to try to get a pass after they had a minor failure like yours,..

.just wondering if you see anything locally published. like converting a antique to be able to run on some higher level of alcohol to pass a test,...even if not running around on it at all for the rest of the year.

I started this thread recently,...not sure how much or how many parts someone would have to swap on to make for a stable build in a 1988 EFI

 

Bextreme04

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@Frankenchevy

in your local reads in california, does anyone run more alcohol or with any gas additive to try to get a pass after they had a minor failure like yours,..

.just wondering if you see anything locally published. like converting a antique to be able to run on some higher level of alcohol to pass a test,...even if not running around on it at all for the rest of the year.

I started this thread recently,...not sure how much or how many parts someone would have to swap on to make for a stable build in a 1988 EFI

Unfortunately you have to swap the entirety of the emissions controls from whatever it is. So he would likely have to swap in a flex fuel system from a 2004 or later equivalent Tahoe/Burb. That would probably require engine/trans/fuel line and tank mods/entire exhaust from manifolds to cats from the swap vehicle. Then you have to have the VIN from the swap vehicle and take the whole thing to a SMOG referee to have it signed off.
 

Frankenchevy

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@Frankenchevy

in your local reads in california, does anyone run more alcohol or with any gas additive to try to get a pass after they had a minor failure like yours,..

.just wondering if you see anything locally published. like converting a antique to be able to run on some higher level of alcohol to pass a test,...even if not running around on it at all for the rest of the year.

I started this thread recently,...not sure how much or how many parts someone would have to swap on to make for a stable build in a 1988 EFI

Smog testing is only applicable to 1976 and newer vehicles, so I’m not so sure about antiques. Though, I do have to keep in mind that in other parts of the country that something from 1976 surviving the rust is an antique.

I did ask the Internet if a higher ethanol content reduces CO percentage, and it confirmed that it does in fact result in lower carbon monoxide. Though, I asked a follow up question and it gave me an incorrect response on some basic math, so I’m not so sure how much I trust the question I previously posed about carbon monoxide. Honestly, it’s been a long time since I had chemistry so I would have to think about that for a little while, but it sounds correct.

The follow up question was due to the fact that we do not have E 20 blends available at the pump. There are however, a few gas stations about an hour away that have E 85. I could theoretically put 6 1/2 gallons of E 10 to every 1 gallon of E 85 to achieve an E20 blend.

The first time asking it lied and tried to trick me into using E47.5.
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Always question AI people!
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Quite possible, and this is the part that I’m not sure on at all, and therefore would not roll the dice on my next inspection, I am not sure that the rudimentary TBI computer would react appropriately to a higher ethanol blend.
 

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