Help with Smog failure

[PlayingWithTBI]

This vehicle doesn't self-test the Evap system. HOW are they testing it?

No, it doesn't even have an evap valve. The CC is plumbed direct to the TB. IIRC (it's been 13 years since I lived in CA) they put another cap on the gas tank which pressurizes the tank and measures rate of pressure loss. I've had to replace my fuel cap one time, then another time smoke test for a bad vacuum line going to the CC/TB. The line going from the tank to the CC was the culprit.

Believe they clamp the hose from the carbon canister to the gas tank then pressurize the tank via a gas cap adapter.

Maybe, I don't remember them clamping the line though.

 

[89obsSB]

They did away with emission checks in Ohio long before I got my license. Never had to deal with it myself. I would suggest moving to a state without emissions checks lol. I’m just kidding but sounds like a easier route.

 

[PlayingWithTBI]

Oh yeah, and they take your gas cap, put it on a tool and pump it up to ensure it seals properly.

I would suggest moving to a state without emissions checks lol. I’m just kidding but sounds like a easier route.

I got my truck "Historic" plates and exempt from emissions here in Maricopa County AZ

 

[89obsSB]

Oh yeah, and they take your gas cap, put it on a tool and pump it up to ensure it seals properly.


I got my truck "Historic" plates and exempt from emissions here in Maricopa County AZ

Yea we have a cap tester at work. Are all states like that as long as you have historic plates?

 

[Nad_Yvalhosert]

Premium burns cleanest. Slower, longer burn.

Not true. All grades of gasoline burn at the same speed. The octanes just keep it from premature ignition, based on compression level, or a hot spot.

 

[L31MaxExpress]

Not true. All grades of gasoline burn at the same speed. The octanes just keep it from premature ignition, based on compression level, or a hot spot.

If that was the case you would not see low compression engines that are not knock limited in terms of timing, dyno higher numbers on 87 octane than 91.

 

[Schurkey]

If that was the case you would not see low compression engines that are not knock limited in terms of timing, dyno higher numbers on 87 octane than 91.

Far as I know, that's more a case of lower-octane-rated fuel having more BTUs per gallon than higher-octane-rated fuel, has nothing to do with burn speed/flame travel.

Burn speed/flame travel has a LOT to do with in-cylinder turbulence, little or nothing to do with octane rating.

 

[L31MaxExpress]

Far as I know, that's more a case of lower-octane-rated fuel having more BTUs per gallon than higher-octane-rated fuel, has nothing to do with burn speed/flame travel.

Burn speed/flame travel has a LOT to do with in-cylinder turbulence, little or nothing to do with octane rating.

Regardless of why, premium fuel generally combusts more controllably without detonation which results in cleaner emissions. I hear alot of SBC engines pinging at part throttle on 87.

 

[E-gads]

This conversation reminded me of years ago when I owned an '85 S10 Blazer with a 2.5L four cylinder engine. I couldn't get it to pass emissions here in Oregon at idle. At the time they checked emissions at idle and at 2500 RPM. I was fine at 2500 but not at idle. Couldn't for the life of me figure out why. So I put a paper clip in the ALDL connector shorting the diagnostic terminal to ground (A to B). It ran like crap but for some reason it passed emissions. First couple of times I had a string on it so I could covertly pull out the paper clip after they checked idle but I forgot to pull it out one time and it still passed. Did that for several years and it never failed. Well, I guess it failed when a connecting rod blew through the side of the block but that's another story.

Not suggesting you try that by the way.

 

[GoToGuy]

If that was the case you would not see low compression engines that are not knock limited in terms of timing, dyno higher numbers on 87 octane than 91.

I don't know what conditions your low comp' dyno engine runs. Yeah through some great engineering we now have amazing power plants 30 years ago couldn't imagine. Octane is measurement of resistence to preignition. "Octane's" are not a physical thing or object. Think temp scale. Can you see 80 degrees F or 15 C ? The Germans (?) figured out how to add lead to gasoline to increase the resistence to preignition. Allowing Higher compression ratio and timing. Later 60s and 70s factory supercars must use premium or super because of 10 to 1, 11 to 1, 12 to 1 compression ratios. Purple colored dyed AVGas rated at 115/145. High compression engines.