Passing Smog "Trick"
11-24-09, 09:54 AM
#27
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Perhaps the dates on each post should be more noticeable. There have been a few times that I have almost posted on old threads and just happened to catch the date and stopped myself. Of course there were a few times that I didn't catch it, and thus I became the jackass.
09-24-12, 02:18 PM
#32
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so have 100% E85 in the tank when being tested or a mix w/regular fuel?
09-24-12, 03:35 PM
#33
It's easy to make a first gen pass.
It's easy to make a first gen pass.
Always be cool to the smog guy. Be a dick and see how far that gets you.
1) Ensure the timing is perfect, they'll fail you for this.
2) If it's an '84 or '85, you can safely assume that the two precats have disintegrated and the pieces are now clogging third one.
3) Remove the last cat and the first one connected to the exhaust manifold. If they are good, don't mess with them, as long as thing are set up right and all three are good, you should pass.
4) Assuming the first precat is hollow or full of crumbled parts as well as a screen I seem to recall. You need to make sure the first two pre cats are completely hollow.
5) Buy a '90-'92 rear cat, I believe it's a three way. Unfortunately, the studs on the new converter are wider that the ones on the pipes so out with a sawzall and elnogate the holes on the flanges that the big cat goes to. Mount the cat, hook up the actuator pipe (I've never understood why a '90 cat has this as I thought the secondary ports were electric.)
6) Warm up the engine, don't let it sit at the smog yard and cool down. It will pass but I'm willing to bet the smog guy says you need a new gascap and as soon as you get one, you pass.
Always be cool to the smog guy. Be a dick and see how far that gets you.
1) Ensure the timing is perfect, they'll fail you for this.
2) If it's an '84 or '85, you can safely assume that the two precats have disintegrated and the pieces are now clogging third one.
3) Remove the last cat and the first one connected to the exhaust manifold. If they are good, don't mess with them, as long as thing are set up right and all three are good, you should pass.
4) Assuming the first precat is hollow or full of crumbled parts as well as a screen I seem to recall. You need to make sure the first two pre cats are completely hollow.
5) Buy a '90-'92 rear cat, I believe it's a three way. Unfortunately, the studs on the new converter are wider that the ones on the pipes so out with a sawzall and elnogate the holes on the flanges that the big cat goes to. Mount the cat, hook up the actuator pipe (I've never understood why a '90 cat has this as I thought the secondary ports were electric.)
6) Warm up the engine, don't let it sit at the smog yard and cool down. It will pass but I'm willing to bet the smog guy says you need a new gascap and as soon as you get one, you pass.
09-24-12, 04:22 PM
#35
It's easy to make a first gen pass.
Always be cool to the smog guy. Be a dick and see how far that gets you.
1) Ensure the timing is perfect, they'll fail you for this.
2) If it's an '84 or '85, you can safely assume that the two precats have disintegrated and the pieces are now clogging third one.
3) Remove the last cat and the first one connected to the exhaust manifold. If they are good, don't mess with them, as long as thing are set up right and all three are good, you should pass.
4) Assuming the first precat is hollow or full of crumbled parts as well as a screen I seem to recall. You need to make sure the first two pre cats are completely hollow.
5) Buy a '90-'92 rear cat, I believe it's a three way. Unfortunately, the studs on the new converter are wider that the ones on the pipes so out with a sawzall and elnogate the holes on the flanges that the big cat goes to. Mount the cat, hook up the actuator pipe (I've never understood why a '90 cat has this as I thought the secondary ports were electric.)
6) Warm up the engine, don't let it sit at the smog yard and cool down. It will pass but I'm willing to bet the smog guy says you need a new gascap and as soon as you get one, you pass.
Always be cool to the smog guy. Be a dick and see how far that gets you.
1) Ensure the timing is perfect, they'll fail you for this.
2) If it's an '84 or '85, you can safely assume that the two precats have disintegrated and the pieces are now clogging third one.
3) Remove the last cat and the first one connected to the exhaust manifold. If they are good, don't mess with them, as long as thing are set up right and all three are good, you should pass.
4) Assuming the first precat is hollow or full of crumbled parts as well as a screen I seem to recall. You need to make sure the first two pre cats are completely hollow.
5) Buy a '90-'92 rear cat, I believe it's a three way. Unfortunately, the studs on the new converter are wider that the ones on the pipes so out with a sawzall and elnogate the holes on the flanges that the big cat goes to. Mount the cat, hook up the actuator pipe (I've never understood why a '90 cat has this as I thought the secondary ports were electric.)
6) Warm up the engine, don't let it sit at the smog yard and cool down. It will pass but I'm willing to bet the smog guy says you need a new gascap and as soon as you get one, you pass.
Besides which, unless you are lucky the vast majority of smog techs will not have any experience dealing with a first-gen, since there are so few left running in CA enhanced-smog areas. Goes double for SA's, which differ from FB's considerably in the emissions department.
1) Three of the last three smog places I have been to didn't even know how to hook up their timing sensing equipment to a first-gen properly, and NONE of them actually verified the timing with a timing light - - once they got a signal at idle, they just marked it 'passed.'
- One gave up and used the 2-ft wide inductive loop, which then proceeded to double-count since it was grabbing both leading and trailing impulses.
- Another insisted on hooking the clamp up to the top (trailing) plug regardless of my explanations, and then was mystified why the signal would go away whenever the engine was accelerating - - which means he'd never worked an 80 SA before. Trailing timing is suppressed for the first 130 seconds when accelerating between ~1100 and 3300 RPM on a Cali-spec 80 SA.
- Third guy looked at the two coils & the dizzy, scratched his head, and asked me if I knew how to hook it up.
None of them were able to identify the charcoal canister (inside the air cleaner lid on an SA) or the proper tank vent line to clamp to test the tank (even though I have mine colored red on purpose) either.
2) through 5) don't apply to SA's, as they have no cats.
To pass an SA you just have to make sure all your emissions parts (thermal reactor, air duct, air routing pipes, heat exchanger, ACV, vent valve, richer, coasting valve, solenoids, the whole works) are working right. And then you pray.
6) doubly true on an SA, and hard to do when the tech doesn't know his way around under the hood and spends 45 minutes trying to decipher the vacuum routing sticker, while the car sits and cools. The decent ones will let you re-warm the car (minimum 3 minutes at over 2000rpm) before running the actual test.
And for the privilege of having to teach these gents their jobs each of the last three times I've tested, I get to pay out a fat slice of jack... and still risk getting downchecked if anything does not go perfect.
So no, I'm afraid I wouldn't call passing a first-gen "easy."
09-24-12, 05:50 PM
#36
What's that smell?
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This is one thing that makes me happy about being in cold, miserable UK-pre 86 rotories emissions exempt so my old girl can sit at the test station chugging away premixed up and no questions.
09-25-12, 02:31 AM
#37
I was somewhat surprised to see this old thread come back alive, but I guess it's a topic that we come back to time and time again.
I just had my '85 smog checked this month, and my mechanic told me that his guy will blow air into the tail pipe while doing the test. idk, I wasn't there. All I know is that I got passed and I'm on the road, even though my ACV wasn't workingand the first cat was hollow. With the headers now installed, I'm not looking back. If it doesn't get registered again, it will be a dedicated track car.
However, I may play around with the exhaust and switch out the presilencer for a high-flow cat since my daughters have asked me if there was a way to make the car not stink so bad.
On the smog test papers I noticed that it showed that here in California, rotaries are categorized under the gross-polluter profile.
I just had my '85 smog checked this month, and my mechanic told me that his guy will blow air into the tail pipe while doing the test. idk, I wasn't there. All I know is that I got passed and I'm on the road, even though my ACV wasn't workingand the first cat was hollow. With the headers now installed, I'm not looking back. If it doesn't get registered again, it will be a dedicated track car.
However, I may play around with the exhaust and switch out the presilencer for a high-flow cat since my daughters have asked me if there was a way to make the car not stink so bad.
On the smog test papers I noticed that it showed that here in California, rotaries are categorized under the gross-polluter profile.
09-25-12, 10:04 AM
#38
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It's easy to make a first gen pass.
Always be cool to the smog guy. Be a dick and see how far that gets you.
1) Ensure the timing is perfect, they'll fail you for this.
2) If it's an '84 or '85, you can safely assume that the two precats have disintegrated and the pieces are now clogging third one.
3) Remove the last cat and the first one connected to the exhaust manifold. If they are good, don't mess with them, as long as thing are set up right and all three are good, you should pass.
4) Assuming the first precat is hollow or full of crumbled parts as well as a screen I seem to recall. You need to make sure the first two pre cats are completely hollow.
5) Buy a '90-'92 rear cat, I believe it's a three way. Unfortunately, the studs on the new converter are wider that the ones on the pipes so out with a sawzall and elnogate the holes on the flanges that the big cat goes to. Mount the cat, hook up the actuator pipe (I've never understood why a '90 cat has this as I thought the secondary ports were electric.)
6) Warm up the engine, don't let it sit at the smog yard and cool down. It will pass but I'm willing to bet the smog guy says you need a new gascap and as soon as you get one, you pass.
Always be cool to the smog guy. Be a dick and see how far that gets you.
1) Ensure the timing is perfect, they'll fail you for this.
2) If it's an '84 or '85, you can safely assume that the two precats have disintegrated and the pieces are now clogging third one.
3) Remove the last cat and the first one connected to the exhaust manifold. If they are good, don't mess with them, as long as thing are set up right and all three are good, you should pass.
4) Assuming the first precat is hollow or full of crumbled parts as well as a screen I seem to recall. You need to make sure the first two pre cats are completely hollow.
5) Buy a '90-'92 rear cat, I believe it's a three way. Unfortunately, the studs on the new converter are wider that the ones on the pipes so out with a sawzall and elnogate the holes on the flanges that the big cat goes to. Mount the cat, hook up the actuator pipe (I've never understood why a '90 cat has this as I thought the secondary ports were electric.)
6) Warm up the engine, don't let it sit at the smog yard and cool down. It will pass but I'm willing to bet the smog guy says you need a new gascap and as soon as you get one, you pass.
2-4 is correct, the precat is hollow, except on a turbo, and then its clogged. they make almost no difference in emissions when the car is warmed up.
5. no need, you can just run the stock cat if its good. the air tube is for the air pump air under some conditions, its actually not used during the smog test.
6. right! leave it running. the cat needs to be a certain temp to work (~600C), and the THERMAL reactor definitely needs heat.
7. you MUST check the air control valve, it MUST work, or you will not pass, ever.
09-26-12, 09:21 AM
#39
Too funny
I've had SAs pass the first time easily. Carb has to be perfectly set, timing set and the thermal reactor works a little better when it's not rusted through.
Funny about the timing. Imagine the look on the smog guy's face if you've gone with the DLIDFIS route? And you're dist is missing three HTLs?
I agree with your sentiment 100% about being a dick. I know people (not friends) who like to treat people like crap. They do this in restaurants too heh heh. Then they complain about lousy service and they're too clueless to realize that maybe, just maybe, the reason they have problems with everyone is everyone else, it's them.
Funny about the timing. Imagine the look on the smog guy's face if you've gone with the DLIDFIS route? And you're dist is missing three HTLs?
I agree with your sentiment 100% about being a dick. I know people (not friends) who like to treat people like crap. They do this in restaurants too heh heh. Then they complain about lousy service and they're too clueless to realize that maybe, just maybe, the reason they have problems with everyone is everyone else, it's them.
09-26-12, 09:34 AM
#40
Comments.
1. its been a really long time since anyone has checked the timing. i go to the same guy every time, and he knows where to put the light, but doesn't go further. that being said i've smogged cars with advanced timing and stock timing and the timing influences NOX, but has a really teeny effect on anything else.
2-4 is correct, the precat is hollow, except on a turbo, and then its clogged. they make almost no difference in emissions when the car is warmed up.
5. no need, you can just run the stock cat if its good. the air tube is for the air pump air under some conditions, its actually not used during the smog test.
6. right! leave it running. the cat needs to be a certain temp to work (~600C), and the THERMAL reactor definitely needs heat.
7. you MUST check the air control valve, it MUST work, or you will not pass, ever.
2-4 is correct, the precat is hollow, except on a turbo, and then its clogged. they make almost no difference in emissions when the car is warmed up.
5. no need, you can just run the stock cat if its good. the air tube is for the air pump air under some conditions, its actually not used during the smog test.
6. right! leave it running. the cat needs to be a certain temp to work (~600C), and the THERMAL reactor definitely needs heat.
7. you MUST check the air control valve, it MUST work, or you will not pass, ever.
2) You're right, they're basically there to get the car to pass the cold start emission standard. Are you saying the first pre-cat is hollow from the factory? It wasn't on my '84 12a.
3) A friend owned a wrecking yard and they tried using the stock last cat only, wouldn't pass. Newer cat, passed easily, they did this for several cars too. (No they didn't try the stock cat first on the other but used the 90-92 one on the rest of the '84s & '85s they needed tested).
4) I don't understand point 5. I'm talking about the pipe that goes from the big cat to the secondary port actuators. Depending on how high they have to go on the test, the ports will open but I don't see that as a problem. Are you saying the air tube outlet on the 90-92 cats is for the air pump; that would certainly explain its existence.
5) #7 is spot on although I've never seen a failed one and have now jinxed myself.
09-26-12, 09:49 AM
#41
I have not ever seen a smog tech test my timing that I can recall, and I'm certain it was not done for any of my last three tests, the most recent of which was only 4 months ago.
Absent the use of a timing light, there is no other way to test engine timing on a distributor-equipped first-gen.
Maybe you mean they test for an ignition signal & idle rpm within a given range?
That's not testing timing, but it is essential to the machine's ability to test.
Or maybe they are supposed to, but simply don't bother.
09-26-12, 10:56 AM
#42
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1) In California, before the test begins, they will test the timing, if it's off, automatic fail.
2) You're right, they're basically there to get the car to pass the cold start emission standard. Are you saying the first pre-cat is hollow from the factory? It wasn't on my '84 12a.
3) A friend owned a wrecking yard and they tried using the stock last cat only, wouldn't pass. Newer cat, passed easily, they did this for several cars too. (No they didn't try the stock cat first on the other but used the 90-92 one on the rest of the '84s & '85s they needed tested).
4) I don't understand point 5. I'm talking about the pipe that goes from the big cat to the secondary port actuators. Depending on how high they have to go on the test, the ports will open but I don't see that as a problem. Are you saying the air tube outlet on the 90-92 cats is for the air pump; that would certainly explain its existence.
5) #7 is spot on although I've never seen a failed one and have now jinxed myself.
2) You're right, they're basically there to get the car to pass the cold start emission standard. Are you saying the first pre-cat is hollow from the factory? It wasn't on my '84 12a.
3) A friend owned a wrecking yard and they tried using the stock last cat only, wouldn't pass. Newer cat, passed easily, they did this for several cars too. (No they didn't try the stock cat first on the other but used the 90-92 one on the rest of the '84s & '85s they needed tested).
4) I don't understand point 5. I'm talking about the pipe that goes from the big cat to the secondary port actuators. Depending on how high they have to go on the test, the ports will open but I don't see that as a problem. Are you saying the air tube outlet on the 90-92 cats is for the air pump; that would certainly explain its existence.
5) #7 is spot on although I've never seen a failed one and have now jinxed myself.
2. no it had something in it from the factory, but the chances of something being there now are small. if there is, the cat was probably replaced.
3. if the stock cat is good, it'll pass.
4. that big pipe is for the "split air" from the ACV, as well as the 6 ports.
5. the ACV's usually do work, but you do have to check them pre test.
09-26-12, 09:52 PM
#43
Since we rotaries inject oil into the rotors with the OMP, doesn't that increase the amount of hydrocarbons we produce? I don't see other types on internal combustion engines which intentionally introduce oil to where it will be burned.
Burning oil makes hydrocarbons. But what if we used these new clean burning synthetics? They aren't supposed to produce hydrocarbons when burned. I know that the owners manual is against synthetic oils, but that was at a time when the early synthetics created problems for the seals, which isn't an issue now.
Just thinking that one of the reasons why rotary exhaust is so dirty is that we intentionally burn oil.
Burning oil makes hydrocarbons. But what if we used these new clean burning synthetics? They aren't supposed to produce hydrocarbons when burned. I know that the owners manual is against synthetic oils, but that was at a time when the early synthetics created problems for the seals, which isn't an issue now.
Just thinking that one of the reasons why rotary exhaust is so dirty is that we intentionally burn oil.
09-29-12, 01:47 PM
#44
Interesting, I've always had the timing checked.
Maybe Sacramento has tighter restrictions and that's why they test the timing, I don't know. I do know it takes less than 5 minutes to get it timed and I'm of the opinion that getting everything perfect for the physical inspection is a good idea.
A friend told me that the smog tech pulled the probe out of the exhaust pipe until it passed. This was a long time ago and I think they now test for that kind of trick.
One good thing is, unlike back East, they don't go through the car for its annual safety inspection. Considering that their cars back there rust big time, that might not be a bad idea. For them...
Originally, CA was going to have a sliding date that you no longer needed to worry about smog after 25 years after the manufacturing date. Now I think you're only exempt up to 1974???
Kind of like how they said they'd NEVER pull you over if they didn't see you wearing a seat-belt when Ca. adopted the seat belt laws in 1986. Next thing you know, it's click it or ticket! No matter, I always where my seat-belt anyway bit it's still just a revenue enhancement except for little kids.
10-18-12, 06:10 PM
#45
i know for a fact that putting wood alcohol (methanol) or octane booster or even propane will "cheat" your way through a smog test
does it work on rotary engines? i have no clue
i did it for my mazda pickup
does it work on rotary engines? i have no clue
i did it for my mazda pickup
10-18-12, 06:30 PM
#46
Why don't yall just convert to LP anyway. To hell with this smog test crap.
Conversion is not hard just find the holly throttle body and get a regulator to match with the RB Holly intake manifold... done.
I'm doing the same thing to a briggs 8hp side shaft and a honda 11 propane throttle body (its called a carb but it has very little to do with atomizing so i call it a throttle body). I'm gonna put it on a minibike.
Conversion is not hard just find the holly throttle body and get a regulator to match with the RB Holly intake manifold... done.
I'm doing the same thing to a briggs 8hp side shaft and a honda 11 propane throttle body (its called a carb but it has very little to do with atomizing so i call it a throttle body). I'm gonna put it on a minibike.
12-06-12, 11:57 AM
#48
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it'll work on a rotary too, you might need different proportions than a normal piston engine.
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