CA smog: what causes my bad smog report?
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CA smog: what causes my bad smog report?
Here's my actual smog report. This car has always passed easily and I put in a Bonerz cat about 5 years ago. But last year I replaced the intake manifold orings, or rather, my inept mechanic did. Since then it will only hold an idle when warm, and at 400rpm, so I have to do something.
It failed a "test only" smog test.
I'd rather have someone else do it.
I appreciate any light anyone can shed on this.
I want to sell this car, but vehicle prices have gone thru the floor around here because of gas prices and general economic misery.
It failed a "test only" smog test.
I'd rather have someone else do it.
I appreciate any light anyone can shed on this.
I want to sell this car, but vehicle prices have gone thru the floor around here because of gas prices and general economic misery.
Last edited by bliffle; 09-10-08 at 11:24 PM. Reason: misspelling
#2
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Is your car running really lean? I think this because of your low NO numbers. Could this lead to high CO and HC numbers and also high CO2 levels? It is a good thing there is not any O2 because your catalytic converter is working.
I am not too sure but it could be possible that the engine should be rebuilt to be running clean and the car able to sell. Good luck
I am not too sure but it could be possible that the engine should be rebuilt to be running clean and the car able to sell. Good luck
#3
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0% o2? that's pretty extreme.
Low o2, low NO, very high HC, high CO2... to me, that says extreme rich mix, or an air-control valve problem.
You're consuming absolutely all available oxy, and still not burning the HC's.
Low o2, low NO, very high HC, high CO2... to me, that says extreme rich mix, or an air-control valve problem.
You're consuming absolutely all available oxy, and still not burning the HC's.
Last edited by DivinDriver; 09-11-08 at 11:31 AM.
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rich
NOX is usually high if it is running lean and low if rich. Your HC is high indicating a rich mixture OR misfire. Is this on a carbureted 12A or on a fuel injected 13B SE?
A full tuneup and a shot of seafoam would be a good start.
A full tuneup and a shot of seafoam would be a good start.
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This is a stock 12A with nikki carb, low mileage, and never has been a problem. But it's been sitting around unused (except for weekly airing out), but it's been idling low ever since I replaced the manifold gasket and orings.
Seems to run good above idle.
Seems to run good above idle.
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your problem is probably related to the low idle. since it happened AFTER the intake gasket change, that would be the first place to look.
#7
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I hope it can be solved by adjusting the idle and mixture screws. I have the instructions from Sterling, I have the loooonnngg shaft screwdriver, now I have to remove the air cleaner (the whole canister, I think) to get at the screws and I have to cut off the factory cap (Dreml?) over the mixture screw. Then walk it thru the adjustments.
Has anyone ever tried "Smogtips"? they have a scheme where you crank the numbers, etc., into their form, along with any other info, and for $20 they diagnose it. After carefully transcribing the data into their form for about a half hour I paid the $20 and now I await their diagnosis in my email.
I'll check that before I pop the air cleaner off.
"Smogtips" provides the service *free* if you use one of their test stations, so I'm going to test ANOTHER car this afternoon at a Smogtips station (I got a $49 full price coupon).
Then, after all that, I have to "Test only" my 83, too, but that's usually a breeze (just one of the reasons it's my favorite alltime car).
Has anyone ever tried "Smogtips"? they have a scheme where you crank the numbers, etc., into their form, along with any other info, and for $20 they diagnose it. After carefully transcribing the data into their form for about a half hour I paid the $20 and now I await their diagnosis in my email.
I'll check that before I pop the air cleaner off.
"Smogtips" provides the service *free* if you use one of their test stations, so I'm going to test ANOTHER car this afternoon at a Smogtips station (I got a $49 full price coupon).
Then, after all that, I have to "Test only" my 83, too, but that's usually a breeze (just one of the reasons it's my favorite alltime car).
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#9
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I just rocked mine up and down until the tang snapped, years ago.
(The Cali air mix screw smog caps are different from the rest - - they are a metal can that prevents you from reaching the screw with anything except a very special "security" screwdriver. They're atttached to the carb by a screw through a metal tang at the bottom. You can only pull the screw by removing the carb, but it's not that hard to bust the cap off.)
(The Cali air mix screw smog caps are different from the rest - - they are a metal can that prevents you from reaching the screw with anything except a very special "security" screwdriver. They're atttached to the carb by a screw through a metal tang at the bottom. You can only pull the screw by removing the carb, but it's not that hard to bust the cap off.)
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I'll try rocking the cap , after I remove the air cleaner : the whole thing, to get access to the two screws.
Meanwhile, I gotta lean out my 83 which flunked with high HC because it's running too rich. I leaned it down 4 half turns today to where it barely started hunting, and then backed it out 1/4 turn.
Meanwhile, I gotta lean out my 83 which flunked with high HC because it's running too rich. I leaned it down 4 half turns today to where it barely started hunting, and then backed it out 1/4 turn.
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My 83 failed too, just barely.
I can see the mixture screw on the 83, so, since the idle was good, I started the tuning process with the mixture screw by turning it in (CW) until it started to hunt, then backed off 1/4 turn. The screw went in 2 whole turns before it started to hunt, and since the cap was missing I conclude that a previous smog checker had adjusted it and left it too rich and that's why I failed last week.
I'm going to put in fresh plugs and check timing then take it back to the "Test Only" station and get my free re-test. I figure it will pass this time. If not, I'll have to do more.
Too bad I don't have someway to test before going in.
I can see that the 85 has the screws buried under more stuff than the 83 has. But even on the 83 it's almost impossible to reach the idle speed screw without removing the air cleaner assembly. Fortunately, I don't think I have to.
Here's the 83 smog test result:
I can see the mixture screw on the 83, so, since the idle was good, I started the tuning process with the mixture screw by turning it in (CW) until it started to hunt, then backed off 1/4 turn. The screw went in 2 whole turns before it started to hunt, and since the cap was missing I conclude that a previous smog checker had adjusted it and left it too rich and that's why I failed last week.
I'm going to put in fresh plugs and check timing then take it back to the "Test Only" station and get my free re-test. I figure it will pass this time. If not, I'll have to do more.
Too bad I don't have someway to test before going in.
I can see that the 85 has the screws buried under more stuff than the 83 has. But even on the 83 it's almost impossible to reach the idle speed screw without removing the air cleaner assembly. Fortunately, I don't think I have to.
Here's the 83 smog test result:
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It's probably because the new smog tests require a dynomometer for the actual pass/fail test.
Anyway, I still have to figure out what to do about the Fuel Evaporative Test, i.e., the charcoal canister that recycles gas back to the tank. I think that what's indicated is a leak in the return hose.
Anyway, I still have to figure out what to do about the Fuel Evaporative Test, i.e., the charcoal canister that recycles gas back to the tank. I think that what's indicated is a leak in the return hose.
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Nuts! The 83 failed again, with even higher HC!
I leaned it out to where it started to stumble and hunt, and then backed off (CCW) 1/2 turn. Changed plugs, added some alcohol to the tank, and the HC is even higher!
Could be a leak in the carb (except this engine never runs rough and never backfires), but why would that be worsened by leaning the idle mixture?
I'm at a loss to explain it, or know what to try next on the 83.
Haven't touched the 85 until I get the 83 clear.
I leaned it out to where it started to stumble and hunt, and then backed off (CCW) 1/2 turn. Changed plugs, added some alcohol to the tank, and the HC is even higher!
Could be a leak in the carb (except this engine never runs rough and never backfires), but why would that be worsened by leaning the idle mixture?
I'm at a loss to explain it, or know what to try next on the 83.
Haven't touched the 85 until I get the 83 clear.
#17
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Nuts! The 83 failed again, with even higher HC!
I leaned it out to where it started to stumble and hunt, and then backed off (CCW) 1/2 turn. Changed plugs, added some alcohol to the tank, and the HC is even higher!
Could be a leak in the carb (except this engine never runs rough and never backfires), but why would that be worsened by leaning the idle mixture?
I'm at a loss to explain it, or know what to try next on the 83.
Haven't touched the 85 until I get the 83 clear.
I leaned it out to where it started to stumble and hunt, and then backed off (CCW) 1/2 turn. Changed plugs, added some alcohol to the tank, and the HC is even higher!
Could be a leak in the carb (except this engine never runs rough and never backfires), but why would that be worsened by leaning the idle mixture?
I'm at a loss to explain it, or know what to try next on the 83.
Haven't touched the 85 until I get the 83 clear.
I searched what would be a good ratio mix for the alcohol:gasoline mix and found a few different responses. I do not recall exactly how much I was recommended but I believe it was 1:2 alcohol:gas mix ratio.
Besides having the engine fully tuned up (plugs, oil change + filter, clean air filter, etc.) right before a smog look at the emissions equipment.
For myself I found out that my air control valve was malfunctioning. The car would run fine but I did a test (disconnect rubber recirculating pipe from ACV to bottom of air cleaner cover unit and rev engine past 2500 rpm). If more air flows out still as rpms increase, your CA ACV is not working right and there is no air flow to your catalytic converter to burn hotter and efficiently clean all the emissions. This can be a pricey fix.
Again let us know how the results go. Good luck! Hope you pass soon and get your car on the road legit!
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ACV, eh? Well, I can see that possibility. A couple years ago while getting a Smog Check on the 83 the mechanic called me and recommended a new cat, so I said OK since it was 'only' $200 installed. But now I wonder if the air tube was hooked up properly and if the cat gets enough air to burn up the HCs that I'm reading high?
I have a spare ACV, but it's a Pick 'n Pull so it may be bad.
I have a spare ACV, but it's a Pick 'n Pull so it may be bad.
#20
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I wish I had more to contribute but all I can say is good luck.
I'm glad I live in an area where this isn't an issue. FBs are SO much easier to deal with when you don't have to worry about emissions control devices.
When I first read the title "CA smog: what causes my bad smog report? " my answer in my head was "Driving an FB" lol.
Jon
I'm glad I live in an area where this isn't an issue. FBs are SO much easier to deal with when you don't have to worry about emissions control devices.
When I first read the title "CA smog: what causes my bad smog report? " my answer in my head was "Driving an FB" lol.
Jon
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Well, I read the California DMV website about smog stuff, and it recommended I call the Bureau of Automotive Repair, so I did. The number is 800-952-5210 and you have to push through a few voice menus, but eventually I got a *human*, who gave me some help and advise. Didn't have to wait long either.
He said that probably all I need is a carb overhaul, replace some gaskets and rotted out rubber/neoprene seals. said that sometimes the carb floats get gas or water inside and sink, resulting in too mush fuel. He was able to hustle up my failed smog charts.
So, if it's not TOO hard I'll overhaul the carb on the 83 and check the ACV and the hose-that-gets-burned while I'm in there.
Or maybe I should just put a Sterling in. Trouble is I need another core carb.
Carb o'haul kits are $46 at rockauto, $60 at NAPA, and $66 at mazdatric.
He said that probably all I need is a carb overhaul, replace some gaskets and rotted out rubber/neoprene seals. said that sometimes the carb floats get gas or water inside and sink, resulting in too mush fuel. He was able to hustle up my failed smog charts.
So, if it's not TOO hard I'll overhaul the carb on the 83 and check the ACV and the hose-that-gets-burned while I'm in there.
Or maybe I should just put a Sterling in. Trouble is I need another core carb.
Carb o'haul kits are $46 at rockauto, $60 at NAPA, and $66 at mazdatric.
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I suppose it's possible, especially since my O2 number is so low.
Too bad I don't have an easier way to check emissions that's better than spending $25 (average) at the Smog shop. I could richen it back out a turn or two.
Has anyone ever seen this?
#24
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Hey glad to hear you are working fast with your ride.
Hopefully if you do need to change your ACV, the one from Pick-n-Pull will work. There are two different kinds of ACV for the Series 2 (1981-1983). One is called "federal" and the other is for California models only. So I made sure I had the right part number for the CA model meant for CA emissions equipment installed on our CA FB. I have a thread about my smog woes and I posted some things I did to pass my car including the ACV part number and gasket part numbers, and other stuff.
Perhaps your carb does need a rebuild. I can not see what hurt it can do, but you say your car is running top notch so that may not be the case necessarily.
OH one more thing! When you put your hand (careful of the hot exhaust heat shields) or whatever to test air flow going to the cats you probably cannot feel it because the air going into the cats are very minimal just enough to make it burn a little hotter. I believe with load on the engine there will be more pressure going back to the cats. But the way I tested to see if an ACV works is by making sure the diaphragm "switches" when revved past 2500 RPM.
Good Luck!
Hopefully if you do need to change your ACV, the one from Pick-n-Pull will work. There are two different kinds of ACV for the Series 2 (1981-1983). One is called "federal" and the other is for California models only. So I made sure I had the right part number for the CA model meant for CA emissions equipment installed on our CA FB. I have a thread about my smog woes and I posted some things I did to pass my car including the ACV part number and gasket part numbers, and other stuff.
Perhaps your carb does need a rebuild. I can not see what hurt it can do, but you say your car is running top notch so that may not be the case necessarily.
OH one more thing! When you put your hand (careful of the hot exhaust heat shields) or whatever to test air flow going to the cats you probably cannot feel it because the air going into the cats are very minimal just enough to make it burn a little hotter. I believe with load on the engine there will be more pressure going back to the cats. But the way I tested to see if an ACV works is by making sure the diaphragm "switches" when revved past 2500 RPM.
Good Luck!
#25
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All the best!