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failed emissions, where to start?

An American decided to write a book about famous churches around
the world. For his first chapter he decided to write about
American churches.

So he bought a plane ticket and took a trip to Orlando, thinking
that he would work his way across the country from South to
North.

On his first day he was inside a church taking photographs when
he noticed a golden telephone mounted on the wall with a sign
that read $10,000 per call". The American, being intrigued, asked
a priest who was strolling by what the telephone was used for.
The priest replied that it was a direct line to heaven and that
for $10,000 you could talk to God. The American thanked the
priest and went along his way.

Next stop was in Atlanta. There, at a very large cathedral, he
saw the same golden telephone with the same sign under it. He
wondered if this was the same kind of telephone he saw in Orlando
and he asked a nearby nun what its purpose was. She told him that
it was a direct line to heaven and that for $10,000 he could talk
to God. "O.K., thank you," said the American.

He then traveled to Indianapolis, Washington DC, Philadelphia,
Boston, and New York. In every church he saw the same golden
telephone with the same $10,000 per call" sign under it.

The American, upon leaving Vermont saw a sign for Canada and
decided to see if Canadians had the same phone. He travelled
through many towns, cities, and rural villages, again and again
there were the same golden telephones, but this time the sign
under them read "10 cents per call."

The American was surprised so he asked a priest about the signs.
"Father, I've traveled all over America and I've seen this same
golden telephone in many churches. I'm told that it is a direct
line to Heaven, but in every state the price was $10,000 per
call. Why is it so cheap here?"

The priest smiled and answered, "Look around you. Mountains,
lakes, and wide open spaces. Clean air, clean water, and pastures
green. You're in Canada now Son............ it's a local call".
_________________________________________________
 
o.k. very good, i do like it there myself. being from upstate New York it wasn't a far ride up. but theres alot of stuff not being check that mess the air up more. but i do agree with the emissions test, just don't like when i fail them. heck i even hooked all the vacuum lines back up, since the last owner took them off. i still wonder if i got them right? i used the little sticker on the rad cover, but kind of hard to read. is the only vacuum line to the EGR the one at the bottom of the throttle body? i have taken it off with the engine running and its not a great source of vacuum so i hope i have that and the lines on the pass side of the pelnum right? last coupls of 1/2 tanks of gas i have run 2 bottles of furl injector cleaner and i can feel a diff at seating at stop lights with a smoother idle, and other areas too.
 
i friend says i should get a new PCV, lose the K&N air filter for a reg one. what do you all think will it help pass emissions? i put ne plugs in a month ago, i think i am going to pull one out at a time a check to see how they have been firing. dirty fuel injectors cause a high hydorcarbon reading? with the 2 bottles of fuel injection clean in the last couple of 1/2 tanks of gas she seems to be smoother at stop lights and at idle.
 
tigmaned said:
i friend says i should get a new PCV, lose the K&N air filter for a reg one. what do you all think will it help pass emissions? i put ne plugs in a month ago, i think i am going to pull one out at a time a check to see how they have been firing. dirty fuel injectors cause a high hydorcarbon reading? with the 2 bottles of fuel injection clean in the last couple of 1/2 tanks of gas she seems to be smoother at stop lights and at idle.

you want more air going in through the motor not less.

did you change that O2 sensor yet?
 
mic

so your saying don't take the K&N out. haven't changed the O2 yet, been busy. and i have a couple month to get this right.
 
tigmaned said:
mic

so your saying don't take the K&N out. haven't changed the O2 yet, been busy. and i have a couple month to get this right.

That K&N doesn't have any negative affect on emissions.
 
Hydrocarbon is unburned fuel...CO is burned fuel. High CO is generally from running rich...high HC could be an ignition system problem...not burning all of the fuel. If there is even the slightest question about the age of the O2 sensor...REPLACE IT. Same goes for the ignition system...if it's weak you'll get high HC readings.

Another little tip I learned recently...if they do the high-RPM test then the idle test...don't let 'em just drop the throttle from open to idle abruptly. This can load the intake up with fuel for a few seconds and take a while to burn off. Let the throttle come down gradually, and maybe try keep the "idle" RPM as high as the test will allow (it was something like 1300 RPM here for the "tailpipe" test)...that worked for me.

Bill
 
Geek.. is on it here. Also suggest a fresh oil change. PCV check, etc,, but I'm also thinkling 02 sensor. Good luck.


Rick

:w
 
sorry geekinvatte but what dose CO stand for??

whats causing my running rich? when i got the car abot 5 months ago, i put new mobil one in. changed the plugs, cap, rotor. new wires are on the way, as is the ac/delco O2 sensor. when i got the vette there was no vacuum line hooked up to the fuel pressure reg. i hook all vacuum lines back up, and i hope i got it right since i used the sticker under hood. i have checked the FPR for fuel coming out the vacuum line and none, so not sure why the last guy had it discounnected??
at the 2500 rpm test i did fine, idle at 700rpm failed emissions for just hydrocarbons. i was the one that sat in my car and kept the idle were they needed it to be, i can't remember if when the 2500rpm part was done if i just let the gas off the pedal and let it idle, i kind of think i did. i was thinking during the test 2500rpm is pretty fast. this morning coming to work i kept it at 2500rpm i was doing almost 90mpr. i do fell a little miss seating at a idle, but its not repeating constainly, its more sparatic at times.?? not sure whats the cause f that yet?
1986 pretty much stock L98, what octane gas should i be useing? 87, 89. or igh 93?? this tank has 89 in it and my avg snice is 21.5 mpg.
 
CO is carbon monoxide, I think. I was never good at chemistry things.:L

It is unburned fuel that causes that.

Some people question how much the EGR actually contributes to reducing emissions. I guess I'm one of those that questions it.

Another thing could be that your injectors are 20 years old. Have you tested the resistance of the injectors? It could be that they're spraying too much fuel so that it can't be burned off by the plug.
 
Edmond said:
CO is carbon monoxide, I think. I was never good at chemistry things.:L

It is unburned fuel that causes that.

Some people question how much the EGR actually contributes to reducing emissions. I guess I'm one of those that questions it.

Another thing could be that your injectors are 20 years old. Have you tested the resistance of the injectors? It could be that they're spraying too much fuel so that it can't be burned off by the plug.

Yes CO is Carbon Monoxide...the ever so popular toxic by product of burning hydrocarbon fuel. CO is NOT unburned fuel...just the opposite, CO is the result of BURNED fuel. Excess CO means you're burning too much fuel. Since gasoline IS a hydrocarbon fuel....then unburned fuel getting out the exhaust will result in high HC (Hydro-Carbon) readings. That's the "key" to the difference between high HC and high CO...unburned fuel vs. burned fuel (respectively). Another "key" to look at if you CO reading is high....what is the CO2 reading? The catylitic converter's job is to convert CO to CO2...if the CO2 reading is all but non existent and and CO reading is very high...then it's possible the CAT has failed. If the CAT is original then it's most certainly in dire need of replacing.

Bill
 
Do the pup cats help at all with the emissions or are they just there to choke the system?
 
how is it then guys with the fake cats still pass these test???
some thing else i found. with the engine idleing and warm, i notice a slight lope or miss? when i pull off all3 of the vacuum lines off the back right side of intake the engine doesn't run differently. it should run differently, right?? whats this tell me? hey would running a high octane gas help pass the test, i had 87 in at the time.
oh i noticed today my rad fan comes on when my coolant temp gauge reads 170.
 
So what would explain high HCs, high-but-still-passing CO, and great NOx? I also failed my emissions (but they did the full test, not just the idle one) and need to get it done now within a week or two before the deadline runs out.

Tigman, if your fan comes on at 170, you probably don't have a stock chip in your ECU - which might explain why you failed. Stock temp is 230 ON, 195 OFF for our year. Then again, there's a different sensor feeding the ECU than what feeds the dash, so a sensor may be dying.
[RICHR]
 
just got done with a fuel presure test. with it running 39psi. then i shut it off, dropped to 22psi- staying there for 10 minutes, dropped to 20psi- staying there for another 10 miuntes, dropped to 18psi- staying another 10 minutes and i quit there. so by the book 39 psi is right on the money. i see why people take the vaccum line off the FPR, i did it during the test anf fuel perssure went to 44psi.
than i checked most of the vacuum ports and got by my gauge in the normal, green which is betwwen 18 and 22 inch Hg.
but shes still idleing kind of crappy?????
 
what should the vacuum line coming out of the fuel pressure regulator look like?? i have mine going from the FPR to the front vacuum port on the pelnum to the air verter system and the front of the motor.
EGR value vacuum line running to the EGR silanoid, and the other vac lines coming out of it going to the vacuum port coming out of the throttle body.
does this sound right to everyone?
i am wondering if i have a vacuum line thats to strong pulling power from the fuel presure reg to be working right or some thing??
 
late last night i changed most of the old rotted rubber return lines going to the fuel tank and got a new gas cap too. if it doesn't rain after work i'll check my fuel pressure again and see if it drops off like it did before at shut off?? at shut off it went from 39psi to 22psi right off the bat. some tihngs not right?
 
Honestly, most of your fuel pressure loss is probably due to leaking injectors. That's normal in a car with that age. As long as the pressure stays steady while the engine is idling, I wouldn't bang my head against the hood worrying about it.

Check operation of the PCV system - that's important.
Check operation of AIR system - very important.
Make sure TB is closing all the way.

[RICHR]
 
yeah, i still don't think i have the PCV and EGR systems right yet?? i will check the T/B is closeing all the way.
 
from what i can tell the PCV system is right by my sticker on the rad.
the air system is too. i cehcked the throttle body butterfly and it was closed all the way. got a question on that, after the engine is warmed up shouldn't the butterfly be open some to let air in, i pushed the lever on the TPS side and not much risatance from the TPS. i guess only get air at a idle from the IAC vlaue then, i wonder if thatys not working right or not at the right measurement?? some thing else to check....
 

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