smog check madness

ebodycab

Registered User
my 94 SC 5spd failed CA smog check for fourth time...1st time results:15mph HC max 81 measured 138, CO max 0.47 measured 0.52, NO max 685 measured 1158. 25mph HC max 47 meas 129, CO max 0.44 meas 0.51, NO max 696 meas 1056. I went in without doing anything to the car.
2nd time: I changed new spark plugs and wires and O2 sensors. Results:
15mph HC max 81 meas 158, CO max0.47 meas 0.50, NO max 685 meas 1134,
25mph HC max 47 meas 155, CO max0.44 meas 0.50, NO max 696 meas 1137.
It actually got worse....go figure!
3rd time: I took the octane plugs and put 101 octane gas in the tank($6 a gallon) 15mph HC meas 99(fail), CO meas 0.46(pass), NO meas 412(pass),
25mph HC meas 39(pass), CO meas 0.49(fail), NO meas 378(pass).
NO went down a LOT and passed, CO in the borderline, HC still too high at 15mph. Almost did it! Hooked up the tester and got codes: 118 engine coolant temp sensor, 113 air charge temp sensor, 126 BAP sensor. Changed all three. No other codes. Car runs perfect.
4th time today: I did add gas line antifreeze in the tank with 101 octane and took the octaneplugs out. HC and CO failed again. Frustrated...help?
 
my 94 SC 5spd failed CA smog check for fourth time...1st time results:15mph HC max 81 measured 138, CO max 0.47 measured 0.52, NO max 685 measured 1158. 25mph HC max 47 meas 129, CO max 0.44 meas 0.51, NO max 696 meas 1056. I went in without doing anything to the car.
2nd time: I changed new spark plugs and wires and O2 sensors. Results:
15mph HC max 81 meas 158, CO max0.47 meas 0.50, NO max 685 meas 1134,
25mph HC max 47 meas 155, CO max0.44 meas 0.50, NO max 696 meas 1137.
It actually got worse....go figure!
3rd time: I took the octane plugs and put 101 octane gas in the tank($6 a gallon) 15mph HC meas 99(fail), CO meas 0.46(pass), NO meas 412(pass),
25mph HC meas 39(pass), CO meas 0.49(fail), NO meas 378(pass).
NO went down a LOT and passed, CO in the borderline, HC still too high at 15mph. Almost did it! Hooked up the tester and got codes: 118 engine coolant temp sensor, 113 air charge temp sensor, 126 BAP sensor. Changed all three. No other codes. Car runs perfect.
4th time today: I did add gas line antifreeze in the tank with 101 octane and took the octaneplugs out. HC and CO failed again. Frustrated...help?

how are your cats? Stock exhaust I am assuming? I don't know what to tell you because in Connecticut emissions is so easy to pass
 
Car is all stock with original exhaust and cat's, 155K miles. I guess next thing to do is replace cat's?
 
My Bird has the same smog results .. hasnt been smogged since 02, been on Non-Op while I rebuild the engine.

Plugs, wires, high octane fuel wont do anything for you.

New cats are probably the only way you will pass. There should be 3 .. if you replace the 3rd cat, it might make you pass if you take it in right away, otherwise you'll need to replace the other 2 and you might as well get a little work done at the same time ( at least get rid of that 90 bend on the driver's side cat !! )

Ive heard a cup of rubbing Alcohol in your gas tank will make you pass, but Im not recommending it. :D

Your smog place tested it 4 times ?? Mine will only do one re-test after a fail before you have to pay again. And you are bringing it in when the engine is hot and has been running for a while right ??

- Dan
 
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You're close to passing, so I would suggest:

Replace oil & filter.
Use a quart of gas line antifreeze in a 1/4 tank of premium (not 101).
Temporarily cut the low speed fan wire to pin 14 on the IRCM (so it forces the fan to run on low).
Put the octane plug back in.
Go to a different testing facility.

Good luck.
 
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results of the 4th test(today): 15mph HC meas 93 (went down from 99 but still failed), CO meas 0.46(pass), NO 388(pass), 25mph HC meas 32 (went down from 39, pass), CO meas 0.51(fail), NO meas 400(pass)
First time I went to ARCO Smog pros, one free re-test, second time went to 76 gas station, also one free re-test, smog guy said he will give me one more free test if I change the cats... both times drove the car at least 20 minutes on the freeway and took the test right away, first time I had the fan running all the time(its wired direct to the defroster switch,AC not hooked up), second time didn't have the fan on...needless to say I HATE smog checks...
 
What kind of air filter do you use a freind of minees sc passed with flying colours with gutted cats and he runs a k&n filter but you have to make sure it's clean before u go:)
 
how hard is emissions in california I've heard its pretty hard to pass. Your cats might be hollowed out
 
how hard is emissions in california I've heard its pretty hard to pass. Your cats might be hollowed out

Its got a stock airfilter, new, put it in just before first smog test, did not help, California smog test is way too complicated, I will change the cat's and hopefully that works....
 
x182dan
Here is picture of my test I had done near San Diego in 2004.
They are pretty picky. These results are on my 90 after a new engine, new cats & exhausts. Everything is bone stock except for the exhaust which was a direct replacement from Catco.

dbd
 

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looks kinda like the one here in CT but ours are super easy to pass. Hell even with hollowed out cats I could get a car to pass
 
looks kinda like the one here in CT but ours are super easy to pass. Hell even with hollowed out cats I could get a car to pass

if I get Super Coupe Performance downtubes with hi-flow cat's do I still need the 3rd cat? why 94 5 speeds have 3 cat's? and 94 automatics only 2? my 89 5 speed has only two cat's and has always passed the CA smog test..very confusing....
 
My 94 Auto had 3 cats. The two new cats should help out alot if your current ones are no good. Its more of a visual thing, if the car originally came with 3, it needs to have 3, but alot of smog places dont look under your car unless they are really picky.

- Dan
 
My bad .. yeah the Auto's have 2 cats and one huge resonator ( previous owner replaced it with a Y pipe on my car ) .. Manual's have 3 cats and a small resonator.

- Dan
 
Get yourseif a fuel-system cleaning kit from 'QMI/Full-Throttle' and administer that a few miles before you do your next test.It is almost gauranteed that you will pass, as long as your car is in the stock condition you claim.
You will be amazed...The kit should cost you less than $60. Good luck.
 
My bad .. yeah the Auto's have 2 cats and one huge resonator ( previous owner replaced it with a Y pipe on my car ) .. Manual's have 3 cats and a small resonator.

- Dan

damn I never knew that I figured all sc's had 2 cats one resonator and two mufflers. Thought just the v8s had the 3rd cat
 
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