Failed smog, 357 HC ppm with the max allowed being 200 @ 2500 RPM.. advice?
02-18-2009, 12:55 PM
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Failed smog, 357 HC ppm with the max allowed being 200 @ 2500 RPM.. advice?
The idle reading was 153 with the max allowed being 200.
I just had a tune up + oil change two weeks ago, changed the rubber intake boot last week, car seems to be running the best it has in years.. yet the smog fail.. hmm..
Edit - Also, new knock sensor, o2 sensor as of last year.
Also, I always use 91 or 94 octane (94 was in the tank for e-test). Recently, someone has pointed out that these cars should run on regular, as RON91 on the gas cap equates to our 87.. would this help at all?
I just had a tune up + oil change two weeks ago, changed the rubber intake boot last week, car seems to be running the best it has in years.. yet the smog fail.. hmm..
Edit - Also, new knock sensor, o2 sensor as of last year.
Also, I always use 91 or 94 octane (94 was in the tank for e-test). Recently, someone has pointed out that these cars should run on regular, as RON91 on the gas cap equates to our 87.. would this help at all?
02-18-2009, 01:52 PM
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Taken from 20V.org
High HC - Hydrocarbons - Indicates a misfire condition (incomplete or
inefficient combustion).
* Ignition problems
* Carbon deposits in combustion chamber
* Overly lean A/F mixture
* Increased camshaft overlap
inefficient combustion).
* Ignition problems
* Carbon deposits in combustion chamber
* Overly lean A/F mixture
* Increased camshaft overlap
02-18-2009, 03:15 PM
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nope... not 87... 91...
You'll get knocking with 87 if you push it hard. However, you may get a more complete burn with 87 when testing emissions... because the fuel/air is closer to it's detonation point to begin with, then you add spark.
Better off to change the oil right before the test... not two weeks before. Every little bit helps!
Put some new plugs in?
New cap/rotor (or clean up the one thats in there?
Verify no vacuum leaks around the ISV or anywhere like that.
Good strong grounds for a strong spark.
start looking at mixture settings.
Better off to change the oil right before the test... not two weeks before. Every little bit helps!
Put some new plugs in?
New cap/rotor (or clean up the one thats in there?
Verify no vacuum leaks around the ISV or anywhere like that.
Good strong grounds for a strong spark.
start looking at mixture settings.
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02-18-2009, 06:04 PM
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Got a bentley? The details for what amperage values to expect are listed in there...
only one way to learn... do it! This is assuming someone has drilled out the plug in the fuel dizzy to let you get an allen key in there. Otherwise... skip... thats something I've never done.
02-19-2009, 08:50 AM
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FWIW, I passed CA "hightened testing" on 91oct w/ injectors + chip, headers, exhaust etc etc
And actually passed with flying colors. I had originally failed HC @ idle (due to a blown PCV tube, bad TPS sensor, and some vac leaks). Fixed all that, did a tune up, changed the oil the night before the test and went from 141 HC @ idle to 36 HC @ idle (120 Max).
I think you're on the right track with the A:F mixture.
I think you're on the right track with the A:F mixture.