won't pass smog
Thread Starter
Heel & Toe
Joined: May 2013
Posts: 15
Likes: 0
From: Anaheim CA
stats / hc meas-153/max59 no meas 776/max692
I did'nt drive it that far only about 2 miles
2 years ago stats were hc meas 47 / max 59 -no meas 102 / max692
I did'nt drive it that far only about 2 miles
2 years ago stats were hc meas 47 / max 59 -no meas 102 / max692
Last edited by 7pryors; Jan 30, 2014 at 10:47 AM.
Safety Car
Joined: Jan 2004
Posts: 3,783
Likes: 15
From: Northern California
High HC levels could be from contaminated oil which contain high HC levels if not changed regularly also, incorrect air/fuel mixture, timing or a bad catalytic converter.
High NOX levels are high combustion temps which could be from a non functioning EGR valve or incorrect air/fuel ratio, (to rich or to lean).
When was the last tune up?
Also, check for recent engine diagnostic codes.
.
High NOX levels are high combustion temps which could be from a non functioning EGR valve or incorrect air/fuel ratio, (to rich or to lean).
When was the last tune up?
Also, check for recent engine diagnostic codes.
.
Last edited by GKK; Jan 30, 2014 at 11:06 AM.
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From: SF bay area C.A.
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When you have more than one high reading it is usually related to the cats. Also 2 miles is not enough, I take mine out on the freeway for at least 10 minutes.
Last edited by kimmer; Feb 1, 2014 at 09:28 PM.
Pro
Joined: Aug 2012
Posts: 663
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From: Nashville TN
I just went through this on my 92 with 103k miles.
No codes but was really rich. I failed with 4x the max allowable readings.
I replaced both 02 sensors and put the best gas I know of, Amoco Ultimate (the clear stuff) and my emissions dropped all the way down to 1/2 of the max. I didn't do anything else to the car.
Last edited by bassackwards; Jan 31, 2014 at 07:56 AM.
Advanced
Joined: Dec 2012
Posts: 89
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From: CARPI ITALY
Yes Sir it's all right
i mean if you have not DTC and have the oxygen sensor good working for to reduce HC need to replace the cats
On my car i have installed long tube headers witout cats and the CO is OK but HC are high
i mean if you have not DTC and have the oxygen sensor good working for to reduce HC need to replace the cats
On my car i have installed long tube headers witout cats and the CO is OK but HC are high
Last edited by robbys65; Jan 31, 2014 at 08:22 AM.
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Joined: Aug 2012
Posts: 663
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From: Nashville TN
My readings before:
HC 719 max allowed 220
CO 8.27 max allowed 1.2
readings after new 02 sensors, nothing else done:
HC 105
CO .67
That is a huge drop in both numbers. They don't test NOx here but I would expect similar results.
HC 719 max allowed 220
CO 8.27 max allowed 1.2
readings after new 02 sensors, nothing else done:
HC 105
CO .67
That is a huge drop in both numbers. They don't test NOx here but I would expect similar results.
Pro
Joined: Aug 2012
Posts: 663
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From: Nashville TN
No it is not a very hard job. I had to use a Husky spark plug socket because it was 1/2" longer than my Craftsman and that made all the difference. Craftsman was to short to clear the manifold and it was too tight for an extension. The extra length made all the difference in saving my knuckles.
Driver side I removed the fender center section and loosened the ABS stuff and moved it out of the way. These cars are lots easier than the Camaros
Driver side I removed the fender center section and loosened the ABS stuff and moved it out of the way. These cars are lots easier than the Camaros