High Hydrocarbons....

General engine questions/issues that aren't specific to the other categories
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High Hydrocarbons....

By Greasedmonkey
- Mon Mar 14, 2011 10:42 pm #243908 Im having this problem. Ive been trying to get the car inspected. Its failed 3 times now. Each time it fails because of high hydrocarbons. Everything else passes great.

Ive replaced the plugs and rotor. The cap still looked good and the wires arent that old. A year maybe. The o2 sensor was replaced last year with a new OEM one from honda.

I really need to get this passed. This is annoying the crap out of me. Any help is appreciated.
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By Punksz6
- Tue Mar 15, 2011 12:52 am #243929 Have you tried the cat yet?
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By Greasedmonkey
- Tue Mar 15, 2011 7:29 am #243991 the cat is my next attempt. Im wating on my quote to come back for a new one.

I know about that link. most of that isnt happening on the car.

The only odd thing is when you get on it, going through the whole rpm range, you will get some exhaust smell inside the car. Pretty bad. But only when you get on it. normal driving doesnt do it.
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By ghskid06
- Tue Mar 15, 2011 8:04 am #243996 Hopefully the cat solves your problem. Maybe the smell will go away too. Better to replace your pcv valve either way though. I think they are supposed to be replaced every 12k. They can cause exhaust smell if bad.
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By suspendedHatch
- Tue Mar 15, 2011 5:21 pm #244043 Do you have a chip, hack, or piggyback? Do you have an adjustable fpr, cam gear, or other-than-stock injectors or fuel pump?

Can you post your O2 and CO2 numbers?

Do you have even compression between cylinders?
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By Greasedmonkey
- Tue Mar 15, 2011 10:09 pm #244097 HC@ 2626rpm = 51 : Standard is 220
HC@ 965rpm = 538 : Standard is 220

C0@2626 = .34 : Standard is 1.20
C0@965 = .37 : Standard is 1.20

Co2@2626 = 13.9
co2@965 = 12.9

Stock ecu, injectors, fpr and fuel pump.

Car has short ram and a no name header. o2 sensor is in the stock location.

Car has compression. Not sure on the numbers. Should be able to check them tomorrow.
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By slowj1
- Tue Mar 15, 2011 10:38 pm #244103 why is the rpm 965? Seems low to me. Is this a dyno test? In cali we have tests for 15 and 25 mph. I'll have to look at my smog test to see where the rpm is at 25mph.
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By Greasedmonkey
- Wed Mar 16, 2011 9:43 pm #244316 They bullshit about my car being too low to get on the dyno. Its never had a problem before. So I guess they are doing it on the ground just reving it up to those rpms.
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By Ajax1989
- Wed Mar 16, 2011 10:05 pm #244322
Greasedmonkey wrote:They bullshit about my car being too low to get on the dyno. Its never had a problem before. So I guess they are doing it on the ground just reving it up to those rpms.


but that doesnt put a load on the motor
:eh: sond like they have fucked up laws like cali :thumbdown:
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By slowj1
- Wed Mar 16, 2011 11:29 pm #244337
Greasedmonkey wrote:They bullshit about my car being too low to get on the dyno. Its never had a problem before. So I guess they are doing it on the ground just reving it up to those rpms.


I would take it some where else to get a proper test. It could pass and you don't have to have the headache anymore. Oh and i looked at my rpm's on my test and it was about 1900 at 15mph and a little over 2000 at 25mph.
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By Greasedmonkey
- Thu Mar 17, 2011 12:43 am #244352 Imma ask them this last time to put it on the dyno. I feel that it would do better.
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By suspendedHatch
- Fri Mar 18, 2011 5:15 pm #244699 They don't measure O2 in Texas? That makes it harder to diagnose. Your CO2 is a little low but w/out knowing the O2 readings...

They're giving you the two-speed idle test. It should have no problem passing that. In most states they only give you that if you're dedicated 4WD, but I can see them doing it if you're too low. Dynos cost a fortune and damaging it can put them out of business.

Can they do it at 1200 RPM instead of 900? 900 is considered high idle and I wonder if the ECU is trying to bring the idle down by retarding the timing and leaning the fuel. That would cause high HC.

965 RPM isn't what your car normally idles at, is it? It should be around 750.
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By Greasedmonkey
- Sun Mar 20, 2011 6:12 pm #245053 sorry, i just put up what showed pass or fail.

o2 @965 is 3.1%
and @2626 is 1.5%
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By suspendedHatch
- Sun Mar 20, 2011 6:33 pm #245058 Okay the presence of O2 and the low CO2 indicate that you are running lean. It goes along with my theory that running 900 RPM puts the ECU in a state of high idle and it's trying to bring the idle down to ~ 750.

When you do the two speed idle test you're supposed to test it at idle and then at 1200 RPM.

I would take it to a different place rather than try to tell them how to do their job.
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