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high HC emissions


IDDYMEANDMY's Avatar
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08-02-03, 01:42 PM   #1  
high HC emissions

Hi!

Any thoughts on why on my emissions test my HC levels were high? I did pass. My number was at the allowed amount, the very same no., so one more and I would have failed. I am idling high (at 1798 instead of 1000). "Check Engine" light comes on and off. Am having idling problems (have for over a year) - hace to keep giving ger gas at all times or she will stall. Oh, please do not say get a new car. Could not dare to part with her.

Thank you for your time!

1989 Geo Spectrum/automatic/not turbo/165,000 miles

 
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08-02-03, 05:02 PM   #2  
First step - drive by your local AutoZone parts place, if you have one in your area, and have them read your codes. Take it from there. If no AutoZones, check with other big parts places, most are doing check engine code reading free (they want to sell you the repair parts if you need any.

Several items come to mind with your problem. Post back with what the codes say.

Has the vehicle had regular preventive maintenance? For instance, when was the last time it had spark plugs & wires replaced? Oxygen sensor ever been replaced?

 
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08-02-03, 09:58 PM   #3  
tazzilla
High hc is unburned fuel. This is due to a rich fuel mixture. If your engine oil is dirty that will cause higher hc if you have a weak spark in the cylinder that can cause high hc. check these first

 
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08-02-03, 10:30 PM   #4  
when the check engine light is on---it means something is wrong

when it idles at 1800rpm--it means something is wrong

when your HC is that high---it means something is wrong



like tazzilla said--hc is unburned fuel coming out the tailpipe, and you are at the maximum allowed by the state, picture dollar bills flowing right out of your tailpipe for the last year.

like the tow guy said, get the check engine light checked for free at autozone, write down what they tell you and post those numbers/descriptions here.

somebody should be able to help you fix all three

 
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08-03-03, 04:52 AM   #5  
Joe_F
All are correct. Give us some maintenance history on the vehicle---we can then advise.

It could also be in the carburetor, if so equipped (I think some of these are still carbed in 1989)---can get expen$ive on these foreign ones.

 
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08-03-03, 06:37 AM   #6  
HC's result from misfires or incomplete combustion,a rich mixture causes high CO readings.A compression test would be in order for a car with that mileage,possible valve,headgasket,timing way off (valve or ignition),wire,vacuum leak or plug problem causing high HC's.You can get a rich misfire but CO would also be affected.You don't state all the readings however.

 
IDDYMEANDMY's Avatar
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08-03-03, 10:30 AM   #7  
Hi!

Thank you for all the info. Here is some additional info.:

CO% was fine at .53 with 1.39 allowed. Oh, there are two categories with the emissions: A "25/25 test" and a "50/15 test" I was at the allowed limit with HC on the "25/25 test" and better on the "50/50 test" at 158 with 223 allowed. All other readings were good.

The O2 sensor has been replaced, new plugs and wires, recent oil change, new air filter. The carburetor intake area was quite dirty so used carb cleaner spray to get rid of that. Did that days before the test. The car has had regular oil changes. Had a diagnostic test performed at the dealer last year when I first started to have to drive with two feet, feding her gas constantly as to not stall. I have to go find that. Sorry. Were two codes. At the time. the dealer suggested a new carburetor. Said new one would cost $1000 from them and suggested that I go to an carb expert and get a rebuilt one or have mine rebuilt.

Should add that I did not have a high idle until after she returned from having her timing belt and water pump changed out. I figure the shop where I took her up-ed the idle not knowing about my two footing thing. They never mentioned a thing about it. Wanted to take her back and fuss, but the check engine light was staying off. It like never came on. That was about a month ago and now that blasted thing is on all the time. Checked the O2 sensor and it was sooty. Cleaning that made a big change with the light coming on here and there, but at times staying on until the car was turned off. I know I need a new car. She has oil leaks and a transmission leak. I keep an eye on them and check my fluids often. Hate the thought of a new car.

Will get back with more info.

Thank you all so very much!!

 
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08-03-03, 12:06 PM   #8  
Still recommend a code read if you haven't had one done. May point you right to the problem and it costs nothing.

 
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08-03-03, 04:13 PM   #9  
Joe_F
Yup, an OEM carburetor exceeds the value of this thing.

Find a GOOD shop that can rebuild it and go through it thorougly. That and new vacuum lines should help straighten things out a bit.

 
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08-04-03, 05:03 PM   #10  
tazzilla
Originally posted by mike in nj
when the check engine light is on---it means something is wrong

when it idles at 1800rpm--it means something is wrong

when your HC is that high---it means something is wrong



like tazzilla said--hc is unburned fuel coming out the tailpipe, and you are at the maximum allowed by the state, picture dollar bills flowing right out of your tailpipe for the last year.

like the tow guy said, get the check engine light checked for free at autozone, write down what they tell you and post those numbers/descriptions here.

somebody should be able to help you fix all three
If the check engine light was on it would have failed the smog!!!

 
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08-04-03, 05:52 PM   #11  
Joe_F
Not always true. My mother's Saturn had been intermittently turning on the MIL lamp and it flew through the NYS dyno test less than a month ago.

I have since rectified the problem.

In all honesty, some states can/will fail you for an MIL during inspection.

 
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08-04-03, 07:49 PM   #12  
knuckles
PA & DE both require that the MIL functions properly and is OFF in order to pass emissions inspection. Laws & test procedures vary from state to state, sometimes county to county.

The fact that the MIL is on does not necessarily mean that the car would fail a tailpipe test. A failure in any monitored component can trigger the MIL. The PCM monitors many components (such as the torque convertor clutch) that won't have a direct effect on tailpipe emissions, but can have an indirect effect. A slipping TCC=lower fuel economy & increased emissions. The increase in emissions won't necessarily cause the car to fail the emissions test, but it will trigger the MIL.

 
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08-05-03, 08:24 PM   #13  
Knuckles..... in NC also, on 1996 and newer. The MIL can be on without a failure on 1995 back in NC.
Billy

 
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