High HC output
#1
High HC output
Hey guys I'm new to the forum. I just recently picked up a 1994 4runner and it won't pass smog, the guy told me the HC output is double the limit in California. What would you recommend I do to make it pass smog? I can of course do it illegally but I figured might as well make it run right and handle it the right way.
Thanks for any input!
Thanks for any input!
#2
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You could get it fixed.
It helps to know all the numbers; you have a printout that gives the HC, CO and NOx, at two different speeds.
I'd start with getting the codes. There are dozens of possible reasons for high HC.
And as far as "doing it illegally," good luck with that. In the end, it would be cheaper to buy a 2013.
It helps to know all the numbers; you have a printout that gives the HC, CO and NOx, at two different speeds.
I'd start with getting the codes. There are dozens of possible reasons for high HC.
And as far as "doing it illegally," good luck with that. In the end, it would be cheaper to buy a 2013.
#3
15mph- Max HC- 62/Average- 28/ Mine 107
25mph- Max HC- 37/Average- 17/ Mine 37
Those were the reading for my HC outputs. I figured if I did a tune up (plugs, wires, oils change, cap, rotor,etc) itd help but it's not going to bring it down THAT much unfortunately...
25mph- Max HC- 37/Average- 17/ Mine 37
Those were the reading for my HC outputs. I figured if I did a tune up (plugs, wires, oils change, cap, rotor,etc) itd help but it's not going to bring it down THAT much unfortunately...
#4
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The other (passing) readings can help pinpoint the problem. http://www.autoshop101.com/ technical articles / Emission Analysis is a pretty good short course. You paid real money for those readings; you ought to pay attention to them.
The diagnostic codes are your truck's built-in system for finding the problem. I assume you don't have a CEL (or you would failed just for that), but you could have stored codes.
The "simplest" item to replace that might fix moderately high HC is the oxygen sensor. If it were my truck I'd test it first; the sensors aren't free and the test isn't difficult. But after 100,000 miles replacing one for the hell of it isn't a bad idea.
The diagnostic codes are your truck's built-in system for finding the problem. I assume you don't have a CEL (or you would failed just for that), but you could have stored codes.
The "simplest" item to replace that might fix moderately high HC is the oxygen sensor. If it were my truck I'd test it first; the sensors aren't free and the test isn't difficult. But after 100,000 miles replacing one for the hell of it isn't a bad idea.
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