Emissions problem, thoughts?
Thread Starter
Joined: Sep 2000
Posts: 2,374
From: Leesburg,Virginia
Emissions problem, thoughts?
I know that everyone or at least a few of you will say, search for this. I'm sorry I don't have time right now so I was wondering if someone can help me out. I just got my car tested today and I passed everything except for: HC ppm and NO ppm at the higher mph. Can someone tell me what this means or what I can do to fix this problem. By the way I passed the low mph but at the higher mph it failed misserably. Whasts the deal with that?
High HC and Nox can mean the car wasn't warmed up enough, especially with a Y pipe. You need to drive the car at least 30 min before the test. If he tested it multiple times it probably warmed up and your problem is more related to a fuel issue. When was the engine last tuned up? If the sparkplugs are getting old, the fuel may not be burning completely leading to a high HC count. Were they replaced when you put the new engine in? The problem could also be O2 sensor related. If the sensor is starting to get lazy it may not be reacting fast enough to pass the emissions test, but it's still good enough it won't trip a code yet. Those are just a few ideas for you. Good luck.
Thread Starter
Joined: Sep 2000
Posts: 2,374
From: Leesburg,Virginia
My O2 sensor does give a code which says something about increased exaust flow. Also the plugs were not changes after the new engine. I still think that it probably wasn't warmed up enough.
High HC and NOx is usually from a malfunctioning EGR valve, alot of advanced ignition timing and a bad cat. I recommend you check the EGR valve and see if it functions properly. Next clean it or the EGR tube, on the SR20DE the tube tends to get blocked with carbon.
Thread Starter
Joined: Sep 2000
Posts: 2,374
From: Leesburg,Virginia
I have another question. I recently installed a voltmeter and it says that my car is running at 14volts when on, I guess to due to alternator and 12v(normal) when the engine is off. Is this unusual?
Re: Emissions problem, thoughts?
Originally posted by 96BLUMAX
I know that everyone or at least a few of you will say, search for this. I'm sorry I don't have time right now so I was wondering if someone can help me out. I just got my car tested today and I passed everything except for: HC ppm and NO ppm at the higher mph. Can someone tell me what this means or what I can do to fix this problem. By the way I passed the low mph but at the higher mph it failed misserably. Whasts the deal with that?
I know that everyone or at least a few of you will say, search for this. I'm sorry I don't have time right now so I was wondering if someone can help me out. I just got my car tested today and I passed everything except for: HC ppm and NO ppm at the higher mph. Can someone tell me what this means or what I can do to fix this problem. By the way I passed the low mph but at the higher mph it failed misserably. Whasts the deal with that?
Originally posted by 96BLUMAX
I have another question. I recently installed a voltmeter and it says that my car is running at 14volts when on, I guess to due to alternator and 12v(normal) when the engine is off. Is this unusual?
I have another question. I recently installed a voltmeter and it says that my car is running at 14volts when on, I guess to due to alternator and 12v(normal) when the engine is off. Is this unusual?
Thread Starter
Joined: Sep 2000
Posts: 2,374
From: Leesburg,Virginia
Now i know that the autometer afr gauge is inaccurate, but when I turn my lights on i see a drain on voltage on the voltmeter and then my afr guage shows leaner than when i had my lights off. What are you thoughts on this?
you have to rewire your afr gauge. It seems like your experiencing a voltage drop when ever you turn lights on. You need to rewire the main 12 volt source of your gauge preferably direct your your battery and/or even double check your ground connection.
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