I am fed up, car failed emissions again... high on HC @ idle again
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Joined: May 2006
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I am fed up, car failed emissions again... high on HC @ idle again
either i have over looked something, or this shop is shady. I doubt the later. there is no logical reason for it to be failing on HC.
Only possible thing in my mind is if it is infact running lean at idle. but it shouldnt be. it also has been getting poor mileage. that makes no sense either. I am about to put some of that guaranteed to pass BS in it and get the hottest plugs i can find.
>:X
i have done the following:
New O2 sensor
new air filter
complete cleaning or throttle body and intake
Cleaned MAF sesnor with Isopryol alcohol
new plugs
new cap and rotor
new wires
fresh oil and filter
cleaned ISV
new thermostat (was running cold)
ran seafoam through the motor (intake)
run techron through the motor (fuel)
unbolted the cat, looks to be in perfect condition
traced every vacume line, no leaks
cleaned full PCV system
only red flag i have found it that when the oil cap is removed the motor does not die, doesnt sputter, doesnt do anything. shouldnt it die from the vacume leak created? yet i dont think it has tuned itself for a massive leak because opening up any port on the intake manifold such as the ISV inlet kills it.
this thing is pissing me off, i only have about an hour at a time to screw with it and i am drawing a blank on why the damn HCs wont come down.
Only possible thing in my mind is if it is infact running lean at idle. but it shouldnt be. it also has been getting poor mileage. that makes no sense either. I am about to put some of that guaranteed to pass BS in it and get the hottest plugs i can find.
>:X
i have done the following:
New O2 sensor
new air filter
complete cleaning or throttle body and intake
Cleaned MAF sesnor with Isopryol alcohol
new plugs
new cap and rotor
new wires
fresh oil and filter
cleaned ISV
new thermostat (was running cold)
ran seafoam through the motor (intake)
run techron through the motor (fuel)
unbolted the cat, looks to be in perfect condition
traced every vacume line, no leaks
cleaned full PCV system
only red flag i have found it that when the oil cap is removed the motor does not die, doesnt sputter, doesnt do anything. shouldnt it die from the vacume leak created? yet i dont think it has tuned itself for a massive leak because opening up any port on the intake manifold such as the ISV inlet kills it.
this thing is pissing me off, i only have about an hour at a time to screw with it and i am drawing a blank on why the damn HCs wont come down.
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Joined: Dec 2004
Posts: 4,628
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Did you adjust the idle mixture?
There's a series of things to this step see Bentley for details... Maybe you have a pissing injector or something weird. Have you given it the Italian tune up?
HC is unburned fuel right? so it's running rich. Check the plugs for signs of this. But like I said it could be poor fuel atomization.
HC is unburned fuel right? so it's running rich. Check the plugs for signs of this. But like I said it could be poor fuel atomization.
Thread Starter
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Joined: May 2006
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I have always been taught that HC at idle is a lean condition, i have not touched the mixture at all
plugs are all a little too clean, this is telling me lean condition. there is no unburnt fuel coming out the exhaust in anny excessive amounts, so i am ruling out misfires
AudiWorld Member
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Re:Only if its as lean miss
Do you have a recent cat. in the car. I used to be a cal emissions inspector. I used to have a lot of problems with the 7A engines. Their hard on the converter. I would try replacing it.
Senior Member
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Your injectors are shot! Hitachi crap is killing you. Change over to 034's.
Failed HC means unburnt fuel...not a lean condition.
Your injectors are dumping too much fuel into engine. Sure sign of it?.....go too back of car while car is running...does your eyes sting a little or you smell fuel back there? Bingo!
Your cat is probably shot too from the unburnt fuel flowing thru there.
Your injectors are dumping too much fuel into engine. Sure sign of it?.....go too back of car while car is running...does your eyes sting a little or you smell fuel back there? Bingo!
Your cat is probably shot too from the unburnt fuel flowing thru there.
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Re: Oxides of Nitrogen are related to heat. During if it pings (detonation)
Nox goes way up. But if the engine misfires you're going to get a big gulp of HC. HC is unbured gas. HC also relates to how efficient the engine is newer engines produce less HC than a worn engines, not saying that yours is worn out. That is one of the factors in the Japans emissions policy of engine change at 30k.
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Thread Starter
Senior Member
Joined: May 2006
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wouldnt the plug be nasty looking if it was rich and pushing unburnt fuel around?
i planned on getting o34s kit, just dont have the cash right now.
btw- your o2 write up was a big help as i had never done one on this chassis, thanks
btw- your o2 write up was a big help as i had never done one on this chassis, thanks
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