Emmisions Fail....Help!

[accordztech]

meh could be clogged egr ports

if so, then nox numbers would be higher and you would feel a definite missfire.

But Nox is also hidden with co is high. But if co is high then something is contributing to it.

WHen was the last time the car had a tune up, check your cap and rotor and the spark plugs.

[wed3k]

if so, then nox numbers would be higher and you would feel a definite missfire.

But Nox is also hidden with co is high. But if co is high then something is contributing to it.

WHen was the last time the car had a tune up, check your cap and rotor and the spark plugs.

doubt it, CO is a mixture/tune issue. not "clogged" but could be restricted.

[Marko13]

So are you guys saying check the egr and replace the o2 sensor? If the o2 sensor was bad though wouldnt i be throwing a CEL?

[cloudasc]

If the o2 sensor was bad though wouldnt i be throwing a CEL?

Not usually. Our cars are obd1, and only have 1 o2 sensor, obd2 cars have two, which for all intensive purposes, is a check and balance system. The ecu can detect wrong readings from the o2 sensor, since there is another one to compare too. Ours, if were lucky we might get a o2 heater code, otherwise you when its on its way out it could take 2-3 hours of it sputtering and wanting to stall out intermittently, before it even throws a code 43. (in my case). Otherwise there have been people who have what appears to be normally functioning o2 sensors, but something ends up being off with them, like they decalibrate over time, and it causes them to fail their smog test.

[accordztech]

doubt it, CO is a mixture/tune issue. not "clogged" but could be restricted.

You have a point there, but it can go both ways. If co is high, then it can be hiding some of the NoX readings. But if its because of the nox behing high and clogged egr ports, it can cause co to be high because of a small misfire.

So are you guys saying check the egr and replace the o2 sensor? If the o2 sensor was bad though wouldnt i be throwing a CEL?

Not exactly as someone pointed out. But a O2 sensor CEL wont go off if the sensor is still working. Lets say the sensor was bias Lean, it will always think that the burn is lean so its telling the comptuer to richen up...it wont set off a check engine light because it still sending a signal.

A bias Lean O2 sensor can cause the high co readings as well. Car thinks its burning lean, dump more fuel to compensate.

[wed3k]

in this case way more fuel. switching time is probably really slow but the computer isn't smart enough to look for that. it has no code set criteria...only for low or high voltage.

and remember that a miss would affect hc.

you and i need to have a beer next time, we have a lot to discuss

[accordztech]

in this case way more fuel. switching time is probably really slow but the computer isn't smart enough to look for that. it has no code set criteria...only for low or high voltage.

and remember that a miss would affect hc.

you and i need to have a beer next time, we have a lot to discuss

DUDE all this time I was reading HC as being high....shit lol I did it again. damnit!

[accordztech]

you and i need to have a beer next time, we have a lot to discuss

So, were you refering to me?

[wed3k]

who else?

[accordztech]

who else?

Lol the op.

[My300kCoupe]

Now correct me if im wrong, but from my understanding, a JDM engine has a totally different emissions standards than a usdm engine. Im not 100%, but from what ive reserched, Its extremely difficult to get a JDM engine to pass USDM emissions. I mean, damn, it took me 2 weeks to get my f22a4 to pass emissions! But anyway, i floped them by 3x the legal limit. I did a total tune up, cleaned egr and egr ports, valve adjustment, reset ignition timing,(mine was advanced a bit), replaced the distributer with a spare that i had gone through entirely, and ran some lucus oil injector cleaner through it. Now this part may sound totally absurd, but i ran about 2 bottles of water throught my throtle body. Now hear me out... If you take a peice of vacume hose and dip it into a bottle of water, plug the end with your thumb, then run a few drops at a time through the intake, it sort of works as a steam cleaner for you valve system. it breaks up alot of the buld-up on the valve system. It filled the whole street up with white smoke for the 1st bottle. just keep doing it untill it stops smoking, then go run the piss out of the car. My car literally filled entire intersections with white smoke, but promptly cleared up, and then i went straight to the emissions station and passed. DO NOT go overboard with puting water in your engine! That should go without saying.

[accordztech]

who else?

Maybe I will be at the next heather farms meet, maybe

[cloudasc]

Now correct me if im wrong, but from my understanding, a JDM engine has a totally different emissions standards than a usdm engine. Im not 100%, but from what ive reserched, Its extremely difficult to get a JDM engine to pass USDM emissions.

Thats because most people who bring over a JDM engine, are running a JDM ecu. Which is tuned for JDM emissions, which one would think would be stricter considering they have the 2liter tax, but doesn't appear to be the case. If someone is having problems passing emissions in the 49 states (not cali) with a USDM engine, there might be a benefit to running a cali emission ecu. (I still haven't gotten any roms for the pt3/pt6 that are cali emission, maybe one of these days I'll pull the rom off my PT6-L50.)

[wed3k]

my dad's es300 with a jdm motor passed emissions fine with the original cat @ 230k.

as long as the jdm engine has usdm emissions components then there's no way it can run worse.

and you're not supposed to drop water in, id prefer to use a spray bottle at a higher rpm.