Emission test failure
#1
Driver
Thread Starter
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Well, it failed as bad as it can be,absolutely ****ed up.
Done at 1720 Rpm
Hc Limit 54 mine 176
Co%Limit 0.30 - 0.32
No Limit 396 - 1444
curb idle test(698 Rpm) is strangely good though
Limit 200 - 151
Limit 1.0 - 0.2
And the car is running fine,idling is fine,no misfires and no codes.I was reading the datastream on the scaner it shows that the egr opens and closes when it should be,all O2 sensor working fine,maf sensor is within limit,shows no malfunction on injectors and there has been no misfire.What the hell can it be to mess it up this much?Only thing i can't check is the Catalityc.Can only the cat converter alone send all those readings up?
Done at 1720 Rpm
Hc Limit 54 mine 176
Co%Limit 0.30 - 0.32
No Limit 396 - 1444
curb idle test(698 Rpm) is strangely good though
Limit 200 - 151
Limit 1.0 - 0.2
And the car is running fine,idling is fine,no misfires and no codes.I was reading the datastream on the scaner it shows that the egr opens and closes when it should be,all O2 sensor working fine,maf sensor is within limit,shows no malfunction on injectors and there has been no misfire.What the hell can it be to mess it up this much?Only thing i can't check is the Catalityc.Can only the cat converter alone send all those readings up?
#2
Lexus Champion
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well you check the cat by measuring the difference between the intlet and outlet temperature [the metal] using IR thermometer
and by banging on it in such a way to tell if its all broken inside
what yr is your car? have you kept up on maintenance? does it have any problems?
i dont quite understand what results you got, it seems jumbled up the way you wrote it.
rewritten by me:
1720 Rpm
HC: Limit 54 Actual 176
C0: Limit 0.30 Actual 0.32
??[?????No Limit 396 - 1444]
curb idle test(698 Rpm)
HC: Limit 200 Actual 151
CO: Limit 1.0 Actual 0.2
is this correct, and further, can you help me understand better, to help you out?
and they didn't do C02 readings nor N0x?
and by banging on it in such a way to tell if its all broken inside
what yr is your car? have you kept up on maintenance? does it have any problems?
i dont quite understand what results you got, it seems jumbled up the way you wrote it.
rewritten by me:
1720 Rpm
HC: Limit 54 Actual 176
C0: Limit 0.30 Actual 0.32
??[?????No Limit 396 - 1444]
curb idle test(698 Rpm)
HC: Limit 200 Actual 151
CO: Limit 1.0 Actual 0.2
is this correct, and further, can you help me understand better, to help you out?
and they didn't do C02 readings nor N0x?
Last edited by llcoolpass; 06-09-09 at 04:17 PM.
#3
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What's the year, and mileage? With NO being that high, my first quess would be egr plugged. Could also be carbon buildup, and injector issues. Sounds like you have a scanner, what are the trims?
#4
Driver
Thread Starter
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It's a '94 with 330.000km.Nox it's terribly high,limit 396 and i have 1444.My scanner says no faults on injectors and i took the egr to pieces and cleaned it 2 months ago,it works fine.O2 behind the converter gave me a code and it was reading 0.0 so i changed it about a month ago,all 3 02 are reading within limits on datastream.I stayed 1 hour today with a propane torch and carb cleaner with the engine idling and found no vacuum leaks.The only thing is the damn Cat converter maybe,is one those cheap aftermarket ones and it sure looks like a monkey welded that in.I had the car for 8 months only and i don't really knows how was maintained but i bet it was not good.Everything tells me there is nothing wrong with the car exept the Cat so i will change that one and the spark plugs and try it again.
Last edited by buci; 06-09-09 at 04:51 PM.
#6
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So all O2 sensors are switching. With NOX that high I can see why you dis-assembled the egr. For a sanity check, I would suggest forcing the egr valve open at idle, and see if the engine stumbles (just to make sure the passageways are open). The other thing with NOX would be compression, could you check a couple cylinders and see what they're running? It may need a good top end clean. Seafoam in the intake does a good job, You might also want to put some in the tank to see of the HC will come down a little.
#7
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One other thing that comes to mind, what are the crosscounts on the downstream O2 sensor, comparded to the upstream? And You are not getting P0420 codes, are you?
Last edited by GEORGE_JET; 06-09-09 at 06:07 PM.
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#8
Driver
Thread Starter
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No,no codes whatsoever and it doesn't burn a drop of oil.What i put in i take out in 6000km.I tried seafoam several times for the past months,on the tank and intake.Car is absolutely stable idling and it's fine at high speed either.It's got to be the Cat converter.
#10
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Have you verified base timming? It's been a little while since my training, but NOX as I recall is not handled by the cat. And the fact that you don't get P0420 would lead me to believe that your cat is working (I am still curious on the ratio of crosscounts). I believe that over advanced, or over retarded timming can also cause high NOX.
These cars appear to be sensitive to cat efficiency and the fact that your car doesn't throw a code for that makes me believe that there is more to this than just a bad cat.
These cars appear to be sensitive to cat efficiency and the fact that your car doesn't throw a code for that makes me believe that there is more to this than just a bad cat.
#11
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One other thought you may want to consider. The air flow sensor on these cars are very easily tweeked, and it is common knowledge. Does it appear that your sensor has been tampered with? Tunners would be aiming at leaning the mixture for increased throttle response, but that would also increase combustion temp and NOX formation.
#12
Lexus Test Driver
iTrader: (22)
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This year model does not have timing. It's DIS. But that's interesting how the smog test is different in Ontario. It's half ASM and half TSI. By the look at the numbers, you car is having a really lean misfire that is why your HC and NOx is high. I would say your 02 sensor is lazy, could be making it bias lean. I would make sure the EGR modulator (most common culprit) works. But I were you, I would just change it because it's easy and not that expensive to replace. Apply vacuum to the EGR see if it stumbles. Next would be the MAF, you can't clean it, but you can check it by lightly tapping on it at idle see if the engine idle changes. If it changes, MAF is bad. But I don't think that is the problem. Lastly, I would check the pre 02 sensors see if they are operating properly. It should go .2 to .8 all the times flucuating within 20-25 sec crosscount. In conclusion, do the modulator first, hopefully you don't have too much carbon build up in your egr passages. After that, the pre 02 sensors. I hope that helps.
Warm the car up before bringing it to a Smog Station ALWAYS.
Warm the car up before bringing it to a Smog Station ALWAYS.
#13
Lexus Test Driver
iTrader: (22)
#14
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This year model does not have timing. It's DIS. But that's interesting how the smog test is different in Ontario. It's half ASM and half TSI. By the look at the numbers, you car is having a really lean misfire that is why your HC and NOx is high. I would say your 02 sensor is lazy, could be making it bias lean. I would make sure the EGR modulator (most common culprit) works. But I were you, I would just change it because it's easy and not that expensive to replace. Apply vacuum to the EGR see if it stumbles. Next would be the MAF, you can't clean it, but you can check it by lightly tapping on it at idle see if the engine idle changes. If it changes, MAF is bad. But I don't think that is the problem. Lastly, I would check the pre 02 sensors see if they are operating properly. It should go .2 to .8 all the times flucuating within 20-25 sec crosscount. In conclusion, do the modulator first, hopefully you don't have too much carbon build up in your egr passages. After that, the pre 02 sensors. I hope that helps.
Warm the car up before bringing it to a Smog Station ALWAYS.
Warm the car up before bringing it to a Smog Station ALWAYS.