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2002 Sienna XLE
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25 Posts
Discussion Starter #1 (Edited)
Friends, what should I do, my '94 Corolla DX 1.8L with 300K+ from Maryland failed CO only in California. Recently I put a new Catalytic converter, Timing set, radiator, water pump, thermostat, some new vacuum hoses and distributor. After the CO failed I put a new OS sensor and coolant temperature sensor and OH! some Castrol stuff to make the oil thicker then retested only to fail Nox only. Am I wrong to feel suspicious that the technician stuck a wood dutch shoe under my hood? This engine does not have an EGR.
 

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Weazler
94 Corolla Base
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903 Posts
Being that its a 1.8, what's your oil consumption like? At 300k you'd have to be burning oil, unless it's already been rebuilt. This motor is notorious for bad oil rings. This could be a factor.
 

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2002 Sienna XLE
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25 Posts
Discussion Starter #3
OH, Yeah! She burn oil. About a quart a month. But that don't change in one month. I don't have the paper from the first test to compare the Nox levels of test one and two.
 

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1997 Corolla
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5,662 Posts
If the oil is old and gassy smelling, then change it, and try again.
 

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Weazler
94 Corolla Base
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903 Posts
I know absolutely nothing about emissions testing. But I'm pretty sure burning that amount of oil is going to put some pretty nasty stuff out of the tail pipe.
 

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Senior TN Member
Porsche
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7,508 Posts
Post the actual emissions results you got. Both the most recent and the earlier one if you can find it. Call up the shop that did the 1st test and get a copy. Or have them read off the results over the phone. The difference between the two will help determine the path to take.

To pass this, I'd recommend the following:

1. retard ignition to max allowed, I think it's 8-degrees or so. This lowers combustion temps and lowers NOx.

2. do IAT and/or engine-coolant temp and/or MAP sensor resistor mod to richen mixture. This also lowers temps and reduces NOx. Depends upon how much leeway you have with HC. Bring it up to just under limit will help reduce NOx by roughly same amount.

3. make a folder documenting everything you do to the car. Very useful for spotting trends over the years.
 

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2002 Sienna XLE
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25 Posts
Discussion Starter #8
Post the actual emissions results you got. Both the most recent and the earlier one if you can find it. Call up the shop that did the 1st test and get a copy. Or have them read off the results over the phone. The difference between the two will help determine the path to take.

To pass this, I'd recommend the following:

1. retard ignition to max allowed, I think it's 8-degrees or so. This lowers combustion temps and lowers NOx.

2. do IAT and/or engine-coolant temp and/or MAP sensor resistor mod to richen mixture. This also lowers temps and reduces NOx. Depends upon how much leeway you have with HC. Bring it up to just under limit will help reduce NOx by roughly same amount.

3. make a folder documenting everything you do to the car. Very useful for spotting trends over the years.
I just discovered something, I did not have theTE1 and E1 shorted while setting the timing. . . . . My timing has been wrong for eight years.
 

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Just play along....
corolla
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3,384 Posts
Oil burning does not seem to affect emission testing, even though it should. Anyone remember the early Dodge minivans? Their Mitsubishi engines smoked like crazy from dropped valve guides but after the smoke cleared in the test facility they passed!

-SP
 

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Senior TN Member
Porsche
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7,508 Posts
Oil isn't reactive enough in the atmosphere to cause issues. It's not monitored by the smog-test sniffer.

However, oil going through the cat will clog it, cause overheating and reduce the cat's life. Then you'll fail the CO/NOx, and perhaps even the HC.

With CA's Nazi-like regulations, it's an extortion racket. We end up paying 2-4x more for "CARB approved" equipment than outside of CA. Many of the replacement-cats have the exact same innards as their 49-state versions. Just that the "CARB approved" ones have been tested and gotten EO# stamped on them. For the exact same part, we have to pay 2-4x more! grr.r...
 

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Senior TN Member
Porsche
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I just discovered something, I did not have theTE1 and E1 shorted while setting the timing. . . . . My timing has been wrong for eight years.
It's within limits though, or else you'll fail the inspection. I think around 14-15 degrees BTDC and you'll get flagged. Best to set it on as low as possible on the allowed range.

Interesting thing is that the cat is a 2ndary combustion-chamber. In certain cases, things don't work as they should. For example, if have high HC, that should lower combustion-temps and NOx right? Yes, but only in the engine cylinders. When that high HC mixture makes it to the cat, it's re-burned using stored O2 in the cat to remove the HC. This extra combustion can be very hot if you've got high HC, and this heat then increases the NOx emissions coming out of the cat.
 

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1997 Corolla
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4,591 Posts
Uh........? I did Fail the inspection.
I think he meant the ignition timing (not the emissions) is within whatever legal limits apply for your engine. I'm not sure if they actually check the timing on your model year in your state.

Without TE1 and E1 jumped the ignition timing will fluctuate between 5-15 BTDC, so I'm curious what it was actually set at when you check it with TE1-E1 jumped.
 

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Senior TN Member
Porsche
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7,508 Posts
I think he meant the ignition timing (not the emissions) is within whatever legal limits apply for your engine. I'm not sure if they actually check the timing on your model year in your state.
They do check ignition-timing in Cali. My wife's '94 DX failed with ignition-timing set at 15-degrees BTDC in 2008 and 2010. Although I find that awfully suspicious as it was supposedly "fixed" in 2008 and pass the 2nd time. These were the years she took it in by herself without me. Not sure how the distributor could've moved by itself... hmmm.....
 

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1997 Corolla
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5,662 Posts
Wow, they actually get a light and check your timing?:facepalm:

They were doing sniffer tests here for a while. The facilities still stand - a true waste of dyno-rollers...
 

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1997 Corolla
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I used to live in CA, and my car is CA. I don't remember them ever using a timing light during the smog test, and there's no way to check it otherwise. I think they hook something to the spark plug wire to measure RPMs. Perhaps, they check the idle RPMs and timing at the beginning before putting it on the dyno. I can't remember at this point.

A funny thing is the previous owner of my car had the timing belt changed 8,000 miles before I bought it. I have the receipt. So I never checked the timing, assuming the pro had checked it after the timing belt change. It ended up being off by 3-5 degrees, and I wondered why it would ping so much. :facepalm:
 
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