Cat Cleaning Citric & Oxalic Acid. CO Emissions
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- #22
Yes, there was still IsoHeet in the gas. Denatured and gas combo was long gone. It was only 3 bottles for 1/3 of tank (8 +/- gal) so its not much.
If the alcohol did the lowering then I would of thought that my numbers would of been lower with the denatured alcohol.
I think most of the alcohol was gone as I didn't smell the alcohol fumes in the exhaust during this test or in the garage. I can smell when there is more alcohol in the gas ie, cheap gas in the tank CitiMarket gas make my 80 exhaust stink bad). My 80 doesnt like cheap gas, there is an alcohol smell in the fumes that is over powering. I smelt the alcohol fumes when I did the last fail test with IsoHeet. This "Pass test" had the IsoHeet in it but the smell was not present last night when I parked the 80, it wasn't there this morning or before and after the test (while waiting in line). But that doesn't mean it didnt make didnt make a difference.
If the alcohol did the lowering then I would of thought that my numbers would of been lower with the denatured alcohol.
I think most of the alcohol was gone as I didn't smell the alcohol fumes in the exhaust during this test or in the garage. I can smell when there is more alcohol in the gas ie, cheap gas in the tank CitiMarket gas make my 80 exhaust stink bad). My 80 doesnt like cheap gas, there is an alcohol smell in the fumes that is over powering. I smelt the alcohol fumes when I did the last fail test with IsoHeet. This "Pass test" had the IsoHeet in it but the smell was not present last night when I parked the 80, it wasn't there this morning or before and after the test (while waiting in line). But that doesn't mean it didnt make didnt make a difference.
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How far off was the timing before you set it to factory?
Which by the way is part of the smog check. Its supposed to be at the factory timing before you can even do the smog test.
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- #25
It was at factory (just a hair under 3 deg) for all but one test. All the test results posted here except this one were at factory setting. Just wanted to see if retarding and adding IsoHeet would have any affect. Timing was about -4 or -5.
It was the 4th test.
HC 1.7954 2 max Pass
CO 43.8013 20 max FAIL
CO2 659.0092
NOx 3.2671 4 max Pass
With my mileage, I assume that there may be timing chain slack so it may or may not be at factory 3 deg timing. Last time is set it, it was right at 3 deg and now its a hair under 3 deg.
It was the 4th test.
HC 1.7954 2 max Pass
CO 43.8013 20 max FAIL
CO2 659.0092
NOx 3.2671 4 max Pass
With my mileage, I assume that there may be timing chain slack so it may or may not be at factory 3 deg timing. Last time is set it, it was right at 3 deg and now its a hair under 3 deg.
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- Thread starter
- #26
My final conclusion is there are way too many variables to conclude that any one thing fix or made my 80 pass.
Most being is the test its self.
In Colorado, they use a dyno to do the emissions test. The emissions tech (they always have a help wanted sign posted) drives the vehicle on the dyno while he/she watches a monitor guiding them to increase or decrease speed of vehicle. Speeds go up (20 mph) then down a little, then up(20 mph), down, slow increase then a steady speed (30 mpg) then a sudden drop to 0. Then a fast up down (30 mpg) the all the way up to 55 mph then a fast drop to 0. (the 80 with worn mud tyres sounds like a tornado going 55 mph on the treadmill)
My feelings is, if the tech is hard or soft with the gas peddle, it should have an affect on the emissions test but that is just a guess. You can watch the monitor and see when the tech is going too fast or too slow as the monitor will tell the tech to increase or decrease speed.
I also feel that the time of day and weather conditions can affect the test.
So of you fail and are very close, try testing at a different location or try doing it at different time of day. It may not make a difference but who knows, you may pass.
From Clean Air CO
Vehicle Variability
My vehicle failed its first emissions test. It passed a second test without getting any repairs. What gives? Is the testing equipment faulty? Are the test drivers to blame?
This situation is of concern to motorists, to the State of Colorado and to Envirotest Systems. Variable test results occasionally occur.
Test Lane Consistency
The emissions testing equipment is standardized in all of the I/M 240 emissions testing lanes. Each test lane self-checks every two hours. If this check reveals a problem with lane calibrations, the lane automatically shuts down, preventing inaccurate testing. In addition, computer software controls the dynamometer testing. The test driver cannot exert more than a marginal influence on the test results.
Vehicles are Variable
Variable test results are generally caused by the vehicle itself, and can happen for a number of reasons. The catalytic converter may not have been adequately preconditioned, or warmed up, for the first test. Driving a vehicle for at least 15 minutes or so to bring it up to operating temperature before taking it in for an emissions test is recommended, as cold vehicles emit a higher level of pollution. The vehicle may have switches and sensors that may be causing problems intermittently. This can be a particular problem with computer-controlled vehicles, and certainly can be a frustrating problem for repair technicians to diagnose.
Small differences in test results from test to test are normal for vehicles, particularly those that are computer-controlled. But if the vehicle is close to the pollution limits to begin with, a small difference in the test result can make the difference in failing or passing the emissions test.
The I/M 240 dynamometer test is very comprehensive. The vehicle is placed on the dynamometer, and the pollution emitted from the vehicle as it simulates driving down the road, accelerating, decelerating, and cruising is collected and analyzed. The idle test detects the pollution emitted only while a vehicle idles. Therefore, the I/M 240 test is much more likely than the idle test to detect an intermittent problem.
Intermittent Problems Can be Pain to Diagnose
Solving these intermittent vehicle problems sometimes requires real detective work by repair technicians. This is one of the reasons vehicle repair has become a much more high-tech business than it formerly was, and why continuing technician training is key to a repair shop's success. It is also why a diagnostic fee is a good investment.
The state is concerned about vehicle variability because a vehicle that manages to pass the emissions test but still goes unrepaired continues to pollute significantly more than it should. The Colorado Air Pollution Control Division maintains several Emissions Technical Centers around the Denver-Boulder area for the purpose of helping motorists diagnose difficult vehicle emissions problems. They may be contacted at 303-744-2442 (and press 3) for information or an appointment.
Most being is the test its self.
In Colorado, they use a dyno to do the emissions test. The emissions tech (they always have a help wanted sign posted) drives the vehicle on the dyno while he/she watches a monitor guiding them to increase or decrease speed of vehicle. Speeds go up (20 mph) then down a little, then up(20 mph), down, slow increase then a steady speed (30 mpg) then a sudden drop to 0. Then a fast up down (30 mpg) the all the way up to 55 mph then a fast drop to 0. (the 80 with worn mud tyres sounds like a tornado going 55 mph on the treadmill)
My feelings is, if the tech is hard or soft with the gas peddle, it should have an affect on the emissions test but that is just a guess. You can watch the monitor and see when the tech is going too fast or too slow as the monitor will tell the tech to increase or decrease speed.
I also feel that the time of day and weather conditions can affect the test.
So of you fail and are very close, try testing at a different location or try doing it at different time of day. It may not make a difference but who knows, you may pass.
From Clean Air CO
Vehicle Variability
My vehicle failed its first emissions test. It passed a second test without getting any repairs. What gives? Is the testing equipment faulty? Are the test drivers to blame?
This situation is of concern to motorists, to the State of Colorado and to Envirotest Systems. Variable test results occasionally occur.
Test Lane Consistency
The emissions testing equipment is standardized in all of the I/M 240 emissions testing lanes. Each test lane self-checks every two hours. If this check reveals a problem with lane calibrations, the lane automatically shuts down, preventing inaccurate testing. In addition, computer software controls the dynamometer testing. The test driver cannot exert more than a marginal influence on the test results.
Vehicles are Variable
Variable test results are generally caused by the vehicle itself, and can happen for a number of reasons. The catalytic converter may not have been adequately preconditioned, or warmed up, for the first test. Driving a vehicle for at least 15 minutes or so to bring it up to operating temperature before taking it in for an emissions test is recommended, as cold vehicles emit a higher level of pollution. The vehicle may have switches and sensors that may be causing problems intermittently. This can be a particular problem with computer-controlled vehicles, and certainly can be a frustrating problem for repair technicians to diagnose.
Small differences in test results from test to test are normal for vehicles, particularly those that are computer-controlled. But if the vehicle is close to the pollution limits to begin with, a small difference in the test result can make the difference in failing or passing the emissions test.
The I/M 240 dynamometer test is very comprehensive. The vehicle is placed on the dynamometer, and the pollution emitted from the vehicle as it simulates driving down the road, accelerating, decelerating, and cruising is collected and analyzed. The idle test detects the pollution emitted only while a vehicle idles. Therefore, the I/M 240 test is much more likely than the idle test to detect an intermittent problem.
Intermittent Problems Can be Pain to Diagnose
Solving these intermittent vehicle problems sometimes requires real detective work by repair technicians. This is one of the reasons vehicle repair has become a much more high-tech business than it formerly was, and why continuing technician training is key to a repair shop's success. It is also why a diagnostic fee is a good investment.
The state is concerned about vehicle variability because a vehicle that manages to pass the emissions test but still goes unrepaired continues to pollute significantly more than it should. The Colorado Air Pollution Control Division maintains several Emissions Technical Centers around the Denver-Boulder area for the purpose of helping motorists diagnose difficult vehicle emissions problems. They may be contacted at 303-744-2442 (and press 3) for information or an appointment.
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- Thread starter
- #27
Cats are in the cooker again along with the O2's.
This time I will just run a can of BB44K through a tank of gas after installing the cats/O2's. I wont do any other changes to the 80
till after the next emission test. I want to see if there are really any changes to the cats/O2.My thinking is that as there is no agitation or flowing for the solution so the crud on the cats needs to be burned off.
My CEL was not on but I did have Code 25 26 when I replaced the CEL bulb. The computer has not been reset scene at least last summer.
I normally get Code 25 26 when I do a lot of city driving. It goes away with all hwy driving. I changed from Rotella T6 to Chevron 400 15w40 or now Chevron 400 LE Syn 5w40.
This time I will just run a can of BB44K through a tank of gas after installing the cats/O2's. I wont do any other changes to the 80
till after the next emission test. I want to see if there are really any changes to the cats/O2.My thinking is that as there is no agitation or flowing for the solution so the crud on the cats needs to be burned off.
My CEL was not on but I did have Code 25 26 when I replaced the CEL bulb. The computer has not been reset scene at least last summer.
I normally get Code 25 26 when I do a lot of city driving. It goes away with all hwy driving. I changed from Rotella T6 to Chevron 400 15w40 or now Chevron 400 LE Syn 5w40.
Good luck. I'm sure you've read it elsewhere, but just in case: get the cats good and hot on a highway lap. Turn off O/D, and turn on PWR. I proved this when my wife tested our last Cruiser. It went in cold with O/D on, and missed NOX. I did nothing but what I listed above, and it passed with less than 2 for NOX.
- Thread starter
- #30
Cats are done cleaning. Left the cats in for 11 hrs, instructions say 8 hrs. The buildup is still on cat in the place that had heavy buildup.
It looks like Silly Putty. Took a screwdriver to it is soft. Not sure if it will burn off or bake back on. I see now why
its said to use flowing solution. Some people have modified a dishwasher so the jet action sprays off the crud.
I see now that maybe after cleaning the cats I didn't pass first test. Maybe the softened crud burned off by the second test.
I will take the cats to the car wash and see if it will spray off.
It looks like Silly Putty. Took a screwdriver to it is soft. Not sure if it will burn off or bake back on. I see now why
its said to use flowing solution. Some people have modified a dishwasher so the jet action sprays off the crud.
I see now that maybe after cleaning the cats I didn't pass first test. Maybe the softened crud burned off by the second test.
I will take the cats to the car wash and see if it will spray off.
- Thread starter
- #31
After driving a few miles and removing the cats again to seal up the reused for a second time cat gaskets with high temp exhaust sealant, I looked in the cat and saw that the crud that didn't get removed from the soaking and hosed them off with garden hose was removed with the little driving I did.
I added a can of BG44K and will burn up that gas and have it emission tested to see if the cats and O2's have any life left in them.
So far the CEL didn't turn on but it was not one before the cleaning. Its gong to be below 30 high till next weekend where it will be back to 50's. Not sure if testing when its that cold will alter my test results as it was in the 50's for the other tests.
One other problem is my oil has 1700 mi on it. I had to add a qt at 1500 mi. When the oil gets this many miles in it, it starts to use it at a faster rate thus more oil will be burning through the motor and that should affect emission test in a negative way.
I added a can of BG44K and will burn up that gas and have it emission tested to see if the cats and O2's have any life left in them.
So far the CEL didn't turn on but it was not one before the cleaning. Its gong to be below 30 high till next weekend where it will be back to 50's. Not sure if testing when its that cold will alter my test results as it was in the 50's for the other tests.
One other problem is my oil has 1700 mi on it. I had to add a qt at 1500 mi. When the oil gets this many miles in it, it starts to use it at a faster rate thus more oil will be burning through the motor and that should affect emission test in a negative way.
This is an old thread, but just for the record, oxalic acid is not highly toxic.
It occurs naturally in many foods - chives, parsley, swiss chard, rhubarb, etc.
That said, in concentrated form, it becomes toxic to ingest, and it's a pretty strong acid, so treat it with some respect.
But, it's a nice stable crystalline powder that comes in a little plastic jar - no big deal.
You can handle it safely with an ordinary stainless steel table spoon.
No hazmat suit needed. Maybe safety goggles & rubber gloves?
Pretty much the same for citric acid too, but oxalic is the stronger acid, FYI.
Has anyone tried 1 gallon of lacquer in the gas tank, gas tank 1/2 full, then driving ~150 miles and if so does this work? Is it dangerous for the engine? Thanks
Yes, I did that. No problems at all with engine power or drive-ability (ran it hard)- BUT - also not one iota of change or improvement.
(the car was a '99 Lexus GS300, which has one rolled corrugated metal core CAT for each of the front 3 and back 3 cylinders, and an upstream O2 sensor before each, etc.
This makes perfect sense - from the perspective of physical & chemical changes that it could bring. (nothing)
Doing that is no more or less than running higher Octane fuel, which simply burns in a more stable way with less chance of spontaneous explosive ignition.
If it ignites in the cylinder and burns properly with a reasonably balanced amount of oxygen - then burnt exhaust gas is still what reaches the CATs.
Well - it does cycle back and forth between - a little rich - a little lean, on and on.
The problem you are dealing with is a thin layer of ash, coating the catalytic metals, due to age, not some kind of burnable organic coating.
(the car was a '99 Lexus GS300, which has one rolled corrugated metal core CAT for each of the front 3 and back 3 cylinders, and an upstream O2 sensor before each, etc.
This makes perfect sense - from the perspective of physical & chemical changes that it could bring. (nothing)
Doing that is no more or less than running higher Octane fuel, which simply burns in a more stable way with less chance of spontaneous explosive ignition.
If it ignites in the cylinder and burns properly with a reasonably balanced amount of oxygen - then burnt exhaust gas is still what reaches the CATs.
Well - it does cycle back and forth between - a little rich - a little lean, on and on.
The problem you are dealing with is a thin layer of ash, coating the catalytic metals, due to age, not some kind of burnable organic coating.
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