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Unread 06-02-2012, 07:42 AM   #16
rm2001wj
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Components of lacquer thinner vary somewhat depending on the manufacturer. Here is a list for a typical thinner: Toluene, Acetone, Isopropyl Alcohol, Methyl Ethyl Ketone, Propylene Glycol Methyl Ester Acetate. All of these chemicals burn just like gasoline, need less oxygen than gasoline, and have the same combustion products as gasoline. After combustion there is nothing left of the thinner that can do any more for the converter than the burned gasoline.

That goofy guy in the video makes up stuff, like what the thinner can do, and that the cat is still 95% efficient when the P0420 code is thrown. Always keep in mind that this is the internet, and people can make nonsense claims like those in the video and naive people will believe it and also pass it on to others.

Sure you can say try and see what happens. However, one gallon of lacquer thinner in 10 gallons of gas is a pretty strong concentration of a powerful solvent. I would worry about what might happen to any plastic or rubber parts in the fuel system.

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Unread 06-02-2012, 12:57 PM   #17
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Quote:
Originally Posted by rm2001wj View Post
Components of lacquer thinner vary somewhat depending on the manufacturer. Here is a list for a typical thinner: Toluene, Acetone, Isopropyl Alcohol, Methyl Ethyl Ketone, Propylene Glycol Methyl Ester Acetate. All of these chemicals burn just like gasoline, need less oxygen than gasoline, and have the same combustion products as gasoline. After combustion there is nothing left of the thinner that can do any more for the converter than the burned gasoline.

That goofy guy in the video makes up stuff, like what the thinner can do, and that the cat is still 95% efficient when the P0420 code is thrown. Always keep in mind that this is the internet, and people can make nonsense claims like those in the video and naive people will believe it and also pass it on to others.

Sure you can say try and see what happens. However, one gallon of lacquer thinner in 10 gallons of gas is a pretty strong concentration of a powerful solvent. I would worry about what might happen to any plastic or rubber parts in the fuel system.

I like this answer....I would never just pour something into my gas tank without knowing what it is made up of or not knowing what effects it might have. I'd rather spend the extra $$ on the cats and know there new and hope that it takes care of my problem. Thanks for all the replies and would like to see more responses.
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Unread 06-02-2012, 01:25 PM   #18
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I stumbled on this thread by accident, but I'm glad I did. My Jeep is a ZJ with the 4.0L, single cat. I've been getting the PO420 code for the last couple months and like the OP, have read so much info my head is spinning.

In April I had a new muffler and tailpipe installed and since that time I've been getting the code. A month prior to that the local Jeep dealer did corrected some recall issues and one of those was to inspect and replace the cat if necessary. My cat checked out fine. I'm taking it that an O2 sensor failure won't throw the 420 code, but I'm wondering if the sensor connection has been loosened when the shop replaced the muffler. I've noticed no performance issues when it throws the code.

Would a bad electrical connection at the O2 sensor give the 420 code or would that be a different code entirely? Any ideas?
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Unread 06-02-2012, 08:33 PM   #19
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Quote:
Originally Posted by platinum5.9
I have been dealing with the dreaded p0420 code in my 03 Grand for some time now. Its a 4.7 ho with the two mini precats, full size Magnaflow cat and 4 O2 sensors. I have read numerous articles that say its the drivers side top O2 sensor, some that say the pre-cats need replaced, and some that say it could be caused by a exhaust leak causing the O2 to read incorrect. I need input from people that have had the issues and managed to correct them and people who maybe do this for a living and have more knowledge than me and the mechanics in this small town. NYS inspection it has arrived and I need to get this thing to pass inspection. Any help would be great and Thank you in advance.
Do you know a repair shop well enough to get it inspected?

Best regards,
Nick
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Unread 06-02-2012, 08:53 PM   #20
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Quote:
Originally Posted by rm2001wj View Post
Components of lacquer thinner vary somewhat depending on the manufacturer. Here is a list for a typical thinner: Toluene, Acetone, Isopropyl Alcohol, Methyl Ethyl Ketone, Propylene Glycol Methyl Ester Acetate. All of these chemicals burn just like gasoline, need less oxygen than gasoline, and have the same combustion products as gasoline. After combustion there is nothing left of the thinner that can do any more for the converter than the burned gasoline.

That goofy guy in the video makes up stuff, like what the thinner can do, and that the cat is still 95% efficient when the P0420 code is thrown. Always keep in mind that this is the internet, and people can make nonsense claims like those in the video and naive people will believe it and also pass it on to others.

Sure you can say try and see what happens. However, one gallon of lacquer thinner in 10 gallons of gas is a pretty strong concentration of a powerful solvent. I would worry about what might happen to any plastic or rubber parts in the fuel system.
Sorry, but those components you listed will NOT burn just like Gasoline. Does E-85 burn just like gas... NO. Does Gas with 10% Ethanol burn just like Gas?? NO. They all effect the exhaust gas significantly.
Sorry but the resultant gases from the thinner are going to change the output gas, one assumes that it is one of these gases, that cleans the cat. Also could be a temperature thing... if you raise the temp in the cat, it will burn off material that has accumulated in the honeycomb structure. My Semi Truck uses as similar principle to clean the diesel particulate filter. Injecting fuel into the honeycomb to raise the temp to over 1200F converting the soot to CO2. 2011 and new trucks take this even farther injecting aqueous urea solution after the DPF lowering Nox gasses to almost nothing.

Several other post have mentioned that a small drop in efficiency can cause this code to be thrown.. so it's not just this "goofy" guy that has claimed that. And someone else said this procedure worked for them in their Jeep.

Lastly I am FAR from Naive... I am just trying to help the OP to not spend Serious money on new cats, when he could try something else first. It's certainly his decision to make.. and it appears from his last post here that he has chosen to buy new cats.. fine. But at least he has made that decision knowing there ARE other possibilities.

As a long time car repair guy.. You NEVER start a repair buy simply replacing parts, unless you can VERIFY that the part is in fact bad. Or if the part happens to be inexpensive, and easy to replace. Or if it's the only way to diagnose the problem.

Anyway... good luck to the OP.. Hope you get it fixed.
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Unread 06-03-2012, 03:27 AM   #21
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If you water wash the engine with a fine mist of water from a garden hose nozzle the slight misfire will elevate the cat temp and the water vapor in the exhaust will help control the temp to keep it from getting too hot.

I need to do this on my oil using 1996 Saturn to decarbon it, and at 186,800 miles it still has the Original cat.

Toluene is a great octane improver
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Unread 06-03-2012, 10:15 AM   #22
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Very interesting info guys. Its not that I do not believe you, its that I can get magnaflow mini replacement cats for around $85 ea which I do not think is a bad price. I've talked to a few guys that have been doing this for years and they seem to think that a pre-cat replacement will take care of this problem. I welcome all info and suggestions. Thanks again guys...
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Unread 06-03-2012, 02:04 PM   #23
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Quote:
Originally Posted by kens97sto171 View Post
Sorry, but those components you listed will NOT burn just like Gasoline. Does E-85 burn just like gas... NO. Does Gas with 10% Ethanol burn just like Gas?? NO. They all effect the exhaust gas significantly.

.........
As a long time "car repair guy" you should know that when organic compounds are burned in the combustion chamber, the combustion products (exhaust gases) consists of NOx, H2O, CO, CO2 and usually a little partially burned HC. The components of lacquer thinner along with gasoline (which is composed of several different organic compounds), E10, and E85 all burn in the combustion chamber producing the same exhaust gases. The difference between them would be in the proportions of the various exhaust gases. That is what is meant by saying that the components burn just like gasoline. It might be worth while it you looked up the composition of pump gasoline. You would be surprised at the number of organic components and additives. Gasoline is by no means a single compound and mixing ethanol (E10 and E85) or lacquer thinner with it can change the proportions of the various combustion products, but not the products themselves. There is no magic compound produced in the combustion chamber that will do anything to improve catalytic converter efficiency.

Quote:
Several other post have mentioned that a small drop in efficiency can cause this code to be thrown.. so it's not just this "goofy" guy that has claimed that. And someone else said this procedure worked for them in their Jeep.
A internet search for sources of the 95% efficiency stuff lead only to the "goofy" guy on the video. Surely if it were true, there would be a more reliable source somewhere.
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Unread 06-03-2012, 05:26 PM   #24
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found this decent article that tells u the usual percent thresholds and as far as the goofy guy, idk if someone miss quoted him or he said it wrong, but the 95 percent efficiency threshold isnt exhaust flow, its emissions reduction, but a clogged or dirty cat could very easily not reduce emissions enough and fall below the threshold, and with vehicles getting more and more epa regulated, the thresholds are rising every year, oh and as far as the cat no being able to be cleaned by changing the type of fuel burned, just read any article about how a cat actually works and it will explain that a cat actually changes the types of gases being released, and in a 1% change in O2 can rise the cats internal temp by 100 degrees, so putting in a cleaner burning fuel can easily rise the cats operating temp by 200-500 degrees, in doing so it more completely burns any carbon or other contaminants, such as silicone (from seals and gaskets), and unburnt fuel (rich condition) are the biggest killers of cats, just thought id try to clear up the confusion a little, http://www.brakeandfrontend.com/Arti...onverters.aspx
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Unread 01-27-2013, 06:48 AM   #25
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I replaced the 2 mini cats with magna flow replacements and the light has been off ever since. The original cats did show signs of wear. The honeycomb was burnt out inside.
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Unread 04-09-2013, 09:37 AM   #26
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Platinum, is yours 50 state?
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Unread 04-09-2013, 10:05 AM   #27
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Platinum, is yours 50 state?
That's a great question..... i am not sure but don't think so. Not without muffler and three high flow cats
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Unread 04-09-2013, 10:16 AM   #28
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I have the 50 state emissions I already have the kolak exhaust and I need new precats. I'm wondering if the magnaflow precats will still trigger the light due mine being 50 state if you get a chance could you take a look on the inside of your and see of it says federal 49 or 50 state including cali
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Unread 04-09-2013, 10:37 AM   #29
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Beginning in 2001, all WJs left the factory 50 state legal. It was the 1999 and 2000 models that could be federal (49 state I guess) or 50 state (49 state plus CA).
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Unread 04-09-2013, 11:10 AM   #30
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It wouldn't surprise me if a continuous long highway drive, or sustained 2500+ RPM for half an hour would clean the heck out of your catalyst with ordinary gasoline - same way a self cleaning oven works. Everyone drives differently, I could imagine a short trip, low RPM lifestyle could lead to crusty cats once in a while.

No universal band-aid obviously, a cat whose problem is something other than crust would not be able to benefit from such a thing.
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