no cats
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My truck is born and raised in Canada and it has two O2 sensors on it. Remove the cat, the check engine light comes on, rig goes into limp mode, fuel mixture and milage gets goofed. Take a look under the truck and under the hood. If there is an O2 sensor behind the cat, and one in the exhaust pipe after the manifold, then you have to keep the cat to keep the sensors reading right. I do not know anything about the simulators. I put in a hi-flow cat to get the truck back to normal. Hope this helps.
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From: Bored town OH
hmm. On my door sticker, it said mine was made in canada, but there's only 1 sensor, in the first cat (the 2 into 1 cat). Yours being 8 years newer probobly has something to do woth it. I havent checked for one after the manifold, I'll look into that.
Last edited by Schmids4.9l; Oct 31, 2005 at 10:21 PM.
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bchunter
You have a mass air vehicle.
1996 all models, mass air
1995 earlier, california based trucks went mass air between 92-96 all other states remained speed density until 1996.
speed density = one O2 sensor = no check engine light if cat is modification/removed
mass air = two O2 sensors = check engine light if cat modified or removed.
You have a mass air vehicle.
1996 all models, mass air
1995 earlier, california based trucks went mass air between 92-96 all other states remained speed density until 1996.
speed density = one O2 sensor = no check engine light if cat is modification/removed
mass air = two O2 sensors = check engine light if cat modified or removed.
Last edited by Motorhead351; Nov 1, 2005 at 07:17 AM.
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From: Toronto, ON
Originally Posted by bchunter
I wanted to take the cat out of my truck, but in the 96, there are 2 O2 sensors, one infront of the cat, and one behind, so I had to go the route of a hi-flow cat instead. Put on 3" and a flowmaster 50 delta and it sounds pretty good.
Wha?!!?
on a 96, there should be 3 o2 sensors. one in each header/exhaust manifold, and one between the the 2 cats. as far as i know, the one between the 2 cats is just there to monitor the the first cat, and has NOTHING TO DO with air/fuel ratio.
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I have a 1995 that had two cats, which I cut out and made a tube that brought the two exhausts together made a 4" collector and I run a 4" exhaust pipe out to a new muffler, which is an after market diesel one and it improved my gas mileage by about 20% and I rewelded a nozzle in for my O2 sensor and my truck was made in the 10th month of 1995 and it is a Canadian truck
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I had a '94 F150 I6 (shoulda never got rid of it) and i cut both cats off and run true strait pipes (2") right out the back into some 3.5" chrome echo cans and wow would that thing crackle. It is far and away the loudest motor i have ever heard. if you kept it below about 1750 RPM's it had a real deep roar but if you got it above that it got kinda high pitched but it is VERY unique and i loved it. I noticed a slight top end increase and a slight gas mileage increase.
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From: Toronto, ON
I have a 96 Mass Air OBD-2 Made in Wayne Co. that has 3 o2 sensors. Are you sure there are 96 Mass Air OBD-2 trucks that only have 2 o2 sensors?
I was under the impression that the 3rd o2 sensor in my truck, that is located after the first cat, is just there to monitor that the cat is doing what it's supposed to do. The 2 other o2 sensors are located on each of the exhaust headers.
If one was to remove both cats, then you would get a check engine light with a OBD-2 code saying the cat is defective or non-functioning, but no difference in air/fuel. It would then be easy to install a resistor or a pre-made simulator to kill that CEL.
I was under the impression that the 3rd o2 sensor in my truck, that is located after the first cat, is just there to monitor that the cat is doing what it's supposed to do. The 2 other o2 sensors are located on each of the exhaust headers.
If one was to remove both cats, then you would get a check engine light with a OBD-2 code saying the cat is defective or non-functioning, but no difference in air/fuel. It would then be easy to install a resistor or a pre-made simulator to kill that CEL.
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Originally Posted by Roushians
I have a 96 Mass Air OBD-2 Made in Wayne Co. that has 3 o2 sensors. Are you sure there are 96 Mass Air OBD-2 trucks that only have 2 o2 sensors?
Your also right, people use MIL eliminators to get ride of the check engine light.
I also believe your right in that the third O2 only monitors catalytic converter function, has no role in adjusting air/fuel.
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Interesting. When I looked at mine, I only saw one O2 in one of pipes from one of the manifolds. I will have to look again and see if there is one in the other manifold.
My truck came to me with only one cat on it, I am presuming that the fellow before me took out the second cat all together, and left one hollowed one, which was the reason my check engine light was on.
So, is a mass air vehicle better then the previous style? Or is there more issues I have to be aware of. This mass air stuff is new to me. Thanks for the help.
My truck came to me with only one cat on it, I am presuming that the fellow before me took out the second cat all together, and left one hollowed one, which was the reason my check engine light was on.
So, is a mass air vehicle better then the previous style? Or is there more issues I have to be aware of. This mass air stuff is new to me. Thanks for the help.
