If I were to cut my exhaust off and run a piece of y pipe off my manifolds into a straight pipe to the muffler would the computer go crazy since it wouldnt have the O2 sensors? Would is run different without the O2 sensors?
Straight Pipe vs. Computer
- Thread starter RoverRideAlong
- Start date
what is the point and the advantage of doing this? your time and money would be better spent on cleaning up the heads.
Rob, why are you considering doing this?
Something wrong with your manifolds or existing Y pipe?
Last time we were looking at your motor at Livingston, there was an exhaust bolt broken off (which I thought you were getting fixed) , but that's all I remember wrong with the exhaust.
Something wrong with your manifolds or existing Y pipe?
Last time we were looking at your motor at Livingston, there was an exhaust bolt broken off (which I thought you were getting fixed) , but that's all I remember wrong with the exhaust.
the O2 sensors are used by the computer to calculate the fuel/air ratio. without them, the compy wouldn't know what to do and would probably revert to a limp home map.
andy
andy
M
mistered
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Everyone will not like me for this. My cats are gone....magnaflow at the center location with nothing but pipe going out the back. 1995 disco. I can get away with it in Alabama....no emissions testing here. I do have the o2's still installed. The truck runs great and "without a doubt"has more power. I also have a aftermarket air intake system. So, I ge better air in and out....more power. The truck is alittle louder at highway speeds. No other negative effects at all.
S
Schattenjager
Guest
The two sensor per cat BOSCH system reads the output of the motor and also measures the effectivness of the cats and will adjust fuel mix accordingly. There are ways to trick the system, but really not worth the effort. I have seen some 500+ HP motors run through a cat only, pass emissions, and sound great. Just the cats and pipes - no mufflers. You can also get the high flo cats...
I hate cats - they are the wrong answer to a question that applied to old, carb fed cars.
I hate cats - they are the wrong answer to a question that applied to old, carb fed cars.
Yeah I got those bolts fixed now I have a weld broken off where the down pipe from the manifold on the passenger side to the cat. I am just planning on getting it welded back carefully but thought I would consider options. I wouldnt mind making it louder. I dont give a fuck, it sounds good. I was just curious if i didnt have the O2 sensors if the computer would go crazy. Is there any way of getting around the O2 sensors and the computer?
S
Schattenjager
Guest
I have heard rumors of some d1 owners with gems engines that have gotten ride of there cats without CEL light but that is all I know.
My '96 has no cats, flowmaster, I left the O2 sensors. Check engine light has been on since I bought the truck over 5 years ago. No emissions here in Knoxville yet..
You definitely want to keep the O2 sensors... Without the O2 sensors your truck would probably run in open loop mode and always run rich. You can get 02 simulators to keep it from running so rich and throwing codes, but it still won't be true closed loop.
You could pull the cats, but even if your county/state allows it don't expect it to last forever. My county didn't have emissions testing for the longest time and I thought about pulling mine as well (in my street/racecar). Of course right before I was going to pull them, the law changed. Go figure.
-justin
You could pull the cats, but even if your county/state allows it don't expect it to last forever. My county didn't have emissions testing for the longest time and I thought about pulling mine as well (in my street/racecar). Of course right before I was going to pull them, the law changed. Go figure.
-justin
There is absolutely no reason to do that. There will only be drawbacks, and no benefits. Take it to an exhaust shop, and have it repaired properly, or source a used section from a salvage yard. Alternatively, you can buy the section new.
Cheers,
Kennith
Cheers,
Kennith
kennith said:
X2.
Agree completely.
Not sure if everyone is on the same page when talking about the O2 sensors.
Not sure about the the earlier Discos, but I thougt ALL the later ones had the 4 sensor setup, with 1 set pre cats and 1 set post cats.
The ones pre cat constantly monitor the exhaust gasses and provide a feedback signal needed for closed loop fueling. They are needed so the ECU can make the proper adjustments for air/fuel mixture.
They ones post cat do not affect fueling, but they are there to make sure the cats are doing thier job. That is why people who take them out are getting faults. In the past I had considered taking out the cats and replacing the downstream sensors with simulators, but could never find ones with the 0-5 signal I needed for the Bosch setup. In the end I decided it was just not worth it. I have also read that the cats were not as restrictive (at least properly functioning ones) as I guess I thougt in the past. After verifying proper flow with a pressure gauge, I decided the cats would stay.
Just seems to me the best thing you could do would be a proper repair of what you have.
Peace,
Dan