O2 sensor

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Dec 4, 2002 | 09:27 PM

robnooy

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From: grande prairie canada

O2 sensor

Have a 1989 F-150 with 302. Had dual exhaust installed. Cats removed and the O2 sensor replaced into the right side pipe. With the cat gone what will that do to the readings that the O2 is taking.Will it make performance worse or better. I get 11 or so miles per gallon. thanks.

gotta burn gas to make noise

Dec 4, 2002 | 09:35 PM

steve83

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From: Memphis, TN

O2 sensor

The HEGO was before the cats, so it sees the same thing, but it's only seeing the exhaust from one bank of the engine. It may make the computer THINK the engine is running lean, so it may MAKE it run rich, but that's a guess.

Performance will probably drop slightly.

Dec 4, 2002 | 10:37 PM

EPNCSU2006

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From: Concord, NC

O2 sensor

My guess is that the O2 sensor senses the percent oxygen in the exhaust, so theoretically, the percentage should be the same for each side, and if you put them together, only the volume of exhaust would change, while still sensing the same percentage of oxygen.

Dec 5, 2002 | 01:14 AM

mike_v2v98

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From: abbotsford canada

O2 sensor

i did the same on my 95 f150 302
put on dual exhaust with no cats and just left the o2 sensor on one side of the exhaust
my mpg dropped to about 8 or 9
took the truck back and had headers put on with an H pipe and put the o2 sensor in the middle of the h pipe
im back up to about 14 or 15 mpg and alot more throttle responce

not to mention a really cool sounding truck
lol

Dec 5, 2002 | 07:34 AM

EPNCSU2006

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From: Concord, NC

O2 sensor

Just a curiosity question, did you have an h-pipe before you put one in for the O2 sensor?

Dec 8, 2002 | 11:30 AM

robnooy

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From: grande prairie canada

O2 sensor

what would happen if i had the two pipes join into one using a y-pipe and then place the O2 sensor after the y-pipe.
gotta burn gas to make noise

Dec 8, 2002 | 12:02 PM

steve83

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From: Memphis, TN

O2 sensor

That's really what the exhaust shop should have done to begin with. Either the Y-pipe you just described, an X-pipe system, or an H-pipe with the crossover no longer than twice the diameter of the 2 pipes.