Downstream O2's and rough running
#1
05-13-2010, 07:06 PM
Join Date: Sep 2009
Location: Small Town, Manitoba
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Downstream O2's and rough running
Hey guys,
Just finished installing the transmission on my 2000 F-150, 4x4, 5.4L a little while ago. I removed the tranny to do the input shaft seal, and did the rear main and transfer case seals while I was there. 4R70W
I've got an issue though...
I am experiencing a rough running and misfire when driving the truck. My down stream O2 sensors are not reading on both banks.
I've checked my connections, but I'm not sure where else to look. With both sensors being out, I'm thinking there is a common problem between the two, possibly the ground.
What do you think?
Thanks.
Just finished installing the transmission on my 2000 F-150, 4x4, 5.4L a little while ago. I removed the tranny to do the input shaft seal, and did the rear main and transfer case seals while I was there. 4R70W
I've got an issue though...
I am experiencing a rough running and misfire when driving the truck. My down stream O2 sensors are not reading on both banks.
I've checked my connections, but I'm not sure where else to look. With both sensors being out, I'm thinking there is a common problem between the two, possibly the ground.
What do you think?
Thanks.
#3
05-15-2010, 11:35 AM
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Join Date: May 2010
Location: Central FL
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someone stole my catalytic converters a while back and took the 02 sensors with them. I just welded in new cats and said to hell with the 02 sensors because when both banks dont read right the computer automatically sets to a predetermined tune to run without them. The truck runs fine and has for a few months now, however I do plan on fixing that in the coming weeks just to be sure. But projectSHO is right, it shouldnt cause drivability issues. And I think that you might be looking in the right direction with there being a common problem between the two, instead of them both just going out at the same time.
#4
05-16-2010, 05:00 AM
I waited for awhile to see other replies before adding one.
What do you mean 'no readings' on the rear sensors?
I asked because you need to know what to expect from them before deciding they are not functioning.
They will not swing in output like the fronts do.
Their outputs will only change over a small range with time.
You can see this with a scanner set to observe live data while the engine is running.
Reason is they are there to provide a ratio of switching info to the front sensor as a means of logic decision, as a basis for determining the relitive health of the cat or it's ability to store oxygen.
If this switch ratio goes out of limits you will get a code set and a CEL lamp.
It will not affect the drivablity or cause a miss because it's only a monitor to indicate the relitive health of the cat on each bank.
Your miss is some other issue.
What do you mean 'no readings' on the rear sensors?
I asked because you need to know what to expect from them before deciding they are not functioning.
They will not swing in output like the fronts do.
Their outputs will only change over a small range with time.
You can see this with a scanner set to observe live data while the engine is running.
Reason is they are there to provide a ratio of switching info to the front sensor as a means of logic decision, as a basis for determining the relitive health of the cat or it's ability to store oxygen.
If this switch ratio goes out of limits you will get a code set and a CEL lamp.
It will not affect the drivablity or cause a miss because it's only a monitor to indicate the relitive health of the cat on each bank.
Your miss is some other issue.
#5
05-16-2010, 11:30 AM
someone stole my catalytic converters a while back and took the 02 sensors with them. I just welded in new cats and said to hell with the 02 sensors because when both banks dont read right the computer automatically sets to a predetermined tune to run without them. The truck runs fine and has for a few months now, however I do plan on fixing that in the coming weeks just to be sure. But projectSHO is right, it shouldnt cause drivability issues. And I think that you might be looking in the right direction with there being a common problem between the two, instead of them both just going out at the same time.