Header Install messing with my computer
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Header Install messing with my computer
I have a 94 F150 5.8L with 185K on it. I recently installed headers and dual exhaust. I left the cat off and removed the smog pump system. The EGR was reinstalled( I added the connection to the EGR from the header) and the O2 sensor relocated to downstream of the collector. I left the connection tubes between the heads but blocked off the main line supplying to them from the smog pump.
The truck runs great most of the time but occasionally it gets into a really rough idle or it will bog down sometimes when I'm driving. It acts like the computer retards the timing for some amount of time and then eventually clears up. I am not getting any CEL or any indication of what the computer is seeing. I need help trouble shooting this issue. Any help would be appreciated.
The truck runs great most of the time but occasionally it gets into a really rough idle or it will bog down sometimes when I'm driving. It acts like the computer retards the timing for some amount of time and then eventually clears up. I am not getting any CEL or any indication of what the computer is seeing. I need help trouble shooting this issue. Any help would be appreciated.
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From: Rio Rancho USA
Fisrt thing, reset the computer and see how it affects the problem. Second, the relocated O2 sensor MIGHT be the culprit, because its not in the same place, it might be getting different readings than the comp thinks it should.
The comp will not throw a CEL on until after 2 consecutive driving cycles with the problem happening both times. Is the problem random, or can you replicate it easily?
The comp will not throw a CEL on until after 2 consecutive driving cycles with the problem happening both times. Is the problem random, or can you replicate it easily?
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Thanks for responding. I can't force the problem to show up but it pretty much happens most every time I drive it. I have cleared the codes. What's weird is that after the initial removal of the smog pump, I got a code acknowledging that the thermactor wasn't working. But after I got that code a couple of times and I reset it, it hasn't come back. It's been two months since I removed it. But the intermittent poor running condition still persists. I'm suspect of the O2 sensor as well but I dont know what I can do about it. There really is no other place to mount it unless I install it in a particular head tube. I've heard that the closer to the collector the better and that's where it's at right now.
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If the O2 sensor was just relocated instead of replaced when you installed the headers I would rec ruling that out first...How many miles on the sensor??? If you rule out the sensor, I would recommend starting with the basics, Air, Spark, and Fuel.
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I just relocated it, not replaced it. It's possible that unthreading it as well as extending the harness for the new location may have pushed it over the edge of proper operation. I will consider replacing it as a check.
Thanks.
Thanks.
