bad oxygen sensor
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bad oxygen sensor
I have a 1994 5.8, would this cause you vehicle to have really bad gas mileage,I noticed the tailpipe is aweful black, I don't think its ever been changed, based on all the other poor maintanence thats been done on this truck, I just bought it a couple weeks back and it would appear that this guy has done absolutely nothing to this truck in 10 yrs, it seems to run not bad, but does seem to lack power and really goes through the fuel, thanks Randy
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From: WA
The O2 sensor can either tell your engine to run rich or lean when it goes bad, which can cause bad gas mileage. They need to be replaced about every 50,000 miles so it would probably be a good idea to replace.
Post Fiend
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From: Topsfield, MA
Moved to appropriate forum.
Omni, please take time and put your threads in the correct forum, I've e-mailed you about this and got no response. This is probably the 5th thread of yours in the last two weeks I've moved...you've been on this site for a long time, please be wise about where you place your threads. This thread belongs in the 87-96 forum because it's specific to your truck. The General Automotive forum is for questions/discussions that don't already have a forum for them.
I would check the computer codes based on the instructions from fordfuelinjection.com.
Are you getting smoke out the exhaust? Or did you just notice it on the inside of the pipe...If smoke out the exhaust, it's either running rich or it's burning oil pretty bad. Do you have to add much oil between changes? How many miles on the vehicle? What do you get specifically for mileage? When's the last time you did a tune-up? Have you inspected the plugs for an indication of how your engine is running? The plugs will tell you if it's running rich or lean by their color.
The more infomation you give us the more we're able to help you
Omni, please take time and put your threads in the correct forum, I've e-mailed you about this and got no response. This is probably the 5th thread of yours in the last two weeks I've moved...you've been on this site for a long time, please be wise about where you place your threads. This thread belongs in the 87-96 forum because it's specific to your truck. The General Automotive forum is for questions/discussions that don't already have a forum for them.
I would check the computer codes based on the instructions from fordfuelinjection.com.
Are you getting smoke out the exhaust? Or did you just notice it on the inside of the pipe...If smoke out the exhaust, it's either running rich or it's burning oil pretty bad. Do you have to add much oil between changes? How many miles on the vehicle? What do you get specifically for mileage? When's the last time you did a tune-up? Have you inspected the plugs for an indication of how your engine is running? The plugs will tell you if it's running rich or lean by their color.
The more infomation you give us the more we're able to help you
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not quite sure about the posting thing Justin, every thread I post it is specific to my truck, If oxygen sensors, go here and not in the electrical forum, than why not my posts on leveling springs, front hubs,etc. I don't post unless its about my truck which is a 1994 f150, am I missing something here.
Post Fiend
Joined: Nov 2001
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From: Topsfield, MA
It's fine to post about your truck, but you posted this oxygen sensor (specific to your truck) question in the General Automotive forum. It belongs in the 87-96 forum as the General Automotive forum is for General topics about automotive discussion, not a specific question regarding your F-150.
This thread doesn't belong in the electrical forum because the 02 sensors are specific to the engine/truck. The wiring/electrical forum doesn't discuss o2 sensors (just general wiring).
A leveling spring thread is a GENERAL suspension question, not specific to your 87-96 truck, it belongs in our suspension forum.
We have other forums to spread the load of all the threads. We can't have everyone posting whatever question they have in the 87-96 forum just because it's an 87-96 truck, it would be a massive pile of questions/issues and it would have no organization.
This thread doesn't belong in the electrical forum because the 02 sensors are specific to the engine/truck. The wiring/electrical forum doesn't discuss o2 sensors (just general wiring).
A leveling spring thread is a GENERAL suspension question, not specific to your 87-96 truck, it belongs in our suspension forum.
We have other forums to spread the load of all the threads. We can't have everyone posting whatever question they have in the 87-96 forum just because it's an 87-96 truck, it would be a massive pile of questions/issues and it would have no organization.
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Hey omni i have had the same problem with my 1992 F-250. Come to find out that not only was my o2 sensor bad but my EGR Valve and EVP sensor is also bad which can cause the same problem. But my truck has a little larger problem and that is I also have bad rings. My truck threw the codes 41 and 34 I believe when I had some diagnostics done on it. Good Luck!!!
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Sometimes the O2 sensor code will go away when you fix the other problems. If the other problems throw your mixture off enough that the computer can't compensate you get the O2 sensor code. It's kinda like a free added bonus code sometimes.
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I replaced the 02 sensor, cause I think it was due anyway, I think your suppose to change them every 50,000 miles, my truck has 100,000 and it had never been changed, I have an appointment at the local ford dealer on thursday, theres one mechanic over there I really like,he's going to hook it up to his scope, and check some of the stuff out for me, I don't have enough knowledge yet to play with it myself, I've done all I can do with it, plugs,wires,rotor-cap,02 sensor,PCV, air&gas filter, I use to be a back yard mechanic when I had my 1977 f150, now with this 1994, I'm a back yard parts changer. Hey can you get codes without the check engine light coming on? thanks Randy
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From: New Jersey
I sure hope you were generous with anti-size compound (the gray, grainy stuff) before you put it in.
Otherwise in about 10K miles, its a permanently mounted o2 sensor!
If not, and you try to crack it out, more than likely the threads on the "Y" pipe will go with the sensor.
Been there, swore at that
Otherwise in about 10K miles, its a permanently mounted o2 sensor!
If not, and you try to crack it out, more than likely the threads on the "Y" pipe will go with the sensor.
Been there, swore at that
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had the truck checked out at ford all was good they did a motovac on it which is a fancy term for injector flush. it stumbles abit when idling, the mechanic said thats a characteristic of the 5.8 it's the valve overlap timing.bla bla bla, I guess, what do I know. had the cats removed. all I do know is it goes like snot now, and the gas mileage has improved, this truck was in need of a tuneup real bad when I got it. but all is well for now.
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