CEL Coming on and Turning Off

[BLACKESTSHEEP]

thanks..i'm new here on the forum, and i'm not sure where exactly the o2 sensor is on my 89 ford festiva carbed..i will search the forums, but if you happen to know where i can look, or help me out, i'd appreciate it..thanks again...i'm an amateur at repairing, and if its possible to do myself, i will...i wont do anything major, but the o2 sensor looks like a small device, and may not be too hard to do for a guy like me....

[Spike]

Looking at the engine from the front of the car, look down behind the radiator and directly on the front of the engine. Look for the exhaust manifold (where the pipe comes down from the engine, going to your muffler), there will be a sensor coming out of the manifold, with a wire coming from it. That is your o2 sensor.

[BLACKESTSHEEP]

thanks spike!..you gave a good description, so i shouldn't have trouble finding the o2 sensor..i'll take a look for it later today, and report back...now, is there any 'trick' to installing it.._?...does it just screw in and out..?.....i have looked in the forums and on the net, and it looks pretty easy...i dont have the special "o2 sensor tool" that helps you screw it in and out without damaging the wires, but i should be able to get it out with care if i take my time, or i will get a proper tool if necessary...also, one forum member recommended looking at the 'rockauto website' to order a new o2 sensor, ..do you have suggestions..?

[TominMO]

Sheep, at least get a Haynes manual. It will save you time asking lots of basic questions, especially when there is a pic in the book. Most people get the Denso sensor. You can get it out with a box wrench by unplugging it first, then passing the wire from the sensor thru the box wrench. I forget exactly what size, maybe about 7/8" or so. Might have to tap it with a hammer to set up some vibration to break it loose. Use anti-seize when installing the new one--it's usually in the box or already on the threads. I use a lot just to make sure.

[BLACKESTSHEEP]

ok, thanks for info..i have a 'ford shop manual', ...but your right, that's not much help at all when it comes to the 02 sensor..i'll look into getting the 'haynes manual' then instead... , i think i can get in there now, it doesn't look like too hard a job, ..i am a novice, and i just i wasn't sure whether it was considered a 'major' repair, and i didnt want to screw anything up..lol again, thanks for your help

[TominMO]

ok, thanks for info..i have a 'ford shop manual', ...but your right, that's not much help at all when it comes to the 02 sensor..i'll look into getting the 'haynes manual' then instead... , i think i can get in there now, it doesn't look like too hard a job, ..i am a novice, and i just i wasn't sure whether it was considered a 'major' repair, and i didnt want to screw anything up..lol again, thanks for your help

Many repairs are very easy, once you've done it the first time. An O2 sensor change isn't much different than changing a spark plug. Same with struts, valve cover gasket, camshaft seal, etc etc. Some jobs have a lot of steps, but they are usually all easy steps. You just need experience. If you still feel a little shaky about just jumping into a project with both feet, maybe grab someone knowledgeable to look at the issue and give you a minute or two of advice. Or ask on here. But getting a Haynes manual will help you to ask more advanced questions, and not waste time waiting for answers to basic questions.

As to changing the O2 sensor, there is more chance of the threads in the exhaust manifold being hosed due to rust, than with a spark plug. It is nice to have the proper O2 sensor socket, but sometimes it's actually easier to use a box wrench. Depends on how rusted-in the sensor is. If you encounter a lot of resistance, hit it with PB Blaster and wait an hour, try again, squirt some more on if needed. Also hit the wrench with a hammer or something to set up vibration; that often helps. It can also help to warm up the motor a little, say 30-60 seconds, to loosen things up.

[BLACKESTSHEEP]

hi TominMO..thanks again for all your advice, and taking the time to describe everything in detail, its much appreciated....i do agree with you that the repairs become easier once you do them once or twice..i was a bit hesitant at first, but i have replaced the spark plugs, spark plug wires, radiator flush, back flush replaced the fusible links, replaced air filter, and completed oil and filter changes over the years..and not really a 'repair'..but i also removed the rear seat to lighten the car up....

I know these are all very simple repairs lol, but i'm trying to eventually 'graduate' to the larger projects as i learn more...the o2 sensor will be my first more involved repair...with some help from the forum here, and your advice, I'll eventually get in there, and tackle the project...i'll also take your advice, and i'm going to order a haynes manual first, and look it over first, and that will give me a better idea of how everything fits together in the bigger picture...i'll let you know later how my progress is going, and whether i'm successful with the o2 sensor...or, lol, if i get stuck....

[nitrofarm]

Sheep, do exactly what Tom said and you'll be fine. One thing to add if I may...Once you get the O2 sensor to "Snap Loose". Dont just spin it out,now is the time to get any kind of thin oil on the threads. This is true for any spark plug or fastener. Spray oil onto the threads as best you can and work it in by turning the sensor 180 deg. And then more oil,then go backwards in the opposite direction.Keep working the fastner back and forth to break up any chips of rust and metal. Once youve broken enough bolts loose you'll know right away how much caution (and oil) you'll need to apply. Sometimes you snap a plug loose and they come right out. But on one that I dont know who put it in and if they used never seaze I error on the side of caution. Haste makes waste Good Luck you can do it!

[BLACKESTSHEEP]

hi nitrofarm..and thanks for your advice and words of encouragement on my 02 sensor repair..you have given me a wise piece of advice concerning lucubrating all the plugs and fasteners i will be removing from my car..indeed, they can get stuck in there, and be very difficult, and frustrating, to extract.!..i need to remember to lube everything up, and it will make my job easier the next time i have to get in there and tug and twist on things.....i also agree with you, that it's best to take your time on things, and not rush it, and be patient..that has helped me alot in my repair endeavors so i dont feel overwhelmed or get frustrated...I'm going to first read up on some forum posts on the o2 repair here in the forums, then i'll write you guys back and let you know my progress and how it went..thanks again for all your sage advice :mrgreen: