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2014 Fiesta ST upstream oxygen sensor

JPGC

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Middleburg
#1
Good morning,
About a week and a half ago, I installed my race downpipe from 2J racing. It was definitely a pain in the a$$. Not because of the actual install, but due to the fact that the factory upstream o2 sensor being soooo tight. I wrenched on it, soaked it with PB blaster and wrenched some more. It finally came loose, but in the process, the sensor is bent and has a couple of dents in it. Well, I got everything back together and start the car. It started up fine, idled okay, though a little rough. I plugged my Accessport in and found that the air fuel is locked at stoich (14.7). I drove it a few miles and the engine light popped up saying that bank 1 o2 sensor is not warming up.
So, last week, I ordered the o2 sensor (9f472A (DY-1285)) from Ford. This o2 sensor was and is still on back order until at least Aug 4th- Aug 19th. My question is, in your opinion, would it be safe to drive the car lightly and out of boost until I get this part in? I appreciate any help and for future reference to you all, don't mess this sensor up when changing out the downpipe, lol. Thanks
 


rooSTer

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Miami
#2
Its going to idle like crap get poor fuel economy but I've seen guys drive with bad o2 sensors all the time.
 


OP
JPGC

JPGC

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Thread Starter #4
I don't mind the temporary poor economy and idle. I can deal with that. I just want to make sure that it's not going to destroy the engine, lol. I actually drove it a few miles and the car felt good driving and I did not hear any knock, detonation, etc.
 


OP
JPGC

JPGC

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Thread Starter #5
I checked Rock auto and the one that matches the proper sensor is a non stock. The part number for the one that they list for the upstream is for the downstream sensor. I have already paid Ford and I also called dealerships all over the US and the all say the same thing....back ordered. They were saying that there are 25 already paid for on order, including mine.
 


CanadianST

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Location
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#7
Those sensors are definitely in tight. Took me standing on the downpipe and my buddy hitting a wrench with a hammer to finally break it loose. Glad to see you found a replacement though
 


OP
JPGC

JPGC

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Thread Starter #8
Yeah, lol, I cussed at this car for an hour straight over that. How did you get the downpipe out with the upstream o2 sensor in place?
 


CanadianST

Active member
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#9
Yeah, lol, I cussed at this car for an hour straight over that. How did you get the downpipe out with the upstream o2 sensor in place?
I had to cut off the studs where it mounted to the rmm bracket and twist it every which way from the bottom while a buddy worked at it from the top. Definitely took some time but we eventually got it out.
 


OP
JPGC

JPGC

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Thread Starter #10
In hind sight, I should have done the same as you, but at the time, I didn't want to perminately damage the stock downpipe...once I was done, I really didn't give a crap, lol
 


OP
JPGC

JPGC

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Thread Starter #11
Ugh, still waiting for this O2 sensor....this sucks :-(
 


Messages
22
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1
Location
Miami
#12
Good morning,
About a week and a half ago, I installed my race downpipe from 2J racing. It was definitely a pain in the a$$. Not because of the actual install, but due to the fact that the factory upstream o2 sensor being soooo tight. I wrenched on it, soaked it with PB blaster and wrenched some more. It finally came loose, but in the process, the sensor is bent and has a couple of dents in it. Well, I got everything back together and start the car. It started up fine, idled okay, though a little rough. I plugged my Accessport in and found that the air fuel is locked at stoich (14.7). I drove it a few miles and the engine light popped up saying that bank 1 o2 sensor is not warming up.
So, last week, I ordered the o2 sensor (9f472A (DY-1285)) from Ford. This o2 sensor was and is still on back order until at least Aug 4th- Aug 19th. My question is, in your opinion, would it be safe to drive the car lightly and out of boost until I get this part in? I appreciate any help and for future reference to you all, don't mess this sensor up when changing out the downpipe, lol. Thanks
Hey whats up couole years late but when you finally got tye o2 sensor back did afr unlock ? Mines stuck and dont know what to do my only theory is the same issue you had the o2 sensor being a bit bent
 


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