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Discussion Starter · #1 ·
Alright here we go...

I had my downpipe and catback installed at a shop locally. I was going to do it myself on jackstands with basic tools but after I had them install it, I’m SO happy I had them do it.

Not only did the catback come cut too short (making them have to add a section of pipe to the car ((thanks Roush!), but the factory bank 1 sensor 1 (PRE cat — CLOSEST to the turbo) was destroyed in the process of removing it. After only 4500 miles! Thanks Ford!

So here’s where it gets interesting... The shop plugged bank 1 sensor 1 location on the new downpipe and plugged “a” sensor into the bank 1 sensor 2 location. The reason I say “a” is because if sensor 1 was destroyed in the process of removing it (which it was, I have all the parts), then why is my car showing code P0135 Bank 1 Sensor 2. ON MY CAR there is a sensor plugged into the downstream location. The one closest to the rear of the car. Why am I showing a code for sensor 2? Isn’t that sensor 2 location? Am I confused or something? Did they plug sensor 1 into the sensor 2 location? I thought they destroyed sensor 1 during removal though?

I’m so confused!!!!!!!!!! Which sensor is the important one to have? Are they both equally important? Is sensor 2 actually the one closest to the turbo? I’m sooooooo confused!
 

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Bank 1 sensor 1 is the important sensor as it controls fuel mixture. The ST is a closed loop fueling car and without it your AFR will be all over the place. Bank 1 sensor 2 is there just to monitor the catalytic converter efficiency. They have different connectors so they cant be swapped. They can however be swapped on the DP which is no bueno
 

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And this is why I do all the work I can myself...


Also why is it Ford's fault that your shop destroyed the OEM sensor? Seems like plenty of people on here have been able to remove their OEM down pipes without theirs getting jacked up. Seems more like the fault of your shop instead of Ford.

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And this is why I do all the work I can myself...


Also why is it Ford's fault that your shop destroyed the OEM sensor? Seems like plenty of people on here have been able to remove their OEM down pipes without theirs getting jacked up. Seems more like the fault of your shop instead of Ford.


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Exactly!
The dp removal wasn’t easy, but wasn’t really all that difficult either. I managed to wiggle my old fat arse underneath and did it using only jack stands & Rhino ramps. I’d never tried anything like that before either. The shop you took it to dropped the ball, not Ford. There’s already enough things to blame Ford for with these cars, so let’s not pile on here.:crazy:
 

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Discussion Starter · #5 ·
Bank 1 sensor 1 is the important sensor as it controls fuel mixture. The ST is a closed loop fueling car and without it your AFR will be all over the place. Bank 1 sensor 2 is there just to monitor the catalytic converter efficiency. They have different connectors so they cant be swapped. They can however be swapped on the DP which is no bueno
And this is why I do all the work I can myself...


Also why is it Ford's fault that your shop destroyed the OEM sensor? Seems like plenty of people on here have been able to remove their OEM down pipes without theirs getting jacked up. Seems more like the fault of your shop instead of Ford.

Sent from my Pixel XL using Tapatalk
Just as I thought, sensor 1 is the important one. Now if the sensor before the cat is the one they destroyed, then HOW am I showing a code for sensor 2 and not sensor 1? The car runs great. Just fine. Exhaust smell is normal (for not having a cat) and car runs and performs such as you’d expect. The only explanation I can think of is that the ECU labels the pre cat sensor, #2 and the post cat sensor, #1. That’s the only way this makes any sense. My car shows a code for sensor 2 and the sensor I’m missing is the one closest to the turbo. The one they destroyed is the one closest to the turbo.

And he called me prior to destroying it and told me they tried all the tricks in the book and couldn’t break it loose without a mean squealing sound. He asked permission to just torch it and try to get it out intact and I said go for it. The threads were completely f****ed up.
 

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That is strange it was too short, I had Roush and installed it myself with no issues. I would contact them about the length not being correct.

I have heard of some O2 sensors being cross threaded. I would be interested if the sensors are flipped around on the Dp (which would be kinda hard to do since they are different lengths) Or maybe a sensor is not plugged in all the way.
 

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Just as I thought, sensor 1 is the important one. Now if the sensor before the cat is the one they destroyed, then HOW am I showing a code for sensor 2 and not sensor 1? The car runs great. Just fine. Exhaust smell is normal (for not having a cat) and car runs and performs such as you’d expect. The only explanation I can think of is that the ECU labels the pre cat sensor, #2 and the post cat sensor, #1. That’s the only way this makes any sense. My car shows a code for sensor 2 and the sensor I’m missing is the one closest to the turbo. The one they destroyed is the one closest to the turbo.

And he called me prior to destroying it and told me they tried all the tricks in the book and couldn’t break it loose without a mean squealing sound. He asked permission to just torch it and try to get it out intact and I said go for it. The threads were completely f****ed up.
If they put the sensor 2 in sensor 1 position on the DP then its overheating the sensor and thus the code. I would log and check AFR. I doubt highly its running right.
 

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Discussion Starter · #8 · (Edited)
Just as I thought, sensor 1 is the important one. Now if the sensor before the cat is the one they destroyed, then HOW am I showing a code for sensor 2 and not sensor 1? The car runs great. Just fine. Exhaust smell is normal (for not having a cat) and car runs and performs such as you’d expect. The only explanation I can think of is that the ECU labels the pre cat sensor, #2 and the post cat sensor, #1. That’s the only way this makes any sense. My car shows a code for sensor 2 and the sensor I’m missing is the one closest to the turbo. The one they destroyed is the one closest to the turbo.

And he called me prior to destroying it and told me they tried all the tricks in the book and couldn’t break it loose without a mean squealing sound. He asked permission to just torch it and try to get it out intact and I said go for it. The threads were completely f****ed up.
If they put the sensor 2 in sensor 1 position on the DP then its overheating the sensor and thus the code. I would log and check AFR. I doubt highly its running right.
Then where’s my code for sensor 1? And how would it be overheating if it’s in the downstream location (Furthest from the turbo)?

They put A SENSOR in sensor 2 location. I just don’t get it. And obviously none of you have any clue as to what’s going on either or we’d have an answer by now. They destroyed sensor 1 and the evidence is clear because I have the old pipe and the old sensor.

On my new pipe, sensor 1 is plugged and sensor 2 has A SENSOR in it. But my car is throwing a code for sensor 2. Nothing is mentioned of sensor 1 and the car feels fine.

Like HOW!? Hahahaha!
 

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If you're running without your upstream sensor stop driving that damn car.

You might be getting a failure because the somehow put the downstream sensor in that spot, which would be problematic as well.

Make sure you get those straightened out asap and make sure they're in the correct order.
You definitely don't want to be messing with the wideband sensor being out of correction.

Typically swapping your exhaust is a low risk situation but that is a good way to destroy that engine.

Best of luck!
 

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Is there a bank 1 sensor 1 installed in the DP in the right location? Or was it broke and they installed the second sensor in the location of sensor 1? Sensor 2 can be put in the 1 position on the DP but 1 can not go into 2 because like said above the the wires are too short. They have different connectors also so they cant be swapped when plugged in. Get under there and check to make sure and see whats installed where.

Sensor 2 on the top

IMG_20180207_114725.jpg

Connectors

IMG_20180207_114746.jpg
 

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Discussion Starter · #11 ·
Is there a bank 1 sensor 1 installed in the DP in the right location? Or was it broke and they installed the second sensor in the location of sensor 1? Sensor 2 can be put in the 1 position on the DP but 1 can not go into 2 because like said above the the wires are too short. They have different connectors also so they cant be swapped when plugged in. Get under there and check to make sure and see whats installed where.

Sensor 2 on the top

[iurl="http://www.focusst.org/forum/attachment.php?attachmentid=309914&stc=1&d=1518033081"]
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Connectors

[iurl="http://www.focusst.org/forum/attachment.php?attachmentid=309922&stc=1&d=1518033119"]
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Sensor 2 is most definitely plugged into sensor 2 location. I was under the car last night. Sensor 1, the shorter one in the picture, had destroyed threads and is now long in the garbage. There is no sensor plugged into sensor 1 position.

So now from our discussion on this thread I can most certainly tell you that sensor 1 is missing from the car and sensor 2 is in the correct location on the downpipe.

That helps clear things up, except for the fact that the AP shows a code for sensor 2, and nothing for sensor 1, and the car runs normal.
 

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Sensor 2 is most definitely plugged into sensor 2 location. I was under the car last night. Sensor 1, the shorter one in the picture, had destroyed threads and is now long in the garbage. There is no sensor plugged into sensor 1 position.

So now from our discussion on this thread I can most certainly tell you that sensor 1 is missing from the car and sensor 2 is in the correct location on the downpipe.

That helps clear things up, except for the fact that the AP shows a code for sensor 2, and nothing for sensor 1, and the car runs normal.
Ok got it. For sure the car is not running normal fuel trims and the code is because you went catless. Need to disable sensor 2 or put a defouler in
 

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Discussion Starter · #13 ·
Sensor 2 is most definitely plugged into sensor 2 location. I was under the car last night. Sensor 1, the shorter one in the picture, had destroyed threads and is now long in the garbage. There is no sensor plugged into sensor 1 position.

So now from our discussion on this thread I can most certainly tell you that sensor 1 is missing from the car and sensor 2 is in the correct location on the downpipe.

That helps clear things up, except for the fact that the AP shows a code for sensor 2, and nothing for sensor 1, and the car runs normal.
Ok got it. For sure the car is not running normal fuel trims and the code is because you went catless. Need to disable sensor 2 or put a defouler in
The AP has the capability to permanently disable the CEL for sensor 2 correct?

I tuned to stage 3 and the CEL was off the entire night, then now today I start the car and it’s back. Bank 1 Sensor 2 code P0135. Thought going stage 3 disabled that.

I find it interesting that there’s no code for sensor 1 and it’s absolutely not in the car. Lol! Your pictures were a great help in figuring this out!

Now I’m curious, since I’m so new to tuning, is there something I can monitor to check if the car is indeed running lean or what-have-you?
 

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The AP has the capability to permanently disable the CEL for sensor 2 correct?

I tuned to stage 3 and the CEL was off the entire night, then now today I start the car and it’s back. Bank 1 Sensor 2 code P0135. Thought going stage 3 disabled that.

I find it interesting that there’s no code for sensor 1 and it’s absolutely not in the car. Lol! Your pictures were a great help in figuring this out!

Now I’m curious, since I’m so new to tuning, is there something I can monitor to check if the car is indeed running lean or what-have-you?
Monitor AFR, long term fuel trim (LTFT) and short term fuel trim (STFT) See if there is a Lambse also
 

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OP needs way more education and research before doing mods, or paying someone else to do them incorrectly.
Sorry for your situation, what a mess.

 

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then now today I start the car and it’s back. Bank 1 Sensor 2 code P0135...

I find it interesting that there’s no code for sensor 1 and it’s absolutely not in the car. Lol!
interesting enough, when I google that code, everything that pops up says bank one, sensor one... which IS the sensor you are having problems with...

Screenshot_20180207-211215.png

Screenshot_20180207-211341.png



now if that shop was smarter, they should have told you that either they need you to bring them a new sensor or send some one out to get one so that they could put it back together. have fun getting that plug out and the new sensor on the car while the DP is installed and I personally wouldn't drive the car hard (or at all) until its replaced, especially with a tune on it.
 

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Discussion Starter · #19 ·
then now today I start the car and it’s back. Bank 1 Sensor 2 code P0135...

I find it interesting that there’s no code for sensor 1 and it’s absolutely not in the car. Lol!
interesting enough, when I google that code, everything that pops up says bank one, sensor one... which IS the sensor you are having problems with...

[iurl="http://www.focusst.org/forum/attachment.php?attachmentid=309986&stc=1&d=1518056212"]
[/iurl]

[iurl="http://www.focusst.org/forum/attachment.php?attachmentid=309994&stc=1&d=1518056226"]
[/iurl]



now if that shop was smarter, they should have told you that either they need you to bring them a new sensor or send some one out to get one so that they could put it back together. have fun getting that plug out and the new sensor on the car while the DP is installed and I personally wouldn't drive the car hard (or at all) until its replaced, especially with a tune on it.
How very odd... I never googled the code. I just trusted my accessport. The very first day I got the car back from the shop this is the code that appeared on my tuner. It’s always been the same one. Bank 1 sensor 2. P0135. Wtf.

After discussing the problem on this forum I ordered bank 1 sensor 1 and the shop said they would put it in for free for me. So that’s good anyway.
 

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