Our X5 just failed the Emissions Test - Opinions needed!

[msammy]

Thanks for all of the replies and good advice friends, that's why I come here for help. I don't post many questions, only when I'm stumped. I've searched the internet for days and found more info on this one thread, so thank you!

Originally Posted by upallnight

That's the parts cannon method of fixing the X. Keep throwing parts at it until the code don't come back.

What app are you using with the bluetooth scanner? If it's Torque or OBD fusion, they have a freeze frame in the app that takes a snapshot of the engine data (PIDS) when the computer throws up an SES or CEL light. When the engine throws up the another SES or CEL, look at the freeze frame before clearing the trouble code.

Before replacing the 02 sensors look to see if they are active when the engine is running and in close loop. Torque and OBD Fusion allows you to view the activity of the 02 sensors. If they are active then it's not a sensor problem.

Look at the long terms and short terms trim data when the engine is in close loop. If they are close to 0 then the engine is fine. Do a little bit of research before firing the parts cannon.

The app I'm using is the Carly app which will allow me to monitor voltage on the 02 sensors as well as other things which I haven't done just yet (haven't had time). So today I was able to replace the Air filter (had 8K miles on it but really clean) and cleaned the MAF with MAF cleaner, it looked pristine. I drove her tonight, 58 miles and the SES came back.

So based on everyone's opinion, here's what I've decided on next steps:

o Pull the DISA valve, inspect and replace if it looks bad.

o Replace all 4 02 sensors based on 158K miles on the clock. Let's start fresh.

o If all else above does not fix the code, then replace the CAT on Bank 2 based on the diagnostic code.

One more question, which side is the Bank 2 CAT on, passenger or driver's side?

Thanks again everyone for the feedback and I promise not to let this thread die without final resolution. Be patient, this will take me a while to get fixed as the rear 02 sensors and CAT replacement will need to be done at my Indy since my bad back won't allow me to do on my own!

[upallnight]

Originally Posted by msammy

Thanks for all of the replies and good advice friends, that's why I come here for help. I don't post many questions, only when I'm stumped. I've searched the internet for days and found more info on this one thread, so thank you!



The app I'm using is the Carly app which will allow me to monitor voltage on the 02 sensors as well as other things which I haven't done just yet (haven't had time). So today I was able to replace the Air filter (had 8K miles on it but really clean) and cleaned the MAF with MAF cleaner, it looked pristine. I drove her tonight, 58 miles and the SES came back.

So based on everyone's opinion, here's what I've decided on next steps:

o Pull the DISA valve, inspect and replace if it looks bad.

o Replace all 4 02 sensors based on 158K miles on the clock. Let's start fresh.

o If all else above does not fix the code, then replace the CAT on Bank 2 based on the diagnostic code.

One more question, which side is the Bank 2 CAT on, passenger or driver's side?

Thanks again everyone for the feedback and I promise not to let this thread die without final resolution. Be patient, this will take me a while to get fixed as the rear 02 sensors and CAT replacement will need to be done at my Indy since my bad back won't allow me to do on my own!

Bank 2 on a 3.0 engine is the last three cylinders at the rear of the engine. Both cat are on the passenger side for our cars (LHD).

[msammy]

Originally Posted by upallnight

Bank 2 on a 3.0 engine is the last three cylinders at the rear of the engine. Both cat are on the passenger side for our cars (LHD).

Thanks for the info, I should have looked under the hood before I asked that stupid left/right question! I've done a bunch of work under the hood, I'm just not familiar with the exhaust system as it's 100% original since we bought the truck new.

[CapeX5]

I think I stand corrected. Deansbimmer has much more factual experience than I. Follow his direction.

[upallnight]

Before buying a new cat I would look at the 02 sensors pre cat and post cat for bank 2. Here's a video of the 02 sensors on my X. If the cat is bad the post cat 02 sensor will not be a straight horizontal line. It will bounce up and down like the pre cat 02 sensor.

https://www.youtube.com/watch?v=zyh_4SktmFM

[msammy]

Originally Posted by upallnight

Before buying a new cat I would look at the 02 sensors pre cat and post cat for bank 2. Here's a video of the 02 sensors on my X. If the cat is bad the post cat 02 sensor will not be a straight horizontal line. It will bounce up and down like the pre cat 02 sensor.

https://www.youtube.com/watch?v=zyh_4SktmFM

Great video! This is the first time ever that I wished I didn't have an iPhone as that app isn't available for it. I had a chance to monitor some parameters with the Carly for BMW app. Unfortunately, I have no clue in what parms to look for as the diagnostic section of the app appears more geared towards a BMW tech or at least someone who knows what they're doing and what to look for. The Coding functions are awesome however!

So I took a drive and monitored what I think were 02 sensor parameters and here's a few screenshots of what I collected. The screenshots are taken at various parts of the drive and the faults were cleared and no SES light was on. I'm a bit baffled at what I'm looking at so if you or anyone can let me know what are the Catalyst parameters to monitor and what to look for it would be greatly appreciated!

[upallnight]

Your short term fuel trim is way off the chart, but that could be because of the program. Negative fuel trim percentage means the computer is subtracting fuel by shortening the time interval the injectors are opened. You don't have a Long term fuel trim to compare it with because the computer looks at the long term fuel trim and adjust the fuel percentage in the short term fuel trim. The computer is trying to zero out the fuel trim in both the long term and short term fuel trim by adjusting the fuel mixture.

You can get a cheap android tablet for under $100 or buy a use Samsung or any cheap android phone and just use it to run the Torque App. You don't need to activate the phone.

Have been able to not drink from the Apple Cider jug until last week when I broke down and bought an IMAC for my teenage daughter.

[Deansbimmer]

I'm not sure I would trust those readings in that app.

On a separate note regarding my own repair... I put the new cat in and all of the monitors have reached ready state now.

[msammy]

Originally Posted by Deansbimmer

I'm not sure I would trust those readings in that app.

On a separate note regarding my own repair... I put the new cat in and all of the monitors have reached ready state now.

Very cool, glad to hear your problem is fixed. I'm learning the hard way that exhaust/emissions problems are alot more complicated than most issues we face with our X5's.

[bcredliner]

Originally Posted by Deansbimmer

I'm not sure I would trust those readings in that app.

On a separate note regarding my own repair... I put the new cat in and all of the monitors have reached ready state now.

I don't know if the apps are spot on but my experience is that when there is a problem if there is a +- inaccuracy error it has not been enough to hide the problem.

The closest app to Torque that I know of that is available for an iPhone is Dashcommand.

Where in Texas is your shop?