Rough Idle - Bad 02 Sensor?

[Izzmeister]

Hello Everyone, having a rough idle issue on my 2015 F82 with 50k miles. It's got cat-less DPs, drop in K&N Filters, M Perf exhaust(With Cats) and a Stage 2 Bootmod3 Tune(93 Octane) with GTS DCT tune as well. Just spent a weekend in the Miami sun changing the valve cover for the PCV valve, Oil Filter Housing gasket as well as a leaky Top Mount intercooler....fun!
Anyhow, the car now has a rough idle....runs well but it smells a little like gas - very faintly and the idle is just a little rough dipping below normal. Took it to a reputable shop, they ran all sorts of tests....looks like one of the O2 sensors is on it's way out. Shop couldn't tell me which one. I trust the shop, they are legit. Being that they are over $220 a pop, I don't want to guess which one is on it's way out. Could someone help me out? I ran a Bootmod3 datalog of the idle. My buddy who knows more about datalogs than I do told me it looks like my Bank 2 O2 sensor(s) is bad. Now which one is that? He says the Lambda value in the log shows a bit lean and could cause the car to dump fuel in that bank. Could someone please take a look and tell me which O2 it is? I just want the car to run right. Trying to rekindle my relationship with her lol. What is Bank 1 and 2 on this inline 6? I also have ISTA-D but don't know much on how to use it. Sometimes setting the e-cable is difficult. If anyone has the e-cable settings and a link to an ISTA video how to that would be great. I have attached the Bootmod3 datalog, for someone who knows how to read these things it should be easy. Thank you!

https://www.bootmod3.net/log?id=626c...0b4339634d2719

[TopJimmy]

Check BM3 Diagnostics for trouble codes. Should see something like this

[Izzmeister]

Originally Posted by TopJimmy

Check BM3 Diagnostics for trouble codes. Should see something like this

Originally Posted by TopJimmy

Check BM3 Diagnostics for trouble codes. Should see something like this

It doesn't have any codes

[TopJimmy]

Originally Posted by Izzmeister

It doesn't have any codes

I'm on my phone so hard to see logs. Bank 2 is the rear 3 cylinders, and the short DP. My lower sensor (bank 2, sensor 2) just went. The 12B404 code confirms trouble, then a 12B304 showed a line break for my problem.

[TopJimmy]

It's your Bank 2, and probably the upper more expensive Sensor1 since your AFR is off. The lower sensor doesn't mess up AFR.

[Izzmeister]

Originally Posted by TopJimmy

It's your Bank 2, and probably the upper more expensive Sensor1 since your AFR is off. The lower sensor doesn't mess up AFR.

Originally Posted by TopJimmy

Check BM3 Diagnostics for trouble codes. Should see something like this

So bank 2 is 3 cylinders closest to firewall? Sensor 1 is the upper sensor on that bank, correct? Just before downpipe I believe. If you have the part number that would be great!
Thanks man

[TopJimmy]

Yes, Bank 2 is closest to firewall, Bank 1 towards the grill.

I think you're looking at Part #2 in the diagram.
Put the last 7 of your VIN into RealOEM website.

[Izzmeister]

Originally Posted by TopJimmy

Yes, Bank 2 is closest to firewall, Bank 1 towards the grill.

I think you're looking at Part #2 in the diagram.
Put the last 7 of your VIN into RealOEM website.

Awesome, ordering it now. Thanks for the help, much appreciated.

[Izzmeister]

I ordered and installed the OEM O2 Sensor, Bank 2 Sensor 1. Car idles better but still a little rough and smells like gas. Pulled a few datalogs at idle. On cold start, the O2 sensor I changed still reads a little lean. Once the car warmed up, started and logged again - it missed hard for a second then adjusted. I don't know what's up with it now. Any help would be appreciated, guy helping me says to just wait for the check engine light. I want it running right, smell of gas at idle and the fact it doesn't feel like it's burning clean bothers me. The plugs are new and the coil packs are less than 2k miles on them. I'm running out of ideas.....Thanks

Initial Cold Start:
https://www.bootmod3.net/log?id=627c...90c61547e3a79c


Start-up after warm(Hard misfire early, drops in RPM)
https://www.bootmod3.net/log?id=627c...729b15b567d1a6

One more time:
https://www.bootmod3.net/log?id=627c...0b436c7c3f347e

[TopJimmy]

Rear bank still has the AFR off. Pull the rear three plugs and examine for one stinky or wet with gas. I think you may have a leaking injector. The exhaust tips wet with fuel is a sure sign. Don't run the car so you're not pushing fuel past the rings into your oil.

[Izzmeister]

Originally Posted by TopJimmy

Rear bank still has the AFR off. Pull the rear three plugs and examine for one stinky or wet with gas. I think you may have a leaking injector. The exhaust tips wet with fuel is a sure sign. Don't run the car so you're not pushing fuel past the rings into your oil.

Originally Posted by TopJimmy

Rear bank still has the AFR off. Pull the rear three plugs and examine for one stinky or wet with gas. I think you may have a leaking injector. The exhaust tips wet with fuel is a sure sign. Don't run the car so you're not pushing fuel past the rings into your oil.

How can I be sure of what the issue is? There are no codes, just a rough idle on start-up and it smells rich. Tailpipes only show some condensation. Burns with a little white smoke, the water coming from tailpipes is just morning condensate - wiped it off and it doesn't smell like gas. I don't want to do injectors like I did O2 and still have the same issue. There has to be some troubleshooting steps to figure out what the exact issue is. Injectors are about $90 a piece and require a special tool for extraction/installation plus the seals. Don't want to go down that route and have the same issues again. Is there something I can do in Ista to see that my injectors are out of whack? Some sort of test that will tell me there's a fault not detectable by the DME yet?
Thanks

[TopJimmy]

I don't use ISTA or know if there's a check. Sorry, computer cars…

I look at my plugs to know what's going on.

[Izzmeister]

Originally Posted by TopJimmy

I don't use ISTA or know if there's a check.

I look at my plugs to know what's going on.

Originally Posted by TopJimmy

I don't use ISTA or know if there's a check.

I look at my plugs to know what's going on.

I might pull the plugs and see. Plugs are new NGKs gapped at .022 as per BM3 for my tune. Coil packs were done about 6 months ago or 2k miles. Once I did coil packs which threw no codes the car woke up. Ran really good, this idle thing is pissing me off. Too much tech on these cars. Going back to Chevy next time around, lol….Z06 is much simpler.

[Izzmeister]

So I pulled a data log, STFT and LTFT as well as lambda values and AFR all shows good. I logged the misfire count, cylinder 1 at idle seems to miss a little. Logged about 3 misfires in cylinder 1 in a span of 80 seconds at idle. I pulled the plugs just now, the plugs are all fine. No gas smell and I swapped the plug in cylinder which was misfiring for a new one. Also changed coil pack 1 for cylinder 2 coil pack and moved cylinder 1 coil pack to cylinder 2. I re-seated all the coil packs and made sure the plugs were torqued to spec and checked all grounds to injectors, coil pack wiring and injector wiring making sure everything was connected properly. Fired it up, ran 3 data logs. A cold start after I did the work, then a warm idle with some driveways revs and an idle log with a few revs in driveway after a short aggressive drive. Now it shows misfires in multiple cylinders at random. This points to one thing, coil packs. I don't think it's plugs, they all looked good with no smell of gas and gap is perfect at .022 for the NGKs. Coil packs are OEM replaced less than 2k miles ago. It's the only thing that makes sense, car runs better but is still rough at idle and smells pig rich. Maybe I need new coil packs? I hear OEM is the best....should I go OEM or who makes them for OEM? Is it Delphi? A link to which ones would be great. If my issue is coil packs.

1st log, cold start after swapping cylinder 1 for fresh plug and swapping coil pack 1 to cylinder 2 and vice -versa:
https://www.bootmod3.net/log?id=6285...90c61ded8fcad3

2nd log, car is now warm - idle and a few driveway revs:
https://www.bootmod3.net/log?id=6285...90c61fd35b6a24

3rd log, after a quick drive and some accelerating for log in driveway:
https://www.bootmod3.net/log?id=6285...0b43790f93115e

Your help is much appreciated, thanks!

[Info@mad-us.com]

Originally Posted by Izzmeister

So I pulled a data log, STFT and LTFT as well as lambda values and AFR all shows good. I logged the misfire count, cylinder 1 at idle seems to miss a little. Logged about 3 misfires in cylinder 1 in a span of 80 seconds at idle. I pulled the plugs just now, the plugs are all fine. No gas smell and I swapped the plug in cylinder which was misfiring for a new one. Also changed coil pack 1 for cylinder 2 coil pack and moved cylinder 1 coil pack to cylinder 2. I re-seated all the coil packs and made sure the plugs were torqued to spec and checked all grounds to injectors, coil pack wiring and injector wiring making sure everything was connected properly. Fired it up, ran 3 data logs. A cold start after I did the work, then a warm idle with some driveways revs and an idle log with a few revs in driveway after a short aggressive drive. Now it shows misfires in multiple cylinders at random. This points to one thing, coil packs. I don't think it's plugs, they all looked good with no smell of gas and gap is perfect at .022 for the NGKs. Coil packs are OEM replaced less than 2k miles ago. It's the only thing that makes sense, car runs better but is still rough at idle and smells pig rich. Maybe I need new coil packs? I hear OEM is the best....should I go OEM or who makes them for OEM? Is it Delphi? A link to which ones would be great. If my issue is coil packs.

1st log, cold start after swapping cylinder 1 for fresh plug and swapping coil pack 1 to cylinder 2 and vice -versa:
https://www.bootmod3.net/log?id=6285...90c61ded8fcad3

2nd log, car is now warm - idle and a few driveway revs:
https://www.bootmod3.net/log?id=6285...90c61fd35b6a24

3rd log, after a quick drive and some accelerating for log in driveway:
https://www.bootmod3.net/log?id=6285...0b43790f93115e

Your help is much appreciated, thanks!

I wouldn't think a coil pack would cause that at idle. Did you replace the plugs or just check them?

If the misfires are all on the same bank you may have a bad o2 not a dead one.

[Izzmeister]

Originally Posted by Info@mad-us.com

I wouldn't think a coil pack would cause that at idle. Did you replace the plugs or just check them?

If the misfires are all on the same bank you may have a bad o2 not a dead one.

Originally Posted by Info@mad-us.com

I wouldn't think a coil pack would cause that at idle. Did you replace the plugs or just check them?

If the misfires are all on the same bank you may have a bad o2 not a dead one.

What started all this was a rough idle and a gas smell at idle. Data logged it, TopJimmy helped me diagnose a bad O2 on Bank 2 sensor 1. Replaced it, running better but still rich at idle. Logged again, Jimmy says take a look at plugs - might have a leaky injector. That's where my last post starts…I removed plugs, looked them all over and only replace cylinder 1 because that's where the misfire count was. Because I also re-seated all coil packs and now I'm seeing misfires in more cylinders via Bootmod3 data log - I'm guessing it's coil packs.

[Info@mad-us.com]

Originally Posted by Izzmeister

What started all this was a rough idle and a gas smell at idle. Data logged it, TopJimmy helped me diagnose a bad O2 on Bank 2 sensor 1. Replaced it, running better but still rich at idle. Logged again, Jimmy says take a look at plugs - might have a leaky injector. That's where my last post starts…I removed plugs, looked them all over and only replace cylinder 1 because that's where the misfire count was. Because I also re-seated all coil packs and now I'm seeing misfires in more cylinders via Bootmod3 data log - I'm guessing it's coil packs.

Multiple coil packs going back would be rare. In my experience they just go bad when pushed hard and the cyl turns off.

None of the plugs were wet or black correct? Assuming they are 97506 how many miles on them?

[Izzmeister]

Originally Posted by Info@mad-us.com

Multiple coil packs going back would be rare. In my experience they just go bad when pushed hard and the cyl turns off.

None of the plugs were wet or black correct? Assuming they are 97506 how many miles on them?

Originally Posted by Info@mad-us.com

Multiple coil packs going back would be rare. In my experience they just go bad when pushed hard and the cyl turns off.

None of the plugs were wet or black correct? Assuming they are 97506 how many miles on them?

Plugs are new 97506, less than 200 miles. They were clean, no build up or wear of any sort. Nice, clean plugs as expected after 200 miles.

[clutchdj]

go back to stock software and test from there?

[Info@mad-us.com]

Originally Posted by Izzmeister

Plugs are new 97506, less than 200 miles. They were clean, no build up or wear of any sort. Nice, clean plugs as expected after 200 miles.

And when did this start?

[Izzmeister]

Originally Posted by Info@mad-us.com

And when did this start?

Originally Posted by Info@mad-us.com

And when did this start?

I had a bad pcv valve, leaky intercooler and oil filter housing gasket about 2 months ago. Did all the work myself, pretty straight forward. It started giving me the rough idle issues right after that. I checked all my work today, everything seems good. There really isn't a way to screw it up. It's just connectors and clips. If I had a loose ground or something I would get a CEL. What gets me is the Fuel trims and O2 readings are all good. Misfires and running rich at idle on multiple cylinders after new plugs and relatively new coil packs? I don't understand where the issue could be with no codes.

[TopJimmy]

Maybe one of your small black air tubes aren't connected good. Check that all your fittings are clipped in good, especially to the long intake tube and the J-pipe nipples.