Completely Stumped and Getting Kinda PO'd!

[SonnyJack]

I'm at VIR for day 1 of what should have been a great two day event, but I've been dealing with an unknown gremlin. I have absolutely no power and no clue why. No new codes have been thrown. I say new because my O2 sensors have been shot for a while and they are the only codes. I never go into limp mode, I'm not leaking anything, and nothing mechanical appears broken, but the car literally falls flat on it's face at about 5,000 RPMs. Basically I'm running about 1/2 throttle and my left arm is getting a serious workout!

Car ran great for the first two laps this morning and ever since it's been a disaster. Last track day was a month ago and the car pulled strong all day.

At idle all sounds fine, but as soon as I get on the gas the engine sound changes (gets deeper), car begins running rougher, and is just dead. I'm assuming if I was down a cylinder I'd be throwing codes. No? If anyone has any ideas I'm all ears.

If I didn't know any better I'd swear I got some bad gas, but everyone has been using the same pumps as me.

[Redd]

Plugs?

[SAMM3Y]

Kinked vacuum line somewhere? Just had a kinked line on one of my street bikes and gave similar symptoms. No codes but erratic throttle control and boggy power..

[fsmtnbiker]

Plugged cats from your dead oxygen sensors...

[SonnyJack]

Originally Posted by fsmtnbiker

Plugged cats from your dead oxygen sensors...

Sadly I'm thinking this is it. Sat in my trailer re-reading SYT's thread and while I haven't had any smoking, the symptoms appear all too similar. The catless x-pipe was due to go on in a few weeks since the car is no longer street driven.

Really hate causing my own problems....

[SonnyJack]

Originally Posted by Redd

Plugs?

Plugs are good

[SonnyJack]

Originally Posted by SAMM3Y

Kinked vacuum line somewhere? Just had a kinked line on one of my street bikes and gave similar symptoms. No codes but erratic throttle control and boggy power..

Thanks for this possibility. I'll check this morning. Thinking perhaps it could be a cat issue. Hope not.

[VictorH]

Really sorry to hear that. Nothing worse than sitting at VIR in blazing heat and humidity and your car is not running right.
There's a race shop at VIR (just outside the gate in the big complex on the left heading out the main gate). They are nice, very helpful and maybe they could take your x-pipe off and see what things look like. Won't get you back on the track as you still need your O2 sensors in place but at least you could rule-in or rule-out that problem.

[SYT_Shadow]

Originally Posted by SonnyJack

Sadly I'm thinking this is it. Sat in my trailer re-reading SYT's thread and while I haven't had any smoking, the symptoms appear all too similar. The catless x-pipe was due to go on in a few weeks since the car is no longer street driven.

Really hate causing my own problems....

I read your opening post and thought this sounded familiar. I certainly hope this isn't your problem.

Are you on OEM cats? I melted my aftermarket ones

The Xpipe can be dismounted in the paddock, it's worth shining a flashlight into the cats. Before they fail all the way they start looking different.

Given my ordeal I suggest you stop running the car at the event and take it to the shop VictorH suggests

[SonnyJack]

Originally Posted by SYT_Shadow

I read your opening post and thought this sounded familiar. I certainly hope this isn't your problem.

Are you on OEM cats? I melted my aftermarket ones

The Xpipe can be dismounted in the paddock, it's worth shining a flashlight into the cats. Before they fail all the way they start looking different.

Given my ordeal I suggest you stop running the car at the event and take it to the shop VictorH suggests

Laughing reading this. Not haha laughing, rather "I'm a dumbass" laughing. I ran four laps this morning, underpowered, and as if on cue, noticed I was smoking. Needless to say I'm on the trailer and about to head home. This event was way underrepresented and should have been a great time. Unfortunately, my procrastination in putting on the catless x-pipe has bit me in the ass. At least that's what it seems like.

I have the ESS x-pipe. You had this one as well if I'm not mistaken. I don't have near the number of track days you've had but I've been SC'd and generating massive heat for almost three years.

Appreciate you taking the time to post.

[SonnyJack]

Originally Posted by VictorH

Really sorry to hear that. Nothing worse than sitting at VIR in blazing heat and humidity and your car is not running right.
There's a race shop at VIR (just outside the gate in the big complex on the left heading out the main gate). They are nice, very helpful and maybe they could take your x-pipe off and see what things look like. Won't get you back on the track as you still need your O2 sensors in place but at least you could rule-in or rule-out that problem.

Thanks Victor. Really appreciate your suggestion on this. That shop saved me last year when I ran out of methanol. They called around and got ahold of the manufacturing of my kit, and confirmed that washer fluid would work in the place of 49/51 methanol. I basically emptied out the closest Dollar General and had a blast. They are definitely great guys.

Thanks again!

[tdott]

Is it the primary O2s?

As you probably figured out, you don't want to run for too long with bad primary o2 sensors. Also being supercharged makes it even worse. Hope you sort it out.

[SYT_Shadow]

Originally Posted by SonnyJack

Laughing reading this. Not haha laughing, rather "I'm a dumbass" laughing. I ran four laps this morning, underpowered, and as if on cue, noticed I was smoking. Needless to say I'm on the trailer and about to head home. This event was way underrepresented and should have been a great time. Unfortunately, my procrastination in putting on the catless x-pipe has bit me in the ass. At least that's what it seems like.

I have the ESS x-pipe. You had this one as well if I'm not mistaken. I don't have near the number of track days you've had but I've been SC'd and generating massive heat for almost three years.

Appreciate you taking the time to post.

I'm sorry to hear that. Even with fewer track days your car outputs way more heat than mine, so it may be that.
It's easy to inspect: remove the xpipe and shine a flashlight into the cats.

Yes, I also had an ESS HFC Xpipe. It's nice that it keeps the primary cat position but for heavy track use (or supercharged track use which is the same thing) it seems to have an issue.

Some people will climb onto a high horse and talk about how brand X cats don't melt and blahblahblah. However if you look at xpipes that run the HJC or whatever cats which are supposed to be the best they have a 1 or 2 year warranty. My ESS HFC Xpipe took 3 years of double-tracking before failing, so I don't blame it.

Now I run the Bimmerworld resonated Xpipe and got Magnaflow metallic cats welded in after the X. This keeps them cooler than in the primary position and also allows the exhaust from both banks to exit through a single pipe if needed.

If you are smoking then you've blown the valve stem seals of the bank affected by the -assumed- melted cat. Step 1 would be to check the cat.
If one or both cats are melted then here is what I'd do after all my ordeals:
-Get a shop which can work on these cars. Something reputable. Deansbimmer, jcolley, IMGMotorsport, etc.
-Have them pull the engine and replace the valve stem seals
-It's up to you whether you get the mains inspected/replaced or not. I did not and my engine failed soon after I put it back in. Needless to say I would NOT do that again
-You may also want to get the rod bearings replaced

I ran my engine thousands of miles with the failed cat after mechanic after mechanic inspected it and replaced parts left right and center but did not diagnose the issue. It felt horrible but every one of them agreed that 'it would get better' and other BS.
Before the engine blew I had spent 10k chasing the issue. At least you have the opportunity to learn from my mistakes, this was an incredibly painful experience.
It's possible if today was the first time the engine seemed 'off' you can get away with just replacing the valve stem seals. That is up to you.
The 3 mechanics that misdiagnosed the car were all BMW specialists. That is why I recommended the 3 shops earlier. There are lots of 'specialists' but few people know the S65 well. I will not make the same mistake again

By the way a welder can turn the ESS HFC Xpipe into a catless resonated Xpipe very easily, just replacing the failed cats with pipe. This may allow you to sell your unused catless one to recoup some of the costs of this ordeal.


Our car died at the Glen. It was so down on power but with R1's we ran a personal best in the car chasing down a 991 GT3 RS. It was a worthy sendoff for the S65, but it's still a shame it happened. It could have easily been prevented.


Best of luck and don't hesitate to PM to discuss in more detail.

[SonnyJack]

Dropping the car off at RRT over the weekend. Will post what they find.

[SonnyJack]

Originally Posted by SonnyJack

I'm at VIR for day 1 of what should have been a great two day event, but I've been dealing with an unknown gremlin. I have absolutely no power and no clue why. No new codes have been thrown. I say new because my O2 sensors have been shot for a while and they are the only codes. I never go into limp mode, I'm not leaking anything, and nothing mechanical appears broken, but the car literally falls flat on it's face at about 5,000 RPMs. Basically I'm running about 1/2 throttle and my left arm is getting a serious workout!

Car ran great for the first two laps this morning and ever since it's been a disaster. Last track day was a month ago and the car pulled strong all day.

At idle all sounds fine, but as soon as I get on the gas the engine sound changes (gets deeper), car begins running rougher, and is just dead. I'm assuming if I was down a cylinder I'd be throwing codes. No? If anyone has any ideas I'm all ears.

If I didn't know any better I'd swear I got some bad gas, but everyone has been using the same pumps as me.

Well, the verdict is in!

Slightly frustrated with the outcome, given I alerted the shop in advance to what I thought the problem was (and they proceeded to check multiple other things to no avail before being reminded a second time of the concern with the cats). Looks like my issue is similar to what SYT_Shadow experienced with the same ESS center section. Hopeful that mine was caught prior to the same catastrophic ending. Definitely perplexed because there was an obvious impact on the damaged side and I have no idea what could have caused that.

RRT put on an undamaged center section and all of the anomalies disappeared. No misfire, no rough idle, no loss of power. The damaged cat had been driven back into the exhaust as far back as the second O2 sensor. Also had them corner balance and align the car so should be good to go. Car weighed 3,605 lbs ex-driver and with half tank (3,785 with my Lilliputian self).

Heading to PittRace on the 9/21-22 so will find out then. Installing catless system tomorrow. Major thanks to SYT and everyone else who provided input. Much appreciated!

SJ

[///Mobbin]

Congrats on figuring this out! And darn, those appear to be the same HFC's that I have on my car. Any idea if those are Magnaflow 59956 200 cell cats?

[SYT_Shadow]

Glad to see you got it figured out. Hopefully your engine is 100% happy the next time you take it out.

///Mobbin, I use magnaflow cats on a BW Xpipe that originally was catless. I think the difference is that the ESS one has the cats in the primary position and it gets way too hot with superchargers or serious track use. I'm confident the same cat in the secondary position, where I have them on the BW Xpipe, will last without issues

[SonnyJack]

How on earth do people go catless with a daily driven car? The sound was intoxicating, but the smell......

[roastbeef]

can we see a better pic of the damaged catalyst? seems like an easy thing to inspect from time to time and its not too clear in the pic.

[SYT_Shadow]

Originally Posted by SonnyJack

How on earth do people go catless with a daily driven car? The sound was intoxicating, but the smell......

it's horrible, that's why I will put cats in the secondary position, the smell is just too awful

[tdott]

Originally Posted by SonnyJack

How on earth do people go catless with a daily driven car? The sound was intoxicating, but the smell......

I'm catless for 2 months now, I haven't noticed much of a smell. Not as bad as my catless E46 m3 was.

It's not driving with Windows down weather here in FL right now, so the only time I smell it a bit is when I leave the car running and get out.

With my rear section and headers, it's also the quietest catless setup I've ever heard. My original plan was to weld in some hfc when I couldn't stand it anymore. But so far it's not bothering me.

[SonnyJack]

Originally Posted by roastbeef

can we see a better pic of the damaged catalyst? seems like an easy thing to inspect from time to time and its not too clear in the pic.

I'll see what I can do.