I am at watkins glen and developed a boost problem today. It came on rather slowly. Normally I get 1.4 bar with the aquamist system EPL installed, but boost started fading to 1.2 then 1.0, and now maxing out at 0.6 bar. With the reduced boost and power came that too familiar waaaaaaaaaa sound. I thought for sure that I had developed a boost leak ( popped or split a hose) so I boost tested it from the topside to 25 psi and it held pressure. Hmmmm.

I the put my durametric on it and read the codes. It had two codes as follows:

P0045 boost pressure control valve first stage open circuit
P0133 Porsche fault code 15 - oxygen sensor ageing period bank 1

Is it likely that I have a faulty oxygen sensor and is it likely that this is what is causing the problem? If so, can I get a new one at a regular auto parts store?

If not likely the problem, any ideas of what to test next?

Thanks for any help. I am trying to save the next three track days

 

Could this be an issue with the N75 valve or vacuum leak of some sort?

 

Check all the lines and connector to the N75. If one came loose your car is trying to tame the boost. Hope it's an easy fix out there.

 

It took a little while to diagnose, but I found the source of my boost problem. It was a loose cat disc in my exhaust (driver's side). I suspected this might be the problem as it happened once before, but it's a PITA to pull the bumper, intercoolers and exhaust if it's not the problem. I even had someone rev the engine to see if I could feel any difference in exhaust pressure and I could not. Fortunately, I had my scope with me and was able to pull an O2 sensor and see that in fact the cat disc was sitting sideways in the exhaust. So apart it came, and I got a local shop to cut the exhaust open and remove the cats and weld it back together. Everything is good now.

With that behind me, I feel compelled to warn others about this issue as it happened twice to me, and apparently once to at least one other owner of the same exhaust. They were both Europipes, with mine being a stage two quiet. The first time it happened, Europipe covered it under warranty and told me that the only way it could have happened was if the car backfired thereby blowing out the disc. At the time I thought BS, but since they were fixing it "one time for free under warranty" I didn't challenge them.

Now to be fair, my car is running 560hp to the wheels and I track the sh*t out of it -- it happened on my eigth connsecutive day at Watkins Glen. I bought the pipe for the performance and because I liked the sound and low level of drone, but cannot recommend it for anyone who really drives their car hard.

All that said, I was posting 2:10s on consecutive laps at the Glen, which I was pretty happy with.

Thanks to all who chimed in with advice. This was a tricky one and I hope one that no one else needs to experience, as it is not easy to diagnose.

 

Amen to that. Good to meet you Joe and I'm glad you were able to sort it out and get it back on the track in one day. Bravo!
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Good to meet you too Larry. Your car looked great. Love the splitter.

We need to get more sixspeeders out to Watkins Glen. It is a high horsepower friendly track, so our cars eat it up.

 

I bailed on my trip to the Glen this year, partially due to weather concerns and the other due to 14 hr tow. Weather turned out beautifully. Won't let that happen again.

 

Hey Heavy,

Too bad you didn't make it. I would have grilled you on spring rates. I think mine are too soft. I have Moton CSs with 550F, 850R, which is how they came (bought them lightly used). The fronts in particular, feel a little soft.

I just started running Hoosier R6s on this trip to the Glen and loved them -- I took 2.5 seconds off my lap times and I ran 2:10s when they were fresh.

Via search, I read that you were running 900/1150, which feels maybe too stiff compared to what others say they are running. At those rates does the car feel twitchy at all in corners? Does it still signal the coming loss of grip? I was thinking 800/1000. What do you think given that I will run R6s with -3.2 and -2.5 camber respectively?

Also, I listened to Tire Rack and ran 245/40 (39psi) and 295/30 (41 psi) R6s, but think I could upgrate the backs to 315/30s? I also heard Kumho V710s are almost as good and last 50% longer and could run them in 305/30 and 245/40 sizes. Any thoughts here?

Sorry for all the questions, but I love tracking the car and am looking for every second I can find.

 

TO SOFT! i have 600 front 800 rear jrz setup with eibach springs and they rattle my teeth!

 

Wow I wouldn't have thought that happened with the EP. Then again +- 700hp for 8-days would pound on any cat! Glad to see you got her all set no casualties.

Sam

 

Glad you were able to figure it out, one to definitely write down for the future for those of us with cats.

 

Joe,

Sorry to hear that your cats have failed for the second time. We use Emitec cats and they are the OEM supplier for Porsche. The stock 996 TT exhaust has 300 cell Emitec cats while ours are the 100 cell variant. They should last for years unless there are backfires inside the exhaust. The backfires are due to ignition interruptions or to an overly rich fuel mixture. Ignition interruptions are caused by worn coils packs or worn spark plugs. In this case the rich fuel mixture is caused by the tune.

We've sold hundreds of these exhausts to customers in the U.S. without warranty issues but we've sold 2 exhausts to your tuner and the cats failed 3 times. The first time I've renewed the cats under warranty and paid the shipping costs as well. It makes no sense to renew them again as there is a big chance that they will fail again with the same tune.

There is no need to raise the threshold for the secondary O2's when using our exhausts but if it's raised and the cats fail then you'll have no clue what's going on.

Hope this info makes sense to all. Any questions, please ask.

Thanks

 

I tried them, V 710's are really sticky first few days, they fall off very quickly, run with low pressures. I run 1200R/800F with Motons 2 way - cab so heavier car - runs great.