It wouldn't need to be guides. It could just be seals. Oil has a very low octane and if it's getting pulled down the guide(s) because the seal(s) is/are bad it will definitely cause knock for the same reason RRR sells the AOS. Oil in the combustion process in any significant amount is very bad (think blending octane around 30). It's also possible the EGR function created using cam timing instead of a dedicated exhaust return method could be responsible for knock. I am very curious about a couple of things - has anyone done a leakdown test on an engine with these issues? Anyone notice oil consumption issues (a quart or more in 2k miles or less)? It seems odd to me the cam drive motors would be failing this early, that' why I am curious about other basic health issues.

 

So just got the call from the dealer, they drove it for almost an hour, and no issues. Put it on the lift and couldn't hear much(one thought was headers were making a pinging noise and leading car to assume engine pinging). Not even charging me for the diagnosis. I am going to pick it up tomorrow and try my darnedest to get KCLV back under 15 and bring it to them. Sadly the same thing has happened for nearly two months now. Starts to drive terrible and magically goes back to normal. Will keep stock intake/tune on and see how it goes.

As far as oil burning, I have not seen any. Changed oil earlier this week, and time before that was about 3k mile ago. Since I got it at 50k(now at 55k) I've changed diff fluid, spark plugs(with great compression test results), changed MAF, changed air filter on both the stock and the tuned intake box, reset transmission settings, tried stock airbox/tune, changed the cam motor gear, fresh all seasons, even had every inch paint corrected and ceramic coated and minor things custom wrapped.

Next on the list were tensioner and serpentine belt, because it made a squeaky noise once in the cold morning. But was considering changing the 02 sensors and possibly knock level sensors, though I am told they're right by valley plate. Valley plate has yet to be done so guess it could all be knocked out at once. But tired of throwing money at it with not much result. Every time I think it's fixed and splurge, it comes back lol.

 

same mods, 2011 with 50k miles. Also changed my MAF to no avail. Hasn’t been happening recently, but I also haven’t been driving it long distances.

 

Does this happen after sitting for a longish period or is it truly random? When my Supra sits for a long time I get blue smoke on start up because the exhaust valve stem seals leak a little and over a long time, they leak enough to have some oil smoke on start up. It doesn't last but a few seconds, but if something like this were happening on the intake side it could cause the issues you are seeing and be a telltale sign of the root cause.

 

My car never sits more than a day max. I put at least 30 miles on it every weekday and much more on weekends.

Just picked car up from dealer and drove it around for 2 hours hoping it would show symptoms again but it didn’t. KCLV stayed at 22-23. Guess I’ll keep stock box/tune on for a few weeks and see how it goes.

 

Just out of curiosity could it be bad gas? I just had an issue that caused my KCLV to drop randomly which turned the christmas lights on the cluster. My buddy works at lexus so he looked at it. He came to a conclusion that it might have been bad gas. It was weird because I only use shell or BP gas only. I was at about a 1/4 tank on fuel. So we put some fresh fuel and the KCLV jumped right up. Since it doesn't happen to you all the time.
Only mods i have are JOEZ intake elbow and RR Racing Air/Oil Separator. i have about 150k on my car. First time this has happened to me.

 

I've considered it. But I mainly stick to Shell 93 and use a bunch of different stations. It has happened a few times within 20 miles of filling up, but has happened without filling up also. Plus over the past month I must have filled up at least 5-8 times and it's not been an issue. So I doubt it.

 

Run an e30 mix and see what happens. My car responds very well to e30.

 

are you tuned to be running that?

 

You don't need to be tuned. The car will usually compensate for that much ethanol on its own. I wouldn't go any higher than that.

 

I've been running E40 for the past year and no issues with the standard FBO tune from RR Racing. Although I think that's the upper threshold before diminishing returns without the proper tune to rectify the AFR for the mix in use beyond that.

 

I have the RR tune, which goes very well with e30-e35 (what I run).

 

Update: Not sure I am comfortable running E85 or E30 especially with no tune that may adjust for it. Majority of the threads I have seen regarding that are those who are limited to 91, and thus want to bump up closer or just past 93 levels. I have good 93 near me and have used octane booster in the past.

Either way, I don't think that is the case of my issues. Since my last post a week and a half ago I have put about 300-400 miles on the car with the stock box and tune. KCLV has steadily remained at 21-24 and car runs great. With the tune off, I do have the CEL, so I've decided to get PPE extenders as well as new 02 sensors just in case that was an issue also. Was recommended new O2 sensors by a buddy with an SC RCF as he's had several issues with them also making his car run worse.
Speaking with Eric at PPE, he mentioned that he has seen some people have issues with intakes too. I've always felt that may have been my issue as it all started when I added to the RR intake a new RR CF elbow as well as a fresh air filter. Maybe there's a pinhole leak somewhere in the bypass hose, or the intake itself since it's several years old. Nothing visual I could see though. Not sure if it's the case either since I ran fine for 3 weeks with the box/tune/elbow and it ran fine then too. Who knows.

Will keep the stock tune/intake on till spring just to make sure, then start playing with the intake box and tune again.

 

Did you happen to check if you have any codes pending? My symptoms were particularly bad today (did play around with the intake piping right before, may be related?) and found these codes. No cel indicator though. Wonder if this is a symptom or a cause of the issue.

 

The only two codes I have are 420/430 for the catless headers. With stock tune and air box I’m at 1k+ miles currently without issue. KCLV has been at 22-24 nearly whole time and car runs strong. Haven’t changed O2 sensors yet as I’ve been without issue. Edited to also include that every drive I do I run the same OBD fusion app and monitor KCLV among other things.