Curious if anyone has dealt with an issue like this previously. Did some searching and couldn't find anything exactly like this.
2007 Cayman
@ 70k. Couple days ago, the "check engine / visit workshop" lamp came on. Gas tank was almost empty, thought it might be related to poor gas quality or a cap not fitted correctly. Turned out not to be the case. Stopped by a nearby Euro mechanic (not my primary
Porsche
only mechanic, but they seem like a really solid shop) to check the code. Turned out to be "System Too Lean Bank 1" which repeated a few times. The mechanic thought it might be a crankcase issue. Basically, the digital diagnostic tool had a checklist of possible issues he was going to check. I asked if it was safe to drive about 5 miles, he said yes, don't go far, and I took it home.
A couple things to note - there are no anomalies I could tell while driving. No vibration, loss of power, or horrifying noises. That said, right as I got a block away from home, I noticed when I slowed to a stop, there was a bit of a squealing noise that would only happen on deceleration. Not a brake noise. More like a belt noise. Wasn't sync'd to the brakes, per se, but definitely seemed to only happen during decel. Anyhow, parked it in the garage and now wondering if anyone has experienced this before, and if I should drive it back to the mechanic. Crankcase? Imminent AOS issue? Something else?
Sounds like a tow is worth the money to be safe (I don't have free tows right now, I know...) but just curious if anyone has thoughts on what this could be, or experienced anything like this. One other thing to add, every now and then I get the puff of white smoke on startup, which I hear is common with these models. But I'm not seeing billowing white smoke or anything like that.
Could the noise be a vacuum leak ?? That could cause a lean condition.
Someone else mentioned it could be a failing AOS. Sounds like a compelling theory (and perhaps not mutually exclusive with what you mentioned too).
Yea sounds like you should take it in. "Tow", you probably did not mean it but Do Not Tow your car! Either drive it or get it tailored. Assuming there are no Oil pressure issues you are probably safe driving the car into the dealer. Good Luck!
This could be bad fuel as you mentioned but also failing oxygen sensor (most often) or dirty or failing injector. If you do not have oil warnings I believe you can drive the car to the shop. CEL ligths are usually related to emission controls which is fuel cap, O2 sensors, dirty injector or throttle body, dirty or failing MAF sensor or something like that. Good luck!
Indeed!
Thanks for the replies! Will report with the results.
So, turned out to be the AOS. In addition to the faults (System Too Lean, Bank 1 & 2) the tell-tale sign of the separator's diaphragm failing was a suction when removing the oil cap while running, and eventually a whistling squeal (like a bird chirp) when decelerating/idling. $400 all said to fix, only took a couple hours, not to shabby.
Great news, time to drive and enjoy again.
