997 puff of smoke on start up

[robertmark]

My 997 over the last two days upon start up puts out a puff of smoke. It has never done this before. The only thing I have done recently was had the clutch replaced. At that time I also replaced the RMS. They inspected the IMS and found it to be the dual row ceramic, in excellent condition. I typically keep the oil right at the full mark. It is currently on the last bar, could this do it? The car is currently at 35,000 miles. Thanks!!

[JFP in PA]

Originally Posted by robertmark

My 997 over the last two days upon start up puts out a puff of smoke. It has never done this before. The only thing I have done recently was had the clutch replaced. At that time I also replaced the RMS. They inspected the IMS and found it to be the dual row ceramic, in excellent condition. I typically keep the oil right at the full mark. It is currently on the last bar, could this do it? The car is currently at 35,000 miles. Thanks!!

You are over filled, drop it a bar or two. Also check the crankcase vacuum as your AOS may be going out.

[robertmark]

Originally Posted by JFP in PA

You are over filled, drop it a bar or two. Also check the crankcase vacuum as your AOS may be going out.

I was actually only at one bar on the oil reading, so I was on the low side. What is the AOS? Thanks

[tonythetarga]

AOS = Air oil separator.
How are you checking your oil? It has to be on level ground and been at 'rest' for at least 30 minutes. One click of the key and let it meter the oil. If you check before it has all had a chance to drain down, you will show low. Then you'll add oil and, you're overfilled.
You should show an "arrow to arrow' reading as normal oil level. If the top bar if also lighted up, you're overfilled. The question is "how much over?" You won't know unless you drain some back down, let the car sit and measure again.

[robertmark]

Thanks guys. When I checked the oil it was after sitting over night. The oil was at the lowest bar. The last two days it blew out a plum of smoke on start up. I'm going to have wife start the car tonight while I watch from behind all tail pipes. If smokes tonight, I'll check into the AOS.

[tonythetarga]

Follow up question to your original post. You don't mention what year 997 car you have but based on the IMS statement, it must be an early 2005, otherwise the IMS bearing isn't replaceable from the outside. (engine would have to be disassembled to do that). Just curious to know if it is an '05 with an M96 casting or an M97 casting. It is one way to evaluate the honesty of the mechanic that serviced the car and whether they opened the trap door to look at the bearing.

[robertmark]

It is a late 2006. When doing clutch they told me I had the better ceramic IMS bearing. They are very reputable and advised I didn’t need to spend the money to replace the IMS.

[tonythetarga]

The ‘06 to ‘08 cars had the large, non-serviceable IMS bearing. It is not ceramic. It is a sealed bearing and the balls are not visible unless the seal has been removed.
If it has a ceramic bearing, the engine was rebuilt as it can only be replaced from the inside.
This may be a reputable shop but the info does not sound correct.

[robertmark]

They showed me a sample of the bearing that fails, and they showed me a sample of what mine looks like. Mine was considerably larger. They may have mentioned some replacements are ceramic, and not that I have one. Was dealing with my sick mother at the time, so more than likely it was my wires crossed. Didn’t smoke on start up today.