Byprodriver

If you pull the oil extraction pump you will get a better look but sounds like a chain has come loose some how. Unbolt the oil pump with the 4 outer bolts only & pull straight out mark how it is oriented because it only works right in that position. The cam cover will probably have to be removed to see exactly what went wrong, but the engine is repairable by someone that has done this before. I would inspect the IMS bearing before starting the engine again.

Macster

The Boxster engine is an interference engine and if the cams were not turning the engine would not crank but long enough for pistons/valves to make contact.

If the engine is cranking, if you're able to turn the engine over even by hand (with the plugs removed), the cams are turning and the cam timing is within some reasonable timing envelop.

What you may be seeing behind those green plugs is hardware that (I'm guessing but based on what you report I think I'm right) does *not* turn with the cams, so you are be being misled into thinking the cams are not turning when in fact they are.

There is the slim possibility a cam chain (or two but one's all that is needed) has jumped time. For a cam chain to jump time upon engine cranking at start up suggests a chain tensioner/guide failure and this is almost certainly a catastrophic failure. Not necessarily engine death but very very serious and caution must be used to proceed to avoid turning a salvageable engine into a unuseable core.

To eliminate this as a possible cause for the symptoms you have reported (and some of the symptoms I would have expected you have not encountered) requires more tear down of the engine and I'm not sure you want to go there yet.

However, for you to have been able to continue to crank the engine with no further degradation of the cam timing to me makes the possibility of a camchain having jumped time more remote. My thinking is if a cam chain tensioner/guide system was so bad as to allow the chain to jump time upon initial engine crank at what would have otherwise been a normal engine start, what is keeping the chain from jumping even futher out of time when you crank the engine again? Nothing that I can think of.

I have the Boxster OBDII reference manual and later this evening (after working hours) I'll post the tests for diagnosing possible camshaft position sensor problems.

Sincerely,

Macster.

Byprodriver

Cam is all you can see with the green plug removed & the side with the Oil pump has a large notch cut in it so it will be easy to see if it is turning.

robertsmau

I was looking down into the threads of what I think is the end of the cam and no movement at all. I really wanted to do an upgrade on the engine anyway. Anyone know of a good source for 3.4L motors? I'm on a tight budget so I'm interested in a good used motor.

Macster

If you want the engine to be bad so you can justify a 3.4l engine swap (which is not going to be as straightforward as you might think -- the 3.4l engine has VarioCam Plus and the engine controller/firmware in your 2001 will not know how to control this very critical variable valve timing and variable valve lift system to derive the full benefit of the 3.4l engine) then I will not post the camshaft position sensor diagnostics steps.

(I got really jammed up last night and didn't finish work until after 9pm and needed to get away from the office to avoid putting in a 12 hour day.)

However, if you want the info email me and provide in the email an email address I can use to send PDF files of the steps and I will do so at my earliest convenience.

Added: My mistake! There is a 3.4l engine that fit rather well in the earlier Boxsters and that's the 3.4l engine from the earliest years of the 996! When I posted I only had in mind the 3.4l engine that appeared later in the Boxster S and Cayman S.

Sorry for posting the wrong info.

Sincerely,

Macster.

robertsmau

I forgive you. ha ha

Prelude Guy

Hello,

I am having the same issue with my car. Did you ever figure this issue out?

Thanks!