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Is IMS failure possible while starting engine?


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The car normally starts fine. I went to start my 2001 911 996 Carrera (triptronic) for the first time of the day. It cranked normally and right at the point of starting something changed, almost like the amount of mass being cranked got lighter.

I'm trying to find out if there is a way to confirm or rule out the IMS failure The engine will still turn over and the serpentine belt is going around normally. I just don't know how the failure presents itself other than from others have said about the engine makine all kinds of noises and sometimes leaking oil.

The only other possible time where I've noticed when an engine cranks differently is when it has no fuel. On some engines it will sometimes feel like the engine is cranking less mass.

Please, please, please, oh please don't let this be the dreaded IMS failure. Any help on troubleshooting would be greatly appreciated.

Thanks

Rob

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In general, the IMS tends to fail while the engine is running, but there is nothing that would prevent it from "buying the farm" while trying to start.. That said, you issue could be any number of things: bad fuel pump, bad fuel pump relay, crank position failure (always a favorite), bad ingnition switch, etc. When the crank position sensor goes out, the DME thinks the engine is not turning, so it shuts off the fuel and spark; no start.

Some diagnostics are in order; you need to determine if you have fuel pressure. If you have access to a Durametric system, it should be able to not only see any codes, but it could also run cam deviation values to see if they are where they are supposed to be (dead give away is if the cam timing has jumped).

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In general, the IMS tends to fail while the engine is running, but there is nothing that would prevent it from "buying the farm" while trying to start.. That said, you issue could be any number of things: bad fuel pump, bad fuel pump relay, crank position failure (always a favorite), bad ingnition switch, etc. When the crank position sensor goes out, the DME thinks the engine is not turning, so it shuts off the fuel and spark; no start.

Some diagnostics are in order; you need to determine if you have fuel pressure. If you have access to a Durametric system, it should be able to not only see any codes, but it could also run cam deviation values to see if they are where they are supposed to be (dead give away is if the cam timing has jumped).

Thanks JFP. I do not have access to a Durametric system and the car is stuck in my garage. I guess if you're going to break down that's a great place to do it. But I can do some research and troubleshoot these items (e.g. check for spark the ole fasion way) and see if anything pops up.

But it sounds like there may not be a solid way to rule out/rule in the IMS. But I'll put this on the bottom of my check list.

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