DB's997

All of a sudden she is running like crap! I took my MY 2000 996 C2 in for a state safety inspection last
Thursday and noted how smooth it was idling during the inspection. Later that day I stared to hear a knocking sound at idle.
The knock became worse. Now I am scared to drive the car as it sounds so bad.

I am having it towed to Momentum Porsche on Tuesday morning. The car has 44,000 miles on her and is due for the 15,000
mile checkup. Thought I would have Porsche do the 15,000 mile service and fix the bad idle.
Hero to zero in less than a day?

Hurdigurdiman

dyu have any idea where the knocking is coming from? Theres not a mechanic still under the hood from the inspection is there? Phone the garage and ask are they missing a mechanic... You could turn that sub woofer up so you dont hear the knocking lol

ivangene

might be a cracked coil that got wet.. start there

KrazyK

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DB's997

I take offense to that...
No CEL, don't have a code reader. BTW, there is no code to read!
I never expected my 12 year old Porsche to be like new. That is why I take such good care of it......................................................
Just no respect around here.
The dealer will give me their opinion tomorrow. So long.

KrazyK

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DB's997

OK, My hero is a zero today. Will find out how much over 0.0 it is tomorrow at the dealer. RATS!! I hate going to the dealer with their $100,000 plus cars in the showroom.

txhokie4life

Was it a knocking -- or a tapping --- to me knocking is lower frequency in Hz (internal engine/crank)
and tapping is a higher frequency (valve), A whacking sound could be a chain that has broken,
or a tensioner/chain guide that has given out.

You already have the IMSR -- so that's a good start. Does the occurrence rate track the RPM?

Don't be surprised if they come abck and just tell you you need a new engine -- its very costly
for them to go beyond basic diagnosis

If you end up having to have some engine issues addressed
my buddy in Austin rebuilds M96 engines and is pretty reasonable ($75/hr).
So anything including a compete rebuild is right up his alley.

Mike

DB's997

I would be very suprised if the dealer says I need a new engine!
it was running great last week. 30K service done a year ago,
IMS replaced just a few months ago. That is what is so strange,
it was running so good. Then within an hour it started this idle
knocking and I just had to shut her down.
Will find out soon.

Gonzo911

Good luck. Lets hope the emissions inspector simply left the gas cap off.

ccaarmerciill

Good luck, hope it's nothing too serious. Be sure to report back when it's solved.

Thundertub

Sometimes it is something relatively minor like the gas cap mentioned above, or maybe some vacuum hose that fell off, or some water in the gas, to the MAF sensor needs a squirt of cleaner. The last is exactly what happened to me a couple years ago. Just needed some MAF cleaner and it ran fine again. No CEL warning, just started running rough.

Sounds like you are driving your car enough to keep things lubed up. That is a VERY good thing.

fasteddie99

These engines have 24 modes of failure.
IMS is just 1.

DB's997

Had it towed to Momentum Porsche. They called back and said to get some decent sleep tonight, just the water pump! :
So for around $1400 I am back in the saddle again! That is a Christmas gift I can appreciate!

jrgordonsenior

I doubt anyone would have guessed that but it does make noise when they let go. Don't know about $1,400. though....