MexicoBlueTurboS

I am going to throw a little bit of AFAIK into this discussion. # 1 it's rarely one thing, and more often the tide - wave after wave that cause catastrophic failures.

AFAIK - there is a general consensus that engines need to be warmed up under load and that any aggressive accelerations shouldn't occur until the engine components have reached what might be called a thermodynamic homeostasis or equilibrium. This might take up to 20 minutes depending on the ambient temperatures.

Additionally, with DFIs, there is a tendency of excess fuel to wash the cylinder walls of lubricant with unburnt fuel accumulating during long idle periods. This would be a situation where one wouldn't want to do a hard acceleration after sitting in the McDonalds drive thru or some of the exceptionally long lights that can be encountered during rush hours. I know of several that take up to 10 minutes to get through because the programming is poor for the actual traffic loads E-W and N-S.

Jake and other engine experts could probably list 100 other mechanical failures or weaknesses that can be factors in kabooming an engine. Sometimes it just might be bad luck.

When we were at the P factory my buddy was paying real close attention to the engine assembly line where there were several duplicate stations putting engine components together. He noted that one worker used almost all of the three minutes to lube the part thoroughly before installing it while the worker in the adjacent station just dabbed the grease on and slapped the component into place in about 1/6th of the time. My friend observed this 4 times in a row. All else being equal, I know which engine I'd want in my car.

RacerWannabe

Good points all. Just says "1 month or 1,000 mile, bumper-to-bumper warranty". No exclusions listed. I told the seller already that I dropped off the car on Wednesday to be inspected for the cause of the knocking sound.

INTMD8

Yes, I think you will be good if you stand your ground. Fingers crossed it's good but if not and the warranty company they use kicks it, they should take care of it.

Balr14

Bump for an update.

RacerWannabe

Wish I had one for you guys! Planning to call in the AM to get an idea of where things stand...

speedracerf4i

My 09 C4S with 23K miles has that ticking noise as well. I think it's normal. I will check tonight to see if that thumping noise is normal or not.

RacerWannabe

I think, and any RL’ers feel free to chime in here, that we’ve agreed that yes, the ticks are normal. The knocking/slapping sound isn’t..

dgjks6

Agreed. I spent some time under my 2009 this weekend with the car running and listening to these videos. I got all the ticking but none of the knocking that o heard in the first video.

sandwedge

Might be part of the explanation for the large variances in oil consumption in these cars. My -09 C4S went through a quart every 1,000 miles while my -11 GTS hardly burns any oil at all. There's a RL member here who took European delivery of a brand new 2006 C2S that has gone through a quart every 600-700 miles since brand new and still does with I think more than 70,000 miles on it now. By comparison, my -06 C4S used next to no oil. So these variances are similar between .1 and .2 cars.

I believe Porsche allows as much as a quart every 600 miles as ok but also sets that as the limit for acceptable/normal oil consumption.

knightma

There are about 6 taps per second which indicates a tap every 2 revs at idle (720 rpm). I’d say this rules out bore scoring which would be every rev so double this frequency. It appears to be something running at cam shaft speed.

Mike Murphy

Doesn’t the piston slap against the bore on the ignition cycle (every 720 degrees)? Rod knock has a similar sound - it’s the same as the cam timing (720) because the ignition is what causes the rod to knock, but doesn’t always happen on the other revolution because there’s not as much pressure.

MexicoBlueTurboS

It's a definite slap in the face. And it makes me sick because my very first Porsche was sold to me with a bum engine and I'm certain the seller knew it.

I drove it back from LA to KC and while it was losing power all the way (it really struggled in the Rockies) - it made it all the way to Topeka KS before finally giving up.

Yep - same sound.

groovzilla

Seems like it's taking an awfully long time to get some answers back on engine knocking?
Hope results lead to good news.

groovzilla

Wow never heard that story--->Can't trust anyone selling a car unless they are RL member or similar. **Did you have PPI performed??
PPI would have found the engine noise in the current op's engine I believe. Hard to miss it.
I'm really hoping OP gets good news.

RacerWannabe

PPI performed. Was told engine performed and sounded normally. It does seem to perform normally, with a very slight misfire just off idle only. Can’t believe this was thought to sound ‘normal’