Hey guys. Long time since Ive had to post. I drove my car today, had a few random misfires. Figured its time for new plugs (been a few years). Car sat about an hour. I fired it up to move it in my buddies driveway and now there is a crazy ticking/tapping from the passenger side. This isnt the usual Mezger tick. Ive owned this car for 7 years and never heard anything like it. The oil was a bit low so I topped it off. Went and grabbed my durametric, no codes. When I rev the motor, the tapping gets louder and speeds up. I drove the car home a few miles and it runs/drives normal. Its just super loud. Am I right to assume I had a failed lifter?

I was a tech for 10 years. Never had a variocam motor apart. Is this a DIY, or do I need a Porsche specialist? Either way, Ill drop the motor myself.

Thanks all.

 

video of sound

 

Dry sump - if you were a little low, it wouldn't matter. The car would be fine with 4 litres if you weren't racing. So, I can't point you to the problem because I haven't had that one, but I can say low oil wasn't a factor.

 

So I did an oil change for sh*ts and giggles. The noise is far less quiet, but its there. After letting the car warm up to full temp, I tried taking it for a ride in my neighborhood. I am now seeing a constant misfire in bank 2. Cylinders 4-5-6 misfiring non stop. I am going to check the Bank 2 cam solenoid and bracket next.

All these issues started last week when I got misfires from a vacuum leak. I found a bad diverter valve which caused a massive leak and threw SAI codes and bank 2 misfires. I installed new DVs yesterday. It was misfiring a bit when I first drove it, but after a few short pulls, the misfire went away. Scanned it with my Durametric to be sure and there were no codes. After that I drove about 10 miles to a buddies house. As soon as I pulled in, the misfires started up. I left the car sit about an hour, fired it up and it was still misfiring. I revved it up a bit to see if the stumbles would go away (they had prior when I revved it) thats when this ridiculous tapping/knocking started.

Are there any values I should be comparing to rule out cam solenoids? Actual cam angle or camshaft deviation?

 

I'm no professional tech but I do all the work on my car that I can because I enjoy it. I wouldn't consider replacing your lifters a DIY job due to the expense of the tools required to properly align the camshafts during reassembly. Exhaust lifters are simple standard hydraulic lifters but the intake lifters are a unique dual-stage design that can and do fail occasionally - and they are expensive. If you have a Durametric cable you can activate/deactivate the variocam high-rpm setting manually to give you some idea of whether it is lifter related. Since you were a tech then you already know all the tricks for resolving "stuck" lifters without disassembly but from your post I can't tell if the car sat for an extensive period of time before the misfires and tapping sounds. If not, then it's likely not just a simple fix.
I would also try using an automotive stethoscope to isolate the source of the sound and focus on the area where the chain tensioners are. When I had my lifters replaced my engine started making a horrible intermittent noise afterward but ran fine. The tech installed the timing chain tensioners incorrectly causing it to rattle against the case until it was resolved. Finally, since you isolated it to one cylinder bank a simple troubleshooting task is to just switch the hydraulic actuators between banks and see if the problems move to bank 1.
Sorry to hear about your issues and I hope they aren't a prohibitively expensive problem.

 

last time i thought i had lifted a lifter it was the impeller on the water pump wobbling on its shaft.

 

Ill take a look at the water pump when I get back to working on the car. Thanks for the info

 

good luck with it. a failing WP often has that scary "ticking" sound of a sticky lifter etc. i was nearly panicked until i self diagnosed it and replaced it.

 

Eh. if the water pump has started to sound that bad it's the shaft not spinning eccentric anymore and if that loud it will already be leaking coolant from the weep hole. Sounds different.

 

Im assuming its not the WP based on the fact that the sound has mostly disappeared after an oil change. I need to find the time to diag the bank 2 misfires so I can test drive the car.

 

I had a very similiar sound last year - a lifter had split in two

 

Have you had this diagnosed? Really expensive problem to have.

 

Might as well plan a "small" motor rebuild while you are in there.

 

OP you ever get this sorted?

What part #s did you go with? seems to be varying bits of information out there on this.