intofx

Drove around the block before putting my 04 C4S in the garage and heard a loud ticking from the rear of the car. I'm leaving town for the Holidays today but when I get back need a good reputable shop to take a look. I'm in Los Angeles (San Fernando Valley). Any suggestions or am I just better off going to the dealership? In the event this is an IMS failure, I'd love to find someone familiar with the upgraded LNE parts. I searched and came up with very little info...

Here's a sound clip I recorded. I have since shut the car off and will not crank until someone looks at first. No engine lights, no leaks...

http://www.dailypost.tv/graphics/Sound/PorscheSound.aif

TIA

LVDell

Temp outside?

Oil type and weight?

Sounds like lifters.

ivangene

+1 for lifter noise...

intofx

Assuming this is a lifter issue, how difficult is this repair?

LVDell

See post #2

Could be as simple as the temp and/or oil.

flyingpenguin

Take a look at this post on renntech.org:

http://www.renntech.org/forums/index...6&#entry163696

JP

trackjunky

Might be a chain tensioner. Another local guy had a similar sound and after a flush and refill - PRESTO! - problem went away.

Don't ask me how the shop did it.

Macster

Noise doesn't sound all that bad.

A car that sits unused for a long span of time (week or more though it varies based on engine internals, state/condition of oil, etc.) can develop a tick that appears upon cold start and can stay around for a few minutes at idle.

A zero lash lifter can collapse and fail temporarily to pump up with oil. A chain tensioner can bleed down and again fail to pump up with oil right away.

An injector can get noisy.

These engines have a lot of reciprocating parts and cold an engine is just noisy. You may have been hearing something normal.

How fresh is the oil? Oil with some short trips and no real hot running can really develop a load of water and unburned fuel which tends to make the oil thinner and the engine noisier upon startup. This oil tends to run out of or be forced out of areas like the zero lash adjuster and chain tensioners more readily too.

Is oil the right viscosity, a fully synthetic oil, and a quality brand of oil recognized by Porsche as suitable for use in the engine? No 10w-20 discount oil in the engine I hope?

An oil change might be called for.

Lastly, my Porsche tech tells me that for cars that sit around with little use a Swepco oil additive (505 IIRC) can help cut down on the noise these engines make when started up. Cutting down on noise also reduces whatever wear the noise represents. (I did an analysis of this additive and it contains 200ppm of molybdenum, an anti-friction additive.)

Sincerely,

Macster.

Pac996

Try starting then adding a little more idle for 5 seconds or so in the range of 1,200rpm or so to get oil flowing good at start. Saves engine life getting the oil in position.

Headers leaking where they attach to the head will give the same noise. It doesn't need to be persistant. Temp changes can very when the leak is. My old 71 camaro with super comp headers would always loosen up then tick tick tick. Then same old wrench I'd have in the car ready for the game would shut it up. Then all I'd listen to is the .513 lift with 306 duration cam rocking hehehe. Talk about a low vacume. Oh yah try tinkering with seeing if any header bolts have gone loose. Many white gaskets need to be soaked in water before exhaust manifolds are bolted down. It makes them expand so it's a super fine fit when bolted down. If not eh. Torquing the engine around doesn't help keep the headers sealed tight either but....impossible to stop in almost 40 years of driving. Anyway, don't forget exhaust leaks at the header can sound exactly like a lifter going wrong.

So besides what's already been mentioned that's about all I can add. Good luck with it.

Jake Raby

Lifter.
Since it was more pronounced on the passenger side it is probably going to be on cylinder #4. This cylinder has the most lifter issues due to the oil system routing and the fact that is generally receives less oil than the rest of the cylinders valve train wise.

That lifter sounds like it has completely failed, lifters that are not pumped up thoroughly or have become dirty do not sound quite that pronounced.

Its not a bad fix, just takes time, common sense and a couple of special tools.

1999Porsche911

Change the oil and see what happens. Put in something better than Mobil 0W40. It is common that a lifter may get stuck at times and does not mean it will not return to proper operation by itself.

Jake Raby

These lifters have only one inlet, meaning oil doesn't pass through them. Because of that once a lifter becomes clogged/ obsructed its damn near impossible for it to return to normal from just changing the oil or flushing the system. You might get lucky by changing the oil and solving the problem.. If that does work IMMEDIATELY go buy a Lottery ticket.

FYI- The noise coming from a stuck lifter has nothing to do with it's orientation within it's bore or if it is rotating or not.. The noise comes from the hydraulic piston not "pumping up" creating valve lash which leads to the noise..

Pac996

Remember you can check the bolts attaching the headers at home and save a lot of costs. I haven't met too many people that know leaking headers will make the same sound as a lifter. Very quick fix and might need the bolt backed out and cleaned since firing exhaust near it can powder it like lube. Hopefully you didn't get a super cold batch of water that cracked some a header or head. I'll stay away from that sort of talking.

1999Porsche911

First of all, the lifter still breaths and fresh oil is both moving in and out as the engine runs. Secondly, the noise could be from any of a dozen things, including electrical arc, pulley, cracked plug, low oil pressure, temporary blockage, exhaust leak, injector, etc, so trying to scare this guy into thinking he needs a new lifter, whether it turns out that way or not, is neither a smart nor professional diagnosis based on a low quality sound file.

Jake Raby

If the lifter becomes clogged/ obstructed oil cannot move into or out of it due to the obstruction and the fact that the oil does not pass through the lifter. When these lifters become clogged they simply stop functioning amd once the obstruction occurs its a bit late.

Ever tried to free up a completely clogged drain with drain-o before?? It works well on partially clogged drains, but not those that are completely obstructed.. Same goes here, especially when the oil feed orifice in the lifter is less than 1mm in diameter.

Based on that sound file and the fact that I have heard no less than a dozen of these same sounds in the past two months (that were bad lifters) I am confident the noise is a lifter. I'd not make such a statement without great confidence because of people just like you. (Of course you'd love it if I were incorrect-)

Have you ever held an M96 lifter in your hands???