So, I just got my car back from having the engine dropped, my coolant pipes welded, a Guard Club LSD and a transmission cooler installed, and the GT2 clutch conversion done along with the PSM disconnect. After putting about 30 miles on the car, I drove it this morning putting another 15 miles on it, stopped off for a few minutes and got in, restarted the car and I hear a fairly loud ticking noise. Crap. Called my shop, they sent their mechanic out and confirmed it was the valve lifter on the #3 cylinder drivers side after listening to it with a stethoscope. I had a stuck lifter about a year ago when the car sat for about a month and it made the same ticking sound after being started but slowly went away as the engine idled and the oil warmed up to temperature. At the time I figured it was just some old oil that gelled up and caused one of the lifters to stick. Unfortunately this time around the ticking did not go away. I drove the car and all was normal with no check engine lights or codes but the ticking remained.

So, I am going to have to have the engine dropped, again!, and have the lifter replaced. Anyone have any issues like this before? The car is a 36K mile 2002 550 Rturbo so I'm running at a fairly benign power level but it does see the track quite a bit. Redline is set by RUF at 7200rpm but I generally don't run it past 6800 or so. Any suggestions here? I am assuming that it would be wise to swap out all 24 intake/exhaust lifter while there. Anyone know the correct part numbers as I believe there have been some improvements in the original lifters. Any help, thoughts or suggestions here will be greatly appreciated. Anything else that would make sense upgrading while in there? I just wish this problem surfaced when I had my car in the shop last week with the engine out... Really bad timing I guess with this problem cropping up 3 days after getting the car back with 4 track days planned over the next week. Oh well.... The good news is my shop will work overtime to turn it in 3-4 days, the gearbox cooler and LSD works like a champ, and I love the GT2 clutch....

 

that sucks

 

Thanks. Yeah, I know. Nothing to do but roll with the punches. Hopefully there won't be any other issues when the thing is opened up as it seems a number of cars have had an issue with the lifters which were redesigned by Porsche so hopefully the new ones will be the ticket....

 

wow. what a pita dropping it again. good luck with it.

 

Hopefully it's more of a light ticking vs. a harder metal tapping/knocking sound (failed IMS). Same side - same area.

 

Yes, it's a light ticking. The IMS is very quiet on this car. I had a couple of Porsche mechanics well versed in these cars take a look at and it's a sticking valve lifter. He listened to the motor with a stethoscope and isolated it to the #3 cylinder head area on the drivers side. Obviously there are 4 valves there so it's one of the 4. I'm just going to have all 24 replaced with the new updated lifters.

 

powdr, there is a part number of lifters on the older cars that are known to fail, I had planned to have mine swapped out during the rebuild. The good is mine didn't fall apart until Todd dissembled the heads, let me see if I can find the part number of the replacement.

 

The lack of any CEL and error codes I find a bit troubling.

A "stuck" (probably not stuck but unable to hold proper oil pressure due to a bad check valve) I would think would result in a subpar performing cylinder with a misfire as the result. (In this case the DME finds the cylinder is under performing and turns on the CEL and logs a misfire error code.)

A broken valve spring can sound like a "stuck lifter", as can a loose or in some way broken spark plug, as can even an exhaust leak.

Of course I'm not the pro and I'm not at the car.

Regardless the engine has to come out. I'm not aware these kinds of repairs can be done with the engine in the car.

IIRC the factory manual recommends that in the event of a bad say intake lifter, all intake lifters on that bank be replaced.

AFAIK, unless there's a TSB that I do not have access to (and I have access to none), there is no need to replace all 24 on that bank.

There is a risk that one of the new ones could prove to be bad. But with a reputable shop it should stand behind not only its work but the parts and if a new/replacement lifter proves defective out of the box or shortly after being installed you should not have to pay for the replacement of the defective lifter.

But of course it is up to you what you want to do. Replace all of the lifters or just the bad one and its brothers on that bank or even just the lifters of the noisy cylinder.

I have to touch upon this: It is not only important that the right oil be used but for cars that sit long periods of time unused that the oil be kept reasonably fresh even if the oil does not accumulate a lot of miles.

As the engine runs it gets contaminated with unburned gas and water. These not only dilute the oil and can also result in increased foaming both of which affects the oil to bear up under high temperature high load conditions, but when the engine is shut off everywhere there is any oil the oil begins to stratify. The unburned gas, water -- in the case of water loaded with other contaminates which combine with the water to form acidic compounds -- form layers and some of these layers are very corrosive. This corrosion can attack the very critical inner workings of the valves -- which are full of oil -- the intake valves especially which are very complex because they provide the low and high lift feature (combined of course with the intake camshaft that has the low and high lift lobes) of the VarioCam Plus system.

Sincerely,

Macster.

 

You are correct. It's not that the lifter is necessarily fully stuck but rather that it doesn't have the ability to hold oil pressure there by creating an increased gap which in turn causes the ticking sound. At least that's the way I understand it....
I was told by two highly experienced Porsche mechanics familiar with these motors that you generally won't get a CEL since the engine is not misfiring per se but effectively you have valve that is a bit out of adjustment due to the increased gap since the lifter is not holding pressure. I am sure if you let the problem continue to deteriorate over time resulting in misfires than a CEL would pop up. Oil in my car get changed every 3 months or less due to its track usage so corrosion should not be an issue. The engine does have to be pulled for this and the total job is about 16 hour. I am having all 24 lifters changed on the motor to the updated parts...

 

Ok, so the cam covers are off and camshafts are coming out next. Just as my mechanic told me, it is the #3 cylinder on the drivers side. Specifically one of the hydraulic exhaust lifters is bad. You can press on it and it collapses fairly easily so it looks like the internal spring is bad. Everything visible including the cam lobes look to be in perfect shape so that's a relief. Now they just need to pull the right side and swap out all 24 lifters and assembly can begin. Should be wrapped up in another couple of days.

 

it must inspire confidence when your tech makes a spot on diagnosis. I'd keep using him based on this one.

 

Good luck!

lifters look hard to access their condition while still obscured by the cams. I just checked a set to try to isolate a faulty one by trying to compress them in a vice. Crude and unreliable test but may expose a totally trashed one. All passed that test, but under load and full of hot thin oil with the valve spring pressure trying to colapse them one would talk occasionally.

 

I'm no expert but you could definitely see that the bad lifter was "soft" compared to all the others. You can reach past the cam and push on it with a pointer and it would compress an 3/32" or so while none of the others would. You can see the lifter behind the cam in the close up picture. The mechanic was explaining the workings of it t to me but it was a bit above my pay scale. He showed me a new lifter and there was no way to compress it by hand. The bad one he pointed out could be compressed just be reaching around the cam and pressing on it. Like I said earlier he isolated it initially to the #3 drivers side cylinder valve by listening with a stethoscope but obviously could not pinpoint which one of the 4 lifters until the cam cover was off. Basically my understanding of it is that the lifter is "tired" and not holding pressure and as a result you have a gap that is created between the lifter and the cam lobe which in turn creates the clicking sound. Hope that helps...

 

Good to know it was just one lifter.

The lifter -- I have a plain lifter -- not a VarioCam plus lifter and a VarioCam Plus lifter at my office desk -- doesn't everyone? -- and each lifter, well, the zero lash part, has a check valve that is supposed to let oil flow in in one direction (high pressure oil from the engine oiling system) and keep oil from flowing out that direction when the lifter is under pressure from opening the valve. This keeps the lifter body/zero lash adjuster full of oil with no air bubbles/pockets. The oil which being incompressible keeps the lifter body face in very close proximity to the camshaft lobe so there's, well, no lash, no clearance of any significant amount.

Also, I agree with another poster. You have a pretty good tech. Kudos to him and you.

Sincerely,

Macster.

 

Your mechanic might find that as soon as he removes the intake camshaft>> more than one intake lifter "just falls apart" Without pulling the camshafts out, one doesn't see the guts of the buckets. Also, please inspect the "three" oil control rings for the actual vario cam module. If there is any wearing or grooves present REPLACE them. I'd add the covers and three new sealing rings on each of the intake camshafts to my replacement parts list.