constant valve lifter noise ok?

Hi all, I'm a long time lurker with a high mileage (85K) '99 996 that has recently developed a pretty noticeable engine tick that actually seems to get a little louder when the engine gets warm, and it doesn't go away. The car runs fine and pulls great. My trusted independent mechanic says no worries, it's just lifter noise which isn't a problem. Just want to get your opinions, should I believe him or am I in for a new engine soon? thnx in advance.

Are you sure it is lifters and not a noisey EGR valve? That valve will click continuiously sometimes. It is the valve directly above the alternator.

it is the EGR, should I be worried? the ticking is constant, not rapid at idle but gets more rapid up and down with acceleration and deceleration. Thanks

That is normal opertation for the EGR valve. Not to worry. So much for trusting your mechanic. Glad he didn't suggest tearing apart the engine to install new lifters....only to have the noise continue after he was done.

Now I can spend my dough on more mods

Nice work 1999Porsche911. I know a lot about my MY 99 but you've got answers to stuff that would have left me scratchin' my head.

Porsche tech says it could be a debri in the hydraulic lifters that partialy blocking full flow of the hyd fluid to properly lift the valves.

and changed the oil hoping it would help, which it didn't. If it is the valve lifters, I wonder if a higher oil viscosity might work.

I know on the 993 that this is not uncommon and due to a partially collapsed lifter. If it is a lifter and it is always noisy, then replacement is the only fix. Everything else is just a band-aid that falls off. Does anyone else know if the 996 has had a history of failing lifters? Marv

Is this a serious issue? Do you guys think I need to take care of it asap, or can I wait a bit? thanks

I thought you said that you confirmed the noise was the EGR valve and not the lifters. You should not have noisey lifters at 85,000 miles.

Is the EGR system located where you can get at it with the engine running? If it is, you can use a long socket extension as a stethoscope. Compare the noise there to the noise at the valve cover (or use a real stethoscope). You should be able to localize the noise.

Just open the trunk and unplug the valve. It takes less time than checking your oil level.

1999porsche911, would you be able to tell me where the connector is located at in the bay? Thanks again for all your assistance.

I am in Florida right now so I do not have a picture, but the valve is directly above the alternator and is connected to the throttlebody with a hose. The other end connects to a hose going along the leftside of the engine toward the front. There is only one electrical connection to this valve. Simply press the wire clip on the connector and remove. You will get a CEL because the valve is disconnected, but it will reset in a few days after you reconnect it. When you hear the ticking sound from your engine, stop, open the trunk, disconnect the valve connector (with engine running). If the ticking stops, you have found the noise maker.

Turambar, did you ever confirm your ticking source?

It was...... spark plug with the terminal end broken off! I've been running on 5 cylinders this whole time and didn't even notice it! Luckily there doesn't seem to be any permanent damage, knock on wood.

How big a pain in the butt is it to change a lifter on a 996?

It is pretty involed and takes some specail tools, although you can fabricate them yourself and if your are inclined it is a DIY. Harder to do with the engine in the car, but not impossible. You have to take off the cam cover and the cams. You need a tools to lock the engine at TDC, but a pice of rod the right size will do it. Then a tool to hold the cams in place as the cam cover is part of what holds them in place. The tool goes for $200+ but you can fabricate on for only about $10 in materials. I have a drawing if you need it. Then you need another "special tool to hold the cam advance tensioner, again this can be made out of a piece of threaded rod for less than $10. Also "specail tools" to hold the cams in place when you remove the sprocket and tensioner, again I used some aluminum stock to make a tool. Once the cams are off then the lifters come right out. Technically you them need special tools to set the timing of the cams, but there is a shade tree mechanic way to mark the timing of the cams to avoid this. Again, I have done it. New lifters cost about $50@. For 3.4's the intake and exahust lifters are the same, with 3.6 variocam plus the intake and exhaust are different. Another option is to send them to Flat 6 and they will rebuild/modify them, don't say exactly what they do but they say it will eliminate the problem. Cost is about $200 for all 12 intakes, and about $200 for all 12 exhaust. Let me know if you are going to try it and I can give you some advaice/pointers.

We alter the internal valving of the lifters and make changes that help them resist clogging in the future that makes them not function correctly. I use these lifters in all the engines I build.

Dharm55, Thanks for the info. I have the cdrom manual. If I tackle this I'll give you a holler. Own a machine shop so I should be able to make the tools. Might be selling the car due to need for a bigger car cause my wife got accepted into a grad program and now i'm gonna be carpool dad. Thanks for your reply. Cheers, Geoff

Turambar, don't worry about all this, almost 100% it's your EGR, it ticks on everyone's car and the question has been asked a bunch of times on this forum.

Sheesh another 4 year old resurrection...nice, though, because I wasn't aware of the loud ticking of EGR valves on these cars. Does replacing the egr valve usually remedy it if you want to kill the noise?