duydle

:help: I need your advice on the following tire and wheel sizes for 996TT. Front Tire/Wheel : 235/35/19 and 19x8.5 Rear Tire/Wheel: 315/25/19 and 19x12 I already have the wheels but am now ordering the tires from TireRack. They're telling me that the rear wheels 19x12 will not fit 315/25/19 tire. Is he correct? I know that others have done this before and had no problems. Please advise.

Thanks Loren!

Matt - It's been a while since I got back to this thread but the clicking noise that was coming from my engine was actually a bad idle pulley and it caused the belt to start slipping. Took it the dealer and it costs $600 to replace the pulley and belts, plus 3 hour labor. Another $300 to have it towed on a flat bed for 75 miles to the dealer.

Recently when I drive over bumpy roads, my front hood latch keeps popping out. I can even open it from the outside by slipping my fingers in the small openings and pulling up. Does anyone know how to fix the latch?

There is a lifter for each valve and what a lifter is is and cylindrical housing that has a small barrel inside of it. You can google and find pictures. This barrel is tight against the valve housing and has engine oil under it which ceates a hydraulic effect when the barrel is pressed down into the housing. This oil is constantly drained and replaced with engine oil as the lifter cycles. Sitting against the top of the lifter (barrel) is the valve stem. The lifter if moved up and down by the lobes on the cam. As the lobe on the cam lifts the lifter, the valve stem is tight against the barrel in the lifter and causes the corresponding valve to open. The oil inside the lifter keeps the barell snug against the valve stem so there is constant contact between the 2. As the cam lode releases the lifter and it moves away from the valve stem, the hydraulic pressure created by the barrell pressing up against the valve stem pushes the barrell back up to the top of it's stroke, again, keeping the barrel snug against the valve stem at all times. (Like a sping would) When you hear valve noise, it is tippically a result of the valve stem not keeping constant contact with the barrell in the lifter and the noise you hear is the stem hitting the barrell. The most common casue of this is insufficuent hydrailc pressure build up in the lifter which does not allow it to maintain contact with the valve stem. It can also be a result of other things, but this is the common cause. Now, when the barrell is squeezed down into the lifter housing, some oil is allowed to be pushed out of the housing. The speed at which this bleeding occurs directly effects whether the stem and lifter stay in contact with each other. If the oil escapes too fast, there will not be enough oil to maintain contact. This is why you hear more noise with a bad lifter at slower engine speed. An oil that is too thin will bleed faster that will a thcker oil. Further damage can occur if you do not have sufficient pressure is that this will allow the barrell in the housing to cock slightly, scoring the side walls and eventually lead to athe barrel getting stuck in one position. Thanks for your explanation! I found the original email posted by the Keyvan and he said it was a blockage in the oil system. They drove the car around it until it was unblocked!

I checked my oil level and it was fine, up to the second to highest bar. If you don't mind me asking. What is a lifter and what exactly is it's function. I just had my oil changed at 29K with 10W40. Hearing about the engine rebuild doesn't sound very good.

Keyvan, what did that sound turn out to be? Is it normal? Thanks Keyvan, My 01 TT also sounded like this when I pulled my car over the road after hearing the same sound as what you posted. My car was towed to the nearest Porsche dealer and is waiting to be looked at. Does anyone know what could be causing that sound? Thanks!

Thanks djantlive. After searching different threads on this top, I'm encouraged to find out that many people have DIY.

I'm a newbie to this forum and would like to know how many of the 996 TT owners out there have actually done their 30K Maintenance on their car before? I just called my local Porsche dealer in Bellevue, WA and they quoted me $1800! Can't believe how much this costs! So I'm determined not get ripped off and do it myself. For those that have DIY, how difficult is it and what's the approximate costs of DIY? I'm up for an oil change (currently 28K on my car) and they quoted me $300. Oil change should be pretty straight forward after visiting the DIY section but I'm more concern about the 30K maintenance and how much effort it will take. Any advice would be greatly appreciated. :D