In many cases, even with the head off the engine, the scoring cannot be seen until the piston is removed — it can be way down at the bottom of the cylinder below the lowest point the rings meet the walls. Sometimes it can be seen by scoping down the spark plug tube, but the best view without disassembling the engine, comes from removing the oil pan and scoping from the inside.
Timing is everything; especially in comedy and engines! The opening and closing of valves, the piston rising and falling in the cylinder and a spark are required at precise times during an engine rotation.
The major moving parts are connected by chains and these ensure the relationship between those moving parts is maintained regardless of the rotational speed. The rotation is measured in degrees of a full circle. So, for example, at degree zero; piston 1 should be at the top of the cylinder and the intake and exhaust valves closed. This is known as top dead center or TDC. Naturally over time, the components supporting those timing chains will wear — the chain itself, guide rails, tensioners etc.
The engine management system is measuring the angles in every rotation and within a range of angles, can adjust the timing of fuel delivery and spark to compensate for wear changes. However, extended wear can produce an angle outside of the allowed deviation range and a fault condition will be set. The earlier Boxster experienced issues with stretching timing chains and significant wear on the timing guide rails.
This caused a nasty rattle at startup and generally set faults during acceleration. Most of these issues were corrected in later cars, but during the life of an engine you should expect that these vital timing components will wear.
You need a clear picture of where the used vehicle you propose to buy is in this wear process. A competent Porsche repair shop can tell you what the deviation angle between the cam and crank is during a used car inspection. This is a simple read from a diagnostic device and a clear indicator as to the health of the engine timing. The change in angle will affect performance and is almost certainly not something you could pick up on during a test drive of an unfamiliar car.
Replacing the chains, guides and tensioners to correct this problem is not an inexpensive proposition — it is however, relatively straightforward if your budget allows. Before buying any car, it is essential to be certain when the last time the engine management fault codes were cleared and to check the status of the emission monitors. Again, this is easy for a competent shop to check or indeed the DIYer using a handheld scanner. How hard has the car been driven? Taking the engine to the red line for RPM is a good thing, but going over the red line obviously can cause damage.
A gear change at red line will actually cause the revs to increase slightly momentarily — nothing bad here. But, if you select the wrong gear, the engine revs to go way over the red line. Thankfully, Porsche engine management records many things and one of the most significant is known as an over-rev situation.
Data is permanently stored within the ECU showing running hours and when engine events occurred. There are six levels of over-revs recorded ranging from the engine being red-lined through to what would be a potentially catastrophically high RPM event. Events in the first category suggests the car has been properly exercised, but events in the higher categories could be hiding a potential life shortening engine event. Many Porsche owners like to go to track days.
On the track, gear changes will occur right around the rpm maximum red line. These events will be recorded if they reach the lower levels of the over rev counter. Multiple recorded events in the lower over-rev categories could be a sign of how much track time the car has experienced. We recommend you use the help of a Porsche Repair Shop to read this data and give you an assessment. There are some common areas where oil leaks occur on the Boxster engine. Most are easily fixed and are part of the normal wear and tear process.
One of the most common areas for an oil leak is the engine rear main seal. See our common problems page for more information. Leaking oil used to just be seen as a annoying stain on the driveway and a potential fire hazard. However, modern cars feature many electronic engine management systems that can potentially be severely damaged by oil ingress.
Oil leaks should not be a barrier to purchase, but they should be considered in terms of the purchase price — what appears to be a minor oil leak could turn into an expensive job.
Again, this is where a competent shop should be able to accurately asses and relay the cost of an oil leak repair. An integral part of the emissions system, the Air Oil Separator AOS is designed to extract oil from gases in the crankcase, recycle the oil to the sump and send the gas through the combustion path to be burnt and cleaned by the catalytic converters.
The AOS has caused numerous issues on Porsche engines. As the membrane in the AOS fails, oil is sucked into the air intake. Initially this can show up as a check engine light for fuel adaptations and the oil can be deposited on the o2 sensors and cause emission faults.
Of course, once it fails completely and oil is sucked into the intake, the resultant huge clouds of white smoke are fairly obvious. However, replacing the aos sooner, rather than later, is a good precaution. A failing aos is the likely cause of rear main seal failure, as it is in other VAG cars. Crankcase gas is not extracted well enough, pressure builds in the case under acceleration and escapes out of the rear main seal causing seal failure and the resultant oil leak. A failing aos also causes oil pass into the intake and will cause the engine management to adjust fuel mixtures.
The changing mixture can cause over fueling and lead to other more significant problems. Check to see when the last replacement of the AOS was completed on the car you plan to buy. If there is no record, plan to replace it as a precaution. Make sure you spend time checking the operation of the roof to ensure it goes up and down smoothly. Most of the top issues are usually simple and inexpensive to fix, but can be annoying if you only discover them when you want to drop the top on your first sunny day.
Porsche revised the mechanism that operates the top a few times during the life of the Boxster. Older original versions of the mechanism have parts that cannot be serviced. You then can listen to a playlist created based on an amalgamation of what all your friends are listening to, which is also enjoyable.
Those concerned with privacy will be relieved to know you can prevent the public from seeing your personal listening habits if you so choose. Email will not be published. Where can I buy a Porsche carrera gt in los Angeles? How reliable? I am either going to buy this years model or maybe a used How long do you think boxsters last, i. Comments 13 Posted in Porsche. How long does a engine last? Share More sharing options Followers 0. Reply to this topic Start new topic. Recommended Posts.
WilliamsF1 Posted May 11, Posted May 11, Hi' I was wondering How many kms do you think is the typical lifespan of a 2. And what is the price of a new one if a engine breaks down?
Kind regards Morten. Link to comment Share on other sites More sharing options Posted May 11, edited. My parents have had VW Ventos that went Thanks again for the reply Edited May 11, by WilliamsF1. Rodger Posted May 12, Posted May 12, Do you really need to know how long they'll last? Beanoir 1, posts months. Aim for 15k and i'd say you won't be far wrong. Early indication on mine is that the 19" P Zero are going to give rear and front, unless the wear rate changes as they bed in.
The Michelin Pilot Alpin winters in the same size look like they're wearing at less than half that rate. Although IIRC winters have to be binned at 4mm anyone know? Hope this helps. Reckon it's probably less that you were expecting! MadMark 1, posts months.
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