Litre Carrera 2 4 from 1990

This model superseded the 3.2 Carrera, having slightly smoother styling, a bigger engine, power steering and ABS, the Carrera 4 having 4 wheel-drive through a front transaxle. The turbo charged Turbo 2 example is quite awesome.

They are a big all round improvement on the older 911, bringing the drive and comfort more into line with the quality of the original 944, while maintaining the mystique and thrill of a traditional 911. They have a revised exhaust system that sounds just fabulous. An interesting option is the Tiptronic, 4 speed sequential gearbox, making automatic driving more sporty and fun again with very little loss of performance once the car has got away from a standing start.

The introduction of ABS was a major step forward since the age-old danger of spinning the tail end of a 911 under braking (due largely to the very light front end locking up and the weight transferring to the rear as the front slides out sideways) has been severely reduced and safety has been greatly enhanced. The application of a 4 wheel-drive option has further improved the safety features although many find the Carrera 2 the perfect blend between the old and the new. The first 3.6 engines (the 964 Carrera 2 & 4) are very powerful, responsive and fast incorporating a number of technical changes from the 3.2. They seem reasonably reliable, but are more time consuming to work on and servicing costs are therefore higher.

Things were improved with the 993, so while the 964 range are fabulous cars, we have increased the prices of our Lifetime Maintenance Plan for the 964 to reflect the extra time taken servicing them. There are for example twice as many spark plugs than the older 911's and it is necessary to remove the under-trays and exhaust system to gain access to the lower row of the twin spark plugs for each cylinder or to adjust tappets. Many examples we see have not had these lower plugs replaced by the last service centre. Consequently service prices are higher and because many cars have not been properly serviced (to avoid these costs) additional problems have emerged.

A change was also made from solid gaskets to recessed rubber seals in some engine joints, which work well for many years and improve accessibility and strip down times. However they eventually need replacing. Although the cylinder head sealing system on the 3.2 Carrera was reasonably reliable, the additional bore size rendered the 964 prone to oil leaks through the cylinder head joint face. Porsche modified this design later with new revised cylinders and heads and a wills type-sealing ring - but for many the cost of these replacements is prohibitive. Also the cylinder base seals were vulnerable. All this combined with a power steering shaft seal that has limited life have rendered these cars likely to leak some oil as they age. Unfortunately, even when they have been rebuilt they are not always oil tight. We modify the cylinders to accept the later head gasket sealing rings - which greatly improves sealing but still they sometimes eventually leak a little. Higher mileage cars would benefit from new big end shells when the "top end rebuild" is considered -developing into a full engine overhaul.

Despite this, the basic engine is superb and we expect that, if they are properly looked after, they will prove mechanically as reliable as the previous models. However some electrical problems are beginning to emerge that are quite complicated due to increased sophistication. Usually the fault is easy to put right once the reason has been worked out but they can be very time consuming to solve. Often the computerised diagnostic systems reveal a fault but not the real cause and circuit diagrams have to be traced and analysed to work out why the diagnostics got things wrong. Sometimes a proprietary alarm/immobiliser system will handicap the diagnostic process. If the battery goes flat it is necessary to download software from a Bosch Hammer to enable it to run properly from tickover. Later cars (like the 993) incorporated this software into the car's computer to get round this. Some problems with unstable tickover are beginning to emerge that have a variety of causes that will no doubt be resolved in time.

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