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Hi John, 

The Atkinson engine is a type of engine invented by James Atkinson in 1882. The Atkinson Cycle is where the stroke of the piston can very in length across the four cycles in a four-stroke internal combustion engine. The length of the stroke during the power cycle is increased to promote efficiency, but because this comes at the expense of a shorter intake stroke there is some loss of power and therefore this engine design is best suited for use in hybrid systems where the electric motor can make up for some of the loss of power. 

In conventional four-cycle petrol engines, fuel enrichment is sometimes necessary to cool the exhaust gases, preventing degradation or destruction of the catalytic converters. In an Atkinson cycle engine, compression and expansion are not symmetrical, and the valves close late, delaying compression. This creates a high expansion ratio for less compression, reducing intake and exhaust energy losses and converting combustion energy to engine power more effectively. As a result, the exhaust temperature is lower than that of conventional engines.

The current model Toyota Prius Hybrid uses a 1.8-litre Atkinson Cycle engine. Adopting the Atkinson cycle and a cooled exhaust gas recirculation system brings significant gains in fuel efficiency and emissions reduction.

Prius 1.8-litre Atkinson Cycle engine

Because the intake valves close late in an Atkinson cycle engine, compression is delayed. This creates a high expansion ratio for less compression, reducing intake and exhaust energy losses and converting combustion energy to engine power more effectively. As a result the exhaust temperature is lower than that of conventional engines. Cooled Exhaust Gas Recirculation reintroduces the cooled gas into the intake system, further reducing engine operating temperatures.

Other models to use Atkinson Cycle engines include the Lexus CT200h, Lexus RX 450h, Mercedes S400 Blue Hybrid

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Hi Gar,

We are never short on opinion here at CompleteCar.ie Gar, so you have come to the right place. Coming out of your 5 Series you are going to have to buy something that is vaguely interesting or you are going to really hate whatever you buy. Given that you are concerned about reliability you are right to express some concerns about the Passat. Unfortunately there have been quite a few issues with the last model Passat and it would probably stop me buying one second hand, even though it is usually the default choice. I'm not sure why you mentioned the Rover 75, but lets pretend that you didn't.

If I was buying something with €8,000 - €9,000 I think it would probably be a Mazda6 Diesel. I really like them and they age really nicely. 

Here is a decent example: 

You would have to check the DPF is ok, but otherwise they are a cracking good car. 

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Hi Tariq,

Given that these cars would both have electric seats with a full range of motion, your height will not be an issue. Perhaps the Range Rover would provide better visibility.

Either way, your height shouldn't be any sort of factor in what car you choose as most are designed for a wide range of driver sizes.

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Hi Jim,

Personally I have never really been a major fan of the footbrake on the Mercedes-Benz cars, but I wouldn't say that they are hard to manage. They just take a little while to get used to. It certainly wouldn't be a reason not to buy one

The electronic handbrake on the BMW has been very reliable so far, but they again it hasn't really been around long enough for any major problems to surface just yet.

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Hi Linda,

It certainly does sound like an injector issue - assuming the coil and plugs are fine. We'd suggest that the injectors are tested before hastily replacing them. Any decent garage will do that for you - it doesn't have to be a main dealer. From the information you've given us about the car, we don't believe you can re-program the injectors. It may be possible to refurbish them, but in most cases it's probably better just to replace it.

If that's what is needed, the cost of the part itself is well over €100, but no garage should charge you more than an hour of labour for replacing it, as it's a relatively easy job.

Hope that helps and you get sorted.

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Hi Michelle,

With a car of this age it's not surprising that something may have worn out. Without knowing the mechanism of the 306 CC in depth we would never hazard a guess as to where the problem lies. Without doubt your best bet is to bring this into a Peugeot dealer to get their opinion. The service manager may know of a common problem and quick fix so talk to them before committing to any work.

If you have no joy, please come back to us.

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Hi Ronan,

We asked Ciaran Lowe, a former service manager for Nissan Ireland, to answer this one. He told us. "I can understand your reasoning for removing the Diesel Particulate Filter (DPF) because of the excessive cost of replacement. However, the DPF on diesel vehicles plays an important roll in reducing vehicle emissions. In fact these filters can reduce diesel soot emissions by up to 80 percent, so by removing the DPF it is interfering with the emissions on your vehicle. By re-mapping the ECU it is only tricking the engine management  system to see emissions within spec regarding the DPF system. However even with the ECM re-mapped the vehicle will still fail any future emissions tests. The fact your light is on indicates the system has identified out of range emissions."

I'm afraid the best solution all-round is to seek a used DPF filter.

We've talked to a few people in the industry and short of messing with the actual lights in the dashboard there is no way around this. We can't recommend this route, but it could be done by any auto electrician.

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Hi Sharon,

Earlier Renault Méganes were not without their problems, but the latest ones have improved a lot. If you could let us know what year your Mégane is we can investigate your problem with Renault and see what they say.

Let us know.

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Hi Danny,

We've spoken to a few experiences mechanics and they've not come across this problem, all saying that the 1.9 TDI engine in general is very reliable. It does sound like an electrical problem though, so the easiest way to trace its cause is to bring it to a mechanic that has a proper diagnostic system. It should pinpoint the issue. It may be just a sensor or loose wire or something.

Here's hoping!

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