Variable Geometry Turbo (VGT) Systems

VGT systems, otherwise known as Variable Geometry Turbo Systems and Variable Nozzle Turbo boost control systems have been installed to a majority of diesel engine vehicles since the beginning of the 1990's. One feature of the control system is the variable turbo boost control, this has been designed in order to minimise "turbo lag" and to also provide a nearly constant turbo boost pressure at all engine speeds. The turbocharger in the boost control system has been fitted with a finned diffuser piston which in turn is operated by a vacuum controlled capsule, this allows you to achieve and obtain the turbo boost control effect.

Developed to increase the speed of the exhaust gases which strike the exhaust turbine at reduced engine speeds, the finned diffuser piston can also be changed to minimise the speed of the exhaust gases which strike the exhaust turbine at excessive engine speeds, this is done by changing the angle of he finned diffuser on the exhaust turbine.

At low engine speeds, the diesel engine management system control module (PCM) provides a control signal to a vacuum solenoid valve, this valve then opens which allows vacuum to be applied to the controlled capsules; this then leads to the finned diffuser piston being pulled towards the boost pressure control piston. When this takes place, the cross-section area between the exhaust gases and the exhaust turbine is closed, allowing the exhaust gases to pass through narrow cross-sectional areas before passing through to the exhaust turbine. Leading to an increase in the speed of the exhaust gases passing across the exhaust turbine, which in turn also increases the speed of the intake air turbine and increases the rate of boost pressure at  low engine speeds.

However on high speeds, the vacuum is released  on the vacuum controlled capsule. The finned diffuser is pushing open due to the spring tension inside the vacuum controlled capsule. When this happens, the cross-sectional area between the exhaust gases and the exhaust turbine is fully open. This then allows the exhaust gases to pass through a much larger cross-sectional areas before passing through to the exhaust turbine. This reduces the speed of the exhaust gases passing across the exhaust turbine, which in turn reduces the speed of the intake air turbine and reduces the rate of boost pressure at high engine speeds.

A Bus Company in China teaches it's Drivers not to Crash into Supercars

Bus drivers in China have been instructed explicitly not to hit supercars, and to that end have been shown posters featuring the badges of various supercars... to help them remember.

Yep, according to Car News China, the average bus driver in Jinghua couldn't tell a Ford Focus from a Ferrari F40.

But now they have no excuse, because they officially know what the badges look like and how much the cars are worth...

This means that prior to deliberately accidentally squeezing through a ridiculously tight space, the driver can think, 'but no, this car is worth five million yuan...I'll hit that Kia instead.'

Car News China says that the insurance policies usually only cover a fraction of the cost of a typical supercar, leaving the remainder of the bill with the guilty party. It means that, were a bus driver to sleepily trundle into a Bugatti Veyron, the bus company could end up with a liability running into millions.

To educate their drives the bus company has filled their offices with posters explaining to their employees “Not what to hit”

The posters were hung on the walls of the company’s offices and serve as a warning to the bus drivers to be very careful when they see a supercar coming around. On the poster the logo’s of various supercar makers and the price of their automobiles. The drivers were called in a meeting and literally educated like a bunch of children on the financial dangers from a bus-supercar crash.

Luckily in the UK, Bus drivers and motorist are a little more careful with their driving, but just in case you come across the occasional idiot, Megavaux will give you the peace of mind that you can repair your Vauxuall cheaply and safely.

The price of replacing car parts...

Aston Martin admirers should take note of this story and possibly feel glad this didn’t happen to them.

A £175,000 Aston Martin DBS lay broken in one of the most exclusive areas in London after thieves targeted the luxury car’s wheels. The car was left stacked up on bricks in Eaton Square, Mayfair earlier on this week.

However, it seems as though the thieves’ scheme to take all four wheels from the car was foiled as pictures show the driver’s rear wheel was left on the car with a rather contorted jack poking out from underneath the car. The metalwork around this wheel was also left damaged.

An Aston Martin expert estimated that the damage could cost up to £30,000 to fix, with the wheels are tyres alone easily costing £4,500 to replace. The body repair work could cost up to £3,500 and as the car was not properly suspended when the wheels were unceremoniously removed, there could be damage to the brake discs which could cost the owner several thousand pounds to repair with one newspaper suggesting a figure of up to £20,000.

In spite of wishing we could afford a posh car like the Aston, at Megavaux, we’re pleased that the Vauxhall parts we supply are available at a less heart-stopping price!

Why I love my Vauxhall Corsa

This is my Vauxhall Corsa. Her name is Vivienne and she is 14 years old. Funnily enough, I’m not much older than the car!

Vivienne has a 1.2 litre engine and probably missing most of the horsepower she was born with. Sometimes I wish she was a little more ‘gutsy’, but when you buy a small car because you a.) can’t afford the insurance on a bigger car and b.) don’t have 2.4 children and don’t need a big estate car, there has to be some give and take!

I’ve had my Vauxhall Corsa for almost 3 years now and she is just as lovely today as the day I first decorated her with flowers. My Corsa might be old, but unlike my first car, a dilapidated Peugeot 106 with four gears and a manual choke, Vivienne has been reliable. She has refused to start on only two occasions – both because her engine wasn’t turned over for two weeks. She’s never failed an MOT, although the garage has provided me with short lists of advisory things to do. This is fair enough as all vehicles require maintenance. Whether your car is old or new, you can’t be complacent about keeping it running properly as demonstrated in this article about the need for car maintenance.

My Vauxhall Corsa is reliable because I look after her. I love the freedom my car gives me as it means I can go where I want, when I want. As I live somewhere relatively awkward, I can’t rely on public transport to get me to work or to the supermarket for a week’s shopping. Because of this, I need my car to be reliable and my Corsa is exactly that.

Maintenance really is the key to keeping your car running smoothly, how else could my 14 year old Corsa be in better shape than my boyfriend’s 6 year old Seat?

Here are my key tips for keeping your car working well for you well into its dotage:

• Check oil and water regularly. The moving parts in the engine need to be lubricated so low oil levels can cause damage to your engine.
• Check your tyres. Low pressure increases fuel consumption as well as making your vehicle less responsive when you need it most.
• Get strange noises looked at as soon as you notice them. I ignored noise at the back of my Peugeot for weeks and one day, the exhaust pipe just fell off!
• Clutch control is very important. You could drive without a clutch but you would ruin your gear box and that is a big job for your mechanic. On my Vauxhall Corsa, there is a little clip on the cable that stops it from ‘slipping’ and snatching from you. However, if you’re heavy-footed on the clutch, you could wear the cable – again, on my Peugeot the cable just snapped because I was using it far more than I should. I have learned my lesson now.
• Go down to your local breaker’s yard. I always go to Megavaux for spare parts for my car because they know their Vauxhall car parts, they’re really good guys there and its much cheaper going to Megavaux than going to a cowboy mechanic who charges you for work and parts that they haven’t done or used!

January News

January has been a nightmare for drivers thanks to the devastating snow and ice, grinding the UK to a halt. With stories emerging that temperatures hit -16 in parts of Scotland, we have certainly learned the weather is a harsh mistress and that in the UK, we are poorly prepared!

Drivers were stuck in their cars for hours at a time and we happily echo advice issued by the emergency services – only make essential journeys in your car in such extreme weather conditions. We would also say that if such weather is predicted, carry a ‘survival pack’ in the boot of your car consisting of the following items if at all possible:

• A large bottle of water
• A flask containing a hot beverage
• A reflective jacket or reflective strips that can be placed on your person should you be required to leave your car
• Blankets
• Snacks to keep you going just in case you are stuck for hours
• Fully charged mobile phone so you can inform loved ones that you are safe

This isn’t an exhaustive list but it should be a good starting point for those anticipating being caught in extreme weather conditions. Before making the essential journeys, check the met office website and the highways agency.Also, see our Ezine article about how to start your car on a cold morning.

Moving on to this month’s driving news, the snow affected the millions of UK drivers although many hit the news as gritting vehicles were slow to respond to key areas. However, one story that made headlines that will cause many to scratch their heads in confusion is the two men who drove their Peugeot down a frozen canal – before plunging through the ice.

Cheating death after the Peugeot car broke through the ice, the two men who were inside the car when it plunged into the freezing water were branded by the police as ‘stupid’, although we suspect stronger words were used down at the station.

The thoughtless duo drove half a mile down the frozen canal before the inevitable happened. Police tracked them down and charged them with reckless conduct. With the emergency services struggling to attend genuine accidents and emergencies at this difficult time, this was clearly a poorly thought out plan and the thrill seekers aged 22 and 24 will find out their fate when they attend Livingston Sherriff Court next month for sentencing.  

Also in the news...
Children’s cartoon Peppa Pig was embroiled in a safety row – because parents raised concerns over the fact that when the cartoon pig was in a car she did not wear a seatbelt.

One parents complained that her daughter had refused to wear a seatbelt because Peppa didn’t. We think that this is ridiculous and blame this on bad parenting rather than Peppa Pig. If I had said this to my mother when I was a child, I would have been punished for being so silly! Cartoon characters are not role models and any parents should be stronger when dealing with a petulant child.

However, to be seen as taking these complaints seriously, the creators of the Bafta Award winning cartoon aimed at children aged two and above admitted that they were “naive” when they began making Peppa Pig. Future episodes of the cartoon will feature Peppa wearing a seatbelt. Another win for the overbearing parents involved it seems.

This is brought to you by Megavaux, supplier of Vauxhall Van Parts

December Driving News

Just like the film Speed, but no terrorists or buses – the story of a man stuck in Cruise Control!

An Australian driver is recovering from shock this week after a terrifying car ride across Melbourne. The driver, Chase Weir (22), was nearing his motorway exit when he realised that the cruise control in his Ford Explorer was not going to disengage, allowing him to slow down for his exit. Instead, Weir had to weave in and out of city traffic, honking his horn and flashing his lights just to get other vehicles out of his path as he helplessly careered down the road at 50mph. For thirty minutes, Weir was convinced he was going to die and covered a distance of 25 miles during his ordeal.

Weir did everything he could to disengage the cruise control, he frantically thumped on the footbrake, pulled on the handbrake and even tried to turn off the engine and remove the ignition key but to no avail.

Quickly running out of options, Weir made a desperate call to the police. With the help of the police, he was able to miss most of the traffic he encountered, narrowly avoiding creating a trail of destruction behind him. The car only came to a stop when he saw he was going to hit a queue of traffic, so the terrified driver put all his weight on the footbrake and pulled on the handbrake, swerving into the other side of the road.
Chase Weir commented,

“I could hear the tyres skidding on the road for what seemed like forever.

“I was convinced that I was going to die.”

Ford issued a statement saying that frozen cruise control was not an issue the company had encountered before, however, if you search Google for cruise control problems, over half a million results pop up. It seems as though Ford may be denying a long established problem. Back in 2005, Ford recalled a number of vehicles due to cruise control related problems.

Some commentators have been dismissive of Weir’s story but we would love to know what you think about cruise control faults you may have encountered.


Funny story of the month:

Two fraudsters who were involved in a ridiculous scam to take driving tests on behalf of dozens of cheats were jailed after admitting conspiracy to defraud.

Ali Abdallah, 28 and Muktar Nuren, 22 are both from Manchester and targeted test centres in Greater Manchester, Lancashire, Merseyside, Yorkshire and East London.

Their own lawyers described their client’s plan as ‘abysmal’ and ‘spectacularly unsophisticated’ as staff at testing centres recognised the two men who were regular visitors and looked nothing like the photographs on the licences they presented.

Police used CCTV footage to link them to the scam.

Some serial impersonators often use false beards, wigs and make up to disguise themselves and repeatedly use the same test centres. 616 cases of impersonation have been reported in the last year.

Failing 33 of the 43 tests they completed, their ‘no pass, no fee’ promise would surely soon leave the hapless duo out of pocket. Those observing the case may be inclined to wonder if the pair should be banned from driving too if they can fail so many driving tests.

When sentencing, Judge Andrew Blake addressed the defendants, telling them, “Luckily, the safeguards that are in place did find you out, but the fraud nevertheless ran for 18 months.”
An investigation has now been launched to locate the drivers who obtained their licences fraudulently through Abdallah and Nuren.

This news has been brought to you by Megavaux. We specialise in Vauxhall van parts and car parts.

How to choose the right van for your needs

The car market may be slow to get back on its feet, but the job market seems to be seeing ‘green shoots of recovery.’ This should mean that soon the car market should be thriving again and the man with a van will become a more common sight.
Regarding choosing the right van if you’re a decision-maker, here is a comprehensive guide to help you choose the best vehicle for your purposes.

What will you use it for?

• City driving
• Long haul (mostly motorways)
• Large loads
• Off-road
• Transporting colleagues

For each of these uses, you would require a different type of van depending on the nature of your business.

City Driving
The Corsavan is perfect for city driving. It’s as small as a normal corsa therefore easy to park in towns where space is somewhat limited. Interestingly enough, it is rather spacious inside so it will comfortably fit two fully grown men in the seats. Exceptionally taller drivers (6ft 4” tall +) may disagree with this statement.

Fuel efficiency is often a problem for city vehicles as constant gear changes and stopping and starting is not great for fuel consumption. If this is an issue, it is helpful to know that car-derived vans such as the Corsavan are well suited to such driving. The clutch and gearbox are likely to wear quickly from lots of gear changes thanks to city driving. It is advisable that drivers be alert to changes in these parts that may signal that they may soon require replacing. Corsavans are not suitable for delivering bulky or heavy vehicles but they’re perfect for moving small loads or for tradesmen working on smaller jobs and typically attracts favourable reviews.

Alternatives include the Daihatsu Hijet or the Piaggo Porter although they are poor alternatives as they are more like small trucks rather than vehicles designed for running around town. Radio stations have chosen Corsavans for their out and about vehicles as they are small, nippy and surprisingly spacious. If you need more space, the Astravan is a larger alternative but not an equivalent due to the vehicle not being small enough to be described as a city car.

Long Haul
In fact, the Astravan is more suitable for long haul journeys than it is going around the city due to the length of the vehicle making it harder to park in crowded city centres but owners of these vans will happily admit that they would choose an Astravan again and again. Not only is it complimented for having a comfortable cab that is on par with the typical domestic vehicle, it handles well and is cost-efficient. The 2009 Astra which the Astravan is based on has fantastic NCAP safety results for an adult which is a big bonus although the pre-2009 models received very respectable ratings. Still, if you are transporting smaller goods across the country, the Astravan is the sensible choice for fuel economy but realistically, a bigger van may be needed for the job. In which case, the next step up is the Vauxhall Vivaro.

Unfortunately, the Vivaro has attracted less glowing reviews compared to the smaller Astravan. Main faults appear to be a weak gearbox and various other complaints relating to bearings on older models.  Yet, the Vivaro has won the top award for ‘Best Medium Van’ seven times since 2001 in the Van Fleet World Awards which is an impressive feat which could indicate that only a vocal minority have experienced real problems. Often hailed as roomy and comfortable, the Vivaro does appear to be a great contender for long drives when you require space. Reviewers report that the engine can be rather noisy but quietens down once fifth gear is selected which suggests that the vehicle is intended for motorway use. However, if you are planning on hiring a vehicle like the Vauxhall Vivaro, please check your driving licence. Drivers who passed their test before January 1997 are entitled to drive this vehicle but drivers who have passed their test since January 1997 need to pass an extra test to add the C1 classification to their licence. The Vivaro and its bigger brother, the Movano both are capable of carrying large loads but very large loads should be left to specialist fleets e.g. HGVs.

Off Road
If you are intending to do a lot of agricultural work or mostly operate in the country, the Vauxhall Frontera is a sensible choice. For those who do not have deep enough pockets to cover the purchase of a Jeep or Land Rover, the Vauxhall Frontera is a sensible and logical choice. Vauxhall have not made the Frontera since 2004, but second hand models are available for good 4X4 entry level vehicle. The cab is set lower than traditional 4X4s which gives it reasonable side protection. Unfortunately, the 2002 model that was tested by Euro NCAP described pedestrian safety as “dire” and that child occupant safety was questionable. Adults fared better but driver safety was impaired with front passenger results being marginally better. 2003 models are often recommended. Similar vehicles for similar money would be up to five years older for the same money but alternatives include the Mitsubishi Shogun and the Ford Maverick.

Transporting Colleagues
If you work with one other colleague, any of the aforementioned vans are suitable for two people, possibly with the exception of the Corsavan for two exceptionally taller occupants. The Vauxhall Movano seats 3 passengers and similar vehicles include the Ford Transit and the Mercedes Sprinter.
Other questions you need to consider

• How much can you afford? Businesses have been known to collapse due to unwise vehicle choices which also include road tax, servicing and insurance.
• How long do you expect to keep it? If you only need a van for a short term, it may be best to consider rental as you will not have to cover the cost of depreciation or servicing etc.
• Will the van be used for towing? In which case the Frontera or the Vivaro/Movano are the better choices but may require extra classifications being added to your driving licence.
• How much time will be spent in the vehicle? If you are intending to drive the vehicle for many hours then comfort should be a big consideration.
• If something goes wrong, do you know where you can take your vehicle for genuine Vauxhall van parts?