This Mercedes A200d with the 2.1 diesel engine came into us for a Diagnostic Code Read because its EML (Engine Management Light) was on.
The Codes were –
P0401 Exhaust gas recirculation (EGR) system – insufficient flow detected
P0638 Throttle actuator control (TAC), bank 1 – range/performance problem
P200A Intake manifold air control actuator, bank 1 – performance problem
After checking some of the live data we decided to remove the EGR pipe to have a look inside the intake system, the system was full of carbon build up which was causing blockages.
After speaking to the customer we found that he only uses the car for short journeys and it very rarely gets a long run.
We are seeing this as a weekly occurrence at the moment, modern diesel engines are not designed for lots of short journeys they are more designed for long distance commuting.
When a modern diesel engine is driven on a long journey it carries out a DPF (Diesel Particulate Filter) regeneration which basically means it cleans out the exhaust system of carbon and soot build up, the same carbon and soot is found in the engine and long journeys help to clean that too.
Once we had cleaned out the intake and EGR system we cleared all stored engine codes and took the Mercedes for a long road test, upon return we carried out another Diagnostic code read and none of the codes had returned and all live data was reading correctly.
The car was given back to its owner and we also advised him to go on at least one long drive per week or the car would be back to us with the same fault.
We have seen quite a lot of Timing Chain faults recently across different manufacturers from Nissan and Renault to Audi and Volkswagen.
The faults range from chains stretching and causing the Engine Management Light (EML) to come on to chains slipping and causing poor running and in some cases non start.
There is a lot of speculation as to why the chains in modern cars don’t seem to last as long as their predecessors such as poor oil quality, poor design, poor materials etc…..
What we can say is this problem is becoming more and more common and it is something you cannot ignore, if your engine starts to get a rattle that was not there before or your EML comes on and you have codes for ‘Incoherence between Cam and Crank Sensors’ make sure to get it into the garage to be checked out before it does any serious damage.
Here we have a picture of the timing chain cover from a 2016 Nissan Pulsar that had recently started to rattle, as you can see the chain was so loose it was starting to catch the top of the chain cover and wear it away.
This Volkswagen Jetta came into us with its engine management light, DPF light and glow plug light illuminated. It had very little power and needed some attention.
Firstly we carried out a diagnostic code read to see what fault codes were causing the light to be on, several codes relating the Diesel Particulate Filter (DPF) being blocked or soot content to high and one relating to boost pressure lower than expected.
Next we tried to clear the codes and restart the car to find out which codes stayed live, in this case all the codes stayed.
We tried to carry out a Diesel Particulate Filter Regeneration which with this particular car has to be done whilst driving.
You have to drive the car in 4th or 5th gear at approximately 2000 rpm until the DPF light goes out, this can take up to 40 minutes depending on how blocked the DPF is.
The regeneration did not work, so back to the workshop for some more tests.
We tested the differential pressure before and after the DPF, this is done using a pressure gauge which is connected on to the pressure sensor pipes, if the pressure is to high the DPF wont allow you to carry out a regeneration and the DPF will need to be cleaned out using chemicals either on or off the car.
The DPF soot content on this Jetta was very high so we decided to remove the DPF and have it chemically cleaned.
Whilst the DPF was off we decided to check in to why we were getting a code for low boost pressure, we checked the turbo actuator pipes for leaks which all seemed ok then we checked to see if the actuator was working using a vacuum tester, the actuator wouldn’t hold vacuum.
We removed the turbo actuator and tested it against a new one (see the video below)
Once the DPF had been cleaned out and we had replaced the faulty turbo actuator it was time to retest the the car.
We cleared the codes and took it for a road test, all the warning light extinguished and we had full power, brilliant.
After speaking to the customer we realised that the car had lost power several months ago and he didn’t have it looked at until now due to the fact of not just one warning light being on but three on the dash.
The car wouldn’t carry out a driven regeneration of the DPF (which they do regularly under normal circumstances) due to the faulty turbo actuator which then caused the DPF soot content to increase until it was full causing all the warning lights to come on.
The Moral of this story is ‘Warning lights are important‘ if you have a warning light come on on your car get it checked out before it causes any more damage.
There are a number of car checks you can perform both around the car and under the bonnet to help keep it in good running order and prevent a breakdown.
Getting your hands dirty under the bonnet might sound like something you should leave to the professionals, but there’s no reason why you can’t maintain some things yourself.
Spending five minutes carrying out these simple checks every few weeks – and certainly before a long journey or an MOT – can save you a lot of time and money in the long run, not to mention help keep you safe on the roads.
To keep things simple, here are 12 simple car checks you can carry out today to keep your car safely on the road and on the right side of the law. We also have a quick video from RAC patrol Matt Woodbridge demonstrating four simple under-the-bonnet checks:
When it comes to preventing a breakdown, remember the acronym FORCES, which stands for Fuel, Oil, Rubber, Coolant, Electrics, Screen wash.
Check you have plenty of fuel in your tank for your journey. It may sound obvious but you’d be surprised just how many people run out of fuel, particularly in harsh winter weather.
Check your oil level is between the minimum and maximum mark on your car’s dipstick and top up if necessary.
If you don’t know which type of oil you need to use, refer to your owner’s handbook or speak to your local dealer.
When it comes to rubber, check both your tyres and wiper blades on a regular basis.
Check your tyres for general wear and tear, splits or bulges, and crucially tread depths (remember to check the inner tread too). Minimum tread level is 1.6mm, although in winter it’s advisable to have 3mm of tyre tread to help with traction and grip.
Also ensure you’ve got the correct pressure in your tyres, checking your owner’s handbook if you don’t know the correct inflation.
Examine your wiper blades and make sure they clear your screen effectively as these won’t last forever and need replacing from time to time due to splits and cracks.
In winter, you can prevent your wiper blades freezing to the windscreen by placing a thin sheet of plastic or cloth, between the wiper blades and the windscreen. Or you can try using de-icer or warm water to free them up before starting your engine.
Check your car’s coolant level. The last thing you need is a frozen engine or for your car to overheat.
Although it’s a sealed system and shouldn’t need to be topped up, you should always double check, especially before a long journey.
Check your coolant levels when the engine is cold and look in your handbook for the location of the filler cap and for the correct coolant and mix to use should you need to top it up.
There are plenty of electrics in your car – from headlights and fog lights to your battery – and they all need to be checked regularly to keep you safe.
Walk around the car and make sure your lights are all working, even the number plate lights, as you can be fined for having a registration that can’t be seen.
You should also check your battery, making sure the terminals are clean and tight (cleaning off any corrosion with hot water and applying petroleum jelly) and that the engine starts correctly.
If your engine struggles to start when you turn the key, get the battery checked out at a garage. If your battery is over four years old it may be getting to the end of its life and could let you down.
When you’re having your battery tested, ask them to check the starting & charging system and whether anything is draining your battery – this will give a better picture of your car’s overall electrical health.
If you are having your battery test ask them to check the charging system and the drain on your battery – this will give a better picture of your car’s overall electrical health.
6. Screen wash
Check your screen wash level in the tank under the bonnet (check your manual for its location), topping up if necessary with a quality screen wash additive or pre-mix, which you can pick up in most petrol stations.
Screen wash is important all year round. In winter snow and grit cause dirty windscreens, while in summer bugs and pollen can easily smear your view – so never put off checking your levels
Make sure you’re prepared for a breakdown and are kept safe at the roadside.
Aside from the vital FORCES checks and if you feel confident enough it’s also worth carrying out a few additional car maintenance checks on other parts of your vehicle to extend its life and avoid a breakdown.
7. Engine air filter
A faulty or clogged-up air filter could reduce your fuel efficiency and lead to reduced engine power, which is why mechanics recommend getting it replaced every 12 months or 12,000 miles, whichever comes first.
If you think your filter needs checking or replacing, simply locate the filter (usually in a black box under the bonnet) and remove it, making note of how it fits before you insert the replacement and fasten the box back shut.
Check your vehicle handbook for instructions.
8. Spark plug (petrol engines only)
More of a replacement than a check, but spark plugs are integral to the running of your engine – one or more faulty plugs will cause an engine misfire so it’s worth knowing how to replace them.
Generally, spark plugs need replacing every 30,000 miles or so and you’ll need the right tools if you want to replace them yourself. Also check your handbook or consult a dealer to check that a DIY replacement is possible.
It’s hard to underestimate the importance of properly-functioning brakes, so keeping them maintained is essential.
Start off by checking the brake fluid level and if low, top it up – check your vehicle handbook for the correct fluid specification Be careful as brake fluid is corrosive, and if you feel unsure then get a professional to take a look at it.
Brake fluid should be changed at certain mileage intervals – again, check your handbook for service details.
10. Air conditioning
Whether it’s 35 degrees outside or barely breaking freezing, it’s essential your aircon unit is fully functioning. However, apart from visual checks of the pipework, there is not a lot for you to check yourself.
Air conditioning system servicing should be carried out by a competent person with the correct equipment. A typical complaint is when the air conditioning does not feel cool enough on hot summer days, this may indicate that the system requires re-gassing – specialist equipment is required and so should be entrusted to an authorised service centre.
No-one wants their car to be known as a “skip-on-wheels”, so keep things clean with a regular interior clean, clearing out your footwells, wiping down your dashboard and keeping only the essentials in your boot.
It’s not just about being a neat freak, a clean interior also keeps you safe on the roads – you don’t want any discarded bottles dangerously rolling underneath your pedals.
Keep the outside of your car clean with a regular wash. If you’re doing it by hand, focus on the headlights, brake lights and number plates as these help you see and be seen on the roads.
Keep all windows clean and clear at all times. As well as being unsafe, an unclean windscreen that limits your view of the road could see you fined for driving a car in a “dangerous condition.”
Should I take my car to a garage?
If you carry out these simple car checks, your car should stay on the road without seeing a mechanic for longer, but if a more serious problem arises you should always seek professional help.
Suspension bushes on all cars go through tremendous stress on a daily basis, some manufactures have got the design right and the bushes can last the life of the car whilst other manufactures just didn’t quite get there!
One of the problems with BMW’s in general is the front suspension bushes. Most of the BMW range suffer with the front suspension arm bushes either failing or being so worn that it causes the car to wander on the road whilst driving and can feel unstable when braking.
Replacing the bushes with either after market bushes or genuine bushes does sort out the problem, but with the condition of the UK roads and the fact that most BMW’s come with low profile run flat tyres the new bushes can be worn out within a couple of years.
The solution on this BMW Z4 was to fit some Power Flex nylon bushes, these bushes are mainly used in Motorsport but can be fitted to road cars.
Watch this video to see just how much movement was in the old worn bushes compared to the new Power Flex nylon bushes.
On the Z4 replacing just the lower suspension arm rear bushes was enough to transform the steering from a loose discouraging feel to a nice tight direct feel that a sports car should have.
For more information on whether Power Flex bushes would suit your car or just for more information give us a call on 01332 205070
A 2014 Citroen Berlingo came in to us with an ABS fault to be looked at.
First thing to do was carry out a diagnostic code read to see why the ABS light was on, the particular code for this Citroen Berlingo van related to an open circuit on the rear left wheel speed sensor.
We checked the actual wheel speed sensor for a fault but it checked out ok, next job was to check the wiring from the sensor back to the ABS pump.
Most of the wiring for the rear ABS sensors is hard to access as it runs inside the van. once we had determined that there was in fact a break in the wiring from the left rear sensor and the ABS pump (by checking continuity of the wires) it was time to start stripping the interior and physically check the wiring for a break.
After removing the passenger seats and lifting the carpets to access the wiring we noticed part of the raised carpet flooring had been trapping the ABS wiring loom between a raiser and the body and over time had rubbed through the wiring and caused it to short out against the body.
We repaired the wiring and and rechecked for continuity through the loom which we now had. Time to clear the stored fault codes and check for a wheel speed signal using the live data on our diagnostic scanner, perfect, the signal was good and the same as the rear right wheel, time to rebuild and road test.
Audi’s little S1 Quattro rocket ship has had a few problems when it comes to its cooling system, this water pump – thermostat housing has had seven re-designs since its original design due to failing water pumps and leaking joints.
To replace the water pump – thermostat housing on the Audi S1 Quattro is a fairly big job, we have to:
Drain the cooling system
Disconnect fuel lines and cooling hoses
Remove inlet manifold stabiliser bars
Remove the complete inlet manifold
Unbolt water pump drive cover
Remove the water pump and housing
Clean all surface faces and hose joints
Rebuild using genuine parts and all new seals
Refill with anti freeze and bleed cooling system
Road test and re-check
The water pump is driven off a small drive belt running from an internal engine shaft and should be replaced along with the water pump – thermostat housing.
Once all the work was carried out and all final tests done the car was handed back to a very happy customer.
This little Citroen DS3 came into us to have a look at due to the engine cooling fan running at full speed.
Firstly we carried out a Diagnostic Code Read on the vehicle, this didn’t help as it had no codes for anything let alone for the cooling fan fault!
Secondly through our Diagnostic Scanner we can operate certain modules on the engine to help us fault find, one of the modules is the high and low speed cooling fans.
When we operated the cooling fans only the high speed fan would work, this gave us a place to start, we removed the cooling fan control module to find that the resistor for the low speed fan had burnt out and required replacing.
When we rang the dealer they had six on the shelf! Always a good sign as common problem parts are always well stocked at dealerships.
Once we had replaced the cooling fan control module (resistor) we carried out another module test using our Diagnostic Scanner and it worked perfectly on low speed and high speed.
After a quick road test to make sure the fans worked with the air conditioning and when the DS3 was up to temperature it was time to hand it back to a very happy customer.
We hope everyone is taking care and doing their best in this strange and worrying time. Trying to fight this Corona Virus is a bigger job than most of us initially thought but we do seem to be getting there and some of those business’s that were affected by Covid19 are starting to re-open.
Aarons Autos will be re-opening its doors as of the 1st June 2020 and once again be offering its excellent ‘Services’ to the general public and local business’s.
We are putting several measures in place to keep our customers and staff safe from the Corona Virus;
We are fitting a Perspex screen across the whole office counter which will have a small cut out for customers to pass keys through and for them to make payments (card payments are preferred but we will accept cash)
We will be enforcing a one customer in reception at a time rule and customers will not be able to wait in the reception area whilst large repairs are being carried out.
All customers vehicles will be wiped down with anti bacterial wipes pre and post work being carried out, technicians will wear gloves whenever possible.
We will be supplying small hand sanitiser bottles for customers and technicians to use after any transactions.
We ask that customers will leave out their ‘Locking Wheel Nut Keys‘ and ‘Service Books‘ where required so we do not have to search around the car trying to find them (reducing contact inside the car).
If you have any other worries or queries please don’t hesitate to contact us.
MOT’s have been extended, but we are urging customers to have their MOT’s carried out as soon as they possibly can (or feel safe enough to do so).
There are several reasons we are suggesting getting your MOT done sooner rather than later;
18 months is a long time for your car to go un-checked, if you had not had your car Serviced just before the ‘Lock Down’ and your MOT was due how do you know if your tyres, brakes or suspension are safe!
Garages are going to be inundated with MOT’s that are actually due on the date you want yours doing (12 month MOT’s) so imagine the difficulty for the garage to deal with double the amount of MOT’s, this is why we suggest contacting us early so we can spread out the work load.
Think of your local Garage. If NO MOT’s are carried out in April or May what will happen next year? Garages will have less work in those months and possibly struggle.
If you would like to book in for the first week of June please contact us by email email@example.com or our Facebook page ‘Aarons Autos Derby Ltd‘ if you would like to contact us after the 1st June just call us as normal between 8.30 – 5.00 and we will be happy to help.