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.
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