Melett: More car and van turbochargers
Published: 04 November, 2020
Melett has introduced three new turbocharger units suitable for a variety of vans and cars. The first turbocharger fits the 2.2 diesel engines found in Citroen Relay, Fiat Ducato and Peugeot Boxer vans. The second unit is suitable for a range of Renault 1.5 diesel models including the Captur, Clio and Kangoo; Dacia Logan and Sandero models; the Mercedes Citan 108D; and the Nissan NV200. The third model is another van turbocharger, developed for the Volkswagen Crafter 2.5D.
www.melett.com
- Lemförder switchable engine mounts
Under its Lemförder brand, ZF Aftermarket has introduced a range of switchable engine mounts for a number of Audi and Mercedes Benz models. Using an integrated air spring this can actuate two different characteristic curves depending on vehicle and rotational speed. The mounts are currently available for Audi and Mercedes-Benz vehicle models and includes the Audi A4, A5, A6, Q5, Q7 and Mercedes C and E Class, GLK, GLC. ZF Aftermarket recommends that all engine mounts always be replaced during repairs, not just the defective part. Otherwise, there is a risk that the new component will have to absorb higher forces and vibrations because the remaining mounts are already heavily worn which may accelerate subsequent damage.
www.zf.com
- Petrol and diesel ban by 2030?
The government is poised to accelerate the ban on the sale of new petrol and diesel vehicles, it has been reported, with the Prime Minister expected to officially move the deadline to 2030 later this week.
- Dayco: NTR kits
Dayco has introduced a number of timing belt kits. KTB917K caters for several Ford and PSA applications, as does KTB967K. Meanwhile, KTB1047 provides coverage for Nissan’s Almera (1995-2000) and Primera (1996-2002).There are also three water pump kits. KTBWP9140K covers the 1.6-litre diesel Ford Focus (2004-2011) and Mini (2006-2010). KTBWP9170K is aimed at Vauxhall’s Crossland and Grandland 1.6-litre diesels (2017-). Meanwhile, KTBWP9670K has been brought out to cover 2.0-litre diesel PSA applications including the 308 (2007-2015), C4 Picasso (2006-2013) and DS5 (2015-18). Another addition is 7PK1457K, a seven ribbed poly-v belt, for the 1.6-litre Honda Civic (2012-2015) and CR-V (2015-2018)
- Government to ban petrol and diesel cars by 2030?
The sale of new petrol and diesel cars could be coming even sooner than expected, with the government looking to end the sale of internal combustion engine vehicles as early as 2030, 10 years earlier than the previously announced 2040 deadline.
- Diesel diagnostics for the workshop
I’m mindful of several recent diagnostic topics that focused on cutting edge opportunities such as noise and vibration analysis. It also reminded me of the most important aspects of fault finding; to focus on the symptoms, ask relevant questions and conduct a methodical approach based on systems knowledge, accurate data and a proven process.
All of this really boils down to training, experience, and confidence. There are no short cuts, cheap fixes or internet gurus. There are however basic steps that are easily introduced into your workshop procedures.
This brings me to the topic in hand. Can we conduct relativity simple tests on common rail diesel systems? Not only can we, but we must! Remember, the foundation rule of fault finding is a simple methodical approach. Don’t expect a magical fix-all in less than 1,000 words. However, I can provide a pathway that will illustrate the area of responsibility and potential investment in time and money.
Vital information
The first vital step is to listen and ask questions. Owners often have vital information. Remember this is not a recipe for short cuts or silver bullets for your machine gun. Your approach will always depend on the extent of problems. Will it run? are there any mechanical noises? Is there a loss of power? if so when? Is the fault intermittent and how did it start? There is an endless list of questions that will help establish a hidden history.
I often find that a physical examination or health check helps understand the way the vehicle has been driven and serviced. This will often expose basic problems especially with charge pressure circuits.
Try to explore all non-intrusive tests first. They may not be entirely logical in order of priority, but do provide results in the minimum time period. With experience, you will hone these steps into a razor-sharp intuitive process.
Serial investigation
Serial investigation is without doubt the correct first step. Do not jump to premature conclusions as serial data often shows symptoms, not cause. For example, a faulty air mass meter will cause EGR calculation error values, incorrect load and boost calculation. This is a common problem with many causes.
The volumetric efficiency relies on the intake system, swirl flap control, turbo spooling, and a free-flowing exhaust system. Please note that I keep my thoughts non-specific yet focused on all possible causes. This is a very important reaction in any diagnostic process.
Assuming a non-run condition, excluding any serial clues as often there are none, I would always check for the correct rail pressure. This can be done with a DMM. Expect around 1-1.5v with a quick rise time of 0.5-1sec. If it is slow to rise or low, check the priming system including the filter. This should be done with a gauge. Remember pressure, flow and pump current. This will depend on system type so check the schematics carefully. Most systems now prime at 5-6bar.
Isolate components
A slow rise time may be due to an internal leak or worn components within the high-pressure system. This includes the HP pump, rail limit valves, and injectors, as well as volume and pressure regulation devices. Always isolate various components and conduct a blind or proof test before suspecting the pump. They rarely fail, unless run dry or have contaminated fuel.
The PCM requires camshaft position data to sync the injectors and crank position once running. If recent belt replacement or engine repairs have been carried out, add this to your list. To check the injector sync against cam and crank position is a bit technical. To perform you will require a scope and current clamp.
Quite often the serial data identifies the incorrect timing sensor for position error. This is due to the PCM looking at the camshaft first. Slow rotation speed may be due to a faulty or incorrect battery, so check charge and health status with a suitable conductance tester. Yuasa have a fantastic free online training academy.
Next check relative compression. This is a simple cylinder balance check but when compared with current and rotation calculation will accurately predict correct compression.
Identify
A blocked exhaust or failed open EGR will prevent the correct combustion properties. Exhaust back pressure can easily be proven from the map and DPF pressure sensors. Plotting them with a scope will quickly identify intake or exhaust restrictions. The maximum DPF sensor value cranking or at idle should be 0.5-1.25 volts, 100mbar-1.5psi.
Injector type, solenoid or piezo faults will normally be identified within serial data. A single faulty injector circuit will normally shut down all fuel delivery. It is also worth noting that if a minimum rail pressure is not reached, the injectors will not be activated.
So back to priming. Leaks, faulty rail sensors will all contribute to a non-start.
If you are looking for more information, visit www.ads-global.co.uk for courses and dates, and Autoinform events.
