Help!
GENERAL
E10 fuel
Q I am sure this is a question that many will start asking with the introduction of E10 fuel. Could you help me with the aid of your sources identify if my wife’s beloved 1997 Clio Mk1 ph3 is OK to run on E10 fuel?
She has owned this Clio since nearly new, and as you can see from the photo, my friend didn’t just tidy-up the peeling clear coat on the bonnet but transformed it. As such she does not want to get rid of it!
The Clio was 1st registered in April 1997, which is where my uncertainty lies. I have checked the.gov website that says from 1997 it should be OK, listing a few 2.0 engines that would not be able to use it. The ACEA website helps a bit by stating that vehicles manufactured after 1st of Jan 1997 will be OK. As the Clio was registered in April 1997, it may be that it was made in 1996? Can I make the assumption that to be sold as new after the 1st of Jan 1997 it must comply with the incoming rules, or is it the type of seals used in fuel systems then were acceptable? I have been unable to contact Renault.
What is your opinion? I am tempted to use super unleaded. The only information regarding fuel I can find in the manual is it should be 95 Ron or better.
Dave Fox
A As part of the government’s targets to reduce the use of fossil fuels and the resulting emissions, is a reason behind introducing E10 petrol. The E10 replaces the E5 now in use and means that the percentage of ethanol in the fuel increases from 5% to 10%. This small increase will make little difference to later vehicles which have been designed to run on the lower carbon fuel, but could be detrimental to some engines.
Vehicle compatibility can, as you have found, be checked on the gov.uk website. According to the government website E10 petrol is cleared for use in all Renault petrol vehicles marketed since 1st January 1997, except for the following models:
Megane 1 with 2.0-litre F5R direct-injection petrol engine (1999-2003)
Laguna 2 with 2.0-litre F5R direct-injection petrol engine (2001-2003)
Laguna 2 with 2.0-litre F4R Turbo engine (2000-2002)
Espace 4 with 2.0-litre F4R Turbo engine (2000-2002)
Vel Satis with 2.0-litre F4R Turbo engine (2000-2002)
Avantime with 2.0-litre F4R Turbo engine (2000-2002)
As you mention this is slightly unclear and does not specifically confirm that your wife’s Clio will be compatible.
Your wife’s Clio was registered in April 1997 and is fitted with the D7F engine which was designed with the newer emissions regulations in mind and so is compatible with the new grade fuel, but as the new E10 fuel does have a slightly lower efficiency and will give a reduced mpg output, you may wish to use the premium fuel as the extra cost will be offset by the better mpg figure.
It is not just running issues that need to be considered with E10 fuel though as ethanol used in the E10 is hygroscopic, meaning it absorbs moisture from the air. This, in vented tank systems, can allow the moisture content in the fuel to increase and allow a greater problem with corrosion in unsealed fuel systems. As your wife’s Clio does have a sealed system and uses an EVAP valve to vent the tank, this should not be a problem.
I would swap between the E10 and the premium fuel at every other refill as this will give a balance between the higher grade and the higher ethanol fuel.
GENERAL
Oil spec
Q Further to the letter from Darius (December 2020 issue), I have been using Costco’s keenly priced 20 litre containers of Chevron Supreme synthetic motor oil (SAE 5W-30, ACEA A5/B5, API SL/CF) for many years in older petrol cars, in compliance with the manual specified grade and without apparent problem.
The limited shelf life of oil is, or should be, well-known, but with two or more cars in the household needing annual oil changes, it should not be necessary to keep an opened container for much longer than a year. On one occasion when I had some oil near the end of its shelf life, I used it as a flush, before doing the oil change with the new supply. The empty container provides a convenient-sized receptacle to minimise trips to the council tip for disposal of old oil.
A downside is the necessity of decanting, the small size containers can often be poured directly, avoiding the potential for introducing contamination through the use of jugs and funnels.
I am old enough to remember a time when oil choice was very simple, but things have changed and when I get around to replacing my old cars I will have to be careful in choosing what to use. The potential cost saving on oil is trivial by comparison with the potential cost of getting it wrong. Not so long ago Haynes manuals, and also the carmaker’s glovebox handbooks, specified oil required in terms of ACEA and API grades. Now they only list the carmaker’s oil specs.
Question – is there any easy way of equating one to the other? Internet search does not provide this information, failing which, it might be safer to stick with the carmaker’s branded oil. Internet search does, however, suggest that the ‘C’ in ACEA C grade stands for ‘Catalyst Compatible’.
I believe that the C grades only came into being in 2004, long after cats became mandatory. I do not have, or intend to acquire, any diesel cars but might well acquire a GPF-equipped car and had thought that the low SAPS C grades were only essential for DPF or GPF cars. Would it be beneficial to use them for all catalyst equipped cars? SAPS, though bad for particulate filters, are good for lubricity. Are the alternative additive chemicals more expensive and/or of poorer performance?
Martin Keating
A The cost of oil when bought in larger quantities can be reduced and if you do have more than one vehicle which requires the same specification this can be an advantage.
The oil classification and grades have become increasingly more complex over time and the classifications set by the manufactures are difficult to cross to the ACEA specification. Whilst a manufacturers grade specifications may be up to a certain ACEA grade, it does not indicate that the ACEA grade will be up to the manufacturers specification.
As an example, the Mercedes oil grade MB229.5 is an oil which conforms to ACEA A3/B4 but not all A3/B4 oils will conform to the MB229.5 specification.
It is possible that a GPF (Gasoline Particulate Filter) will become more common on petrol vehicles as we move towards the higher emissions standards and with this in mind the C grade oil will be needed. At the present time many vehicles are still in the ACEA A-B oil grade bracket.
One of the problems with the demands on modern oils is that some engines demand high HTHS (high temperature high shear) viscosity whilst others require a lower HTHS viscosity in order to maintain a better fuel economy.
The basic oils are mixed with an additive pack and these packs determine the
