GENERAL

DPF regeneration and oil dilution

Q

A general question prompted by reading the “what van” enquiry from the Dec 2021 Help! section in which you talk of an unsuccessful regen attempt causing excess diesel entering the oil in the sump. Why doesn’t the same situation happen with a successful regen, which I assume has the same amount of extra fuel injected?

Dean Savage

A

The amount of fuel injected during a successful regeneration is as you have assumed correctly the same as if the regeneration fails. The difference is that once the regeneration has been successful the system no longer tries to again regenerate the DPF and so no further excess fuel injection takes place.

It is the continual attempts at regeneration which are the cause of the oil dilution, and if these attempts are not needed, then the problem is negated.

Manufacturers do allow for a small amount of oil dilution during the service cycle of the vehicle and in normal use this would not be an issue.

GENERAL

Degreaser

Q

Can you suggest any powerful but water washable engine degreasers that are in the same league as gunk but don’t have such powerful long lingering smell? I usually end up with a headache and it hangs around for ages, penetrating my skin and clothes as a reminder.

Dean Savage

A

The problem is that engine degreaser does need to be a strong solvent to break down the grease, grime and gunk which accumulates on the engine area. It does also need to be water soluble to enable it to be washed away. There is one option that is easier to use and that is the foam gunk spray which can be sprayed on, then will foam up sticking to the areas which need to be degreased, and is less messy than the brush on alternative. It is of course a little more expensive, but the ease of use does somewhat make up for this.

Another engine cleaner alternative is the Autoglym Engine & Machine Cleaner, this comes out well in tests and is also a water-based formula. There are also a few citrus based cleaners on the market now, but I have not tried these and could not find any reviews to enable me to make a judgement on whether these would be suitable. I should also add that cleaning the engine should be done with great care to ensure that any electronic components do not get affected by the water when washing down the engine –a small amount of stray water can cause a lot of damage on the modern engine.

GENERAL

Tyre pressure monitoring systems

Q

Thanks for the last reply about TPMS systems on our Fiesta. I followed your advice and took the car to a tyre centre – they found that three of the four sensors were duff and needed replacement.

Fair enough the warning light has not returned and the car sailed through its MOT. wheel. That brings me to my letter. I have been looking a TPMS scanning and programming meters from Autel and Foxwell (in the under £200 range). The first one was an Autel TS501 (I have always used Autel code readers and found them absolutely fine). It appears that this will scan and detect all makes of TPMS valve and programme only Autel’s own make of monitor valves.

The Foxwell T100 seems to do pretty much the same thing though is slightly cheaper and comes (on eBay) with a free sensor valve. Both units only programme their own sensors but claim to detect and read any make of sensor.

Given the high cost of replacement TPMS sensors (£80 each is a lot to us tight CM readers) and not exactly trusting some of our motor trade professionals not to rip us off, I thought I would ask your opinion on whether a scanner at the DIY end of the market is worth a punt. Thanks in anticipation.

Arnold Holmes

GENERAL

A

The Autel MaxiTPMS TS501 is for sale on the www.autelstore.co.uk website for £188 and is said to be capable of wirelessly diagnosing TPMS problems as well as activate any known OEM/Universal TPMS sensors, ID clone or reprogram sensors to the vehicle’s ECU, and turn off warning lights. And does go on to say it will only support Autel MX-Sensors. It also comes with lifetime updates. A pack of four sensors on the website costs £94 and individually at this time they are £24.

I found the Foxwell T1000 on eBay for £130 but the T1000 would appear to be an import and the UK version is the NT1001 – at the present time is just under £225.

The batteries in the TPMS