Short Journeys - Bad?

[irc]

Not usually an issue for me as I get onto the motorway a couple of times a week at least and give the car a good run going to work.
As I'm off work just now the car is sitting and just getting used for short runs. One or two miles each way.

Random question that occurred to me. Is it better to forget about it as my normal use pattern has plenty long trips in the mix? A few weeks of short trips won't matter?

Or, once I decide I'm using the car do a few more miles to get the oil temp up to over 80C before going home?

I'm reminded of a neighbour who worked at the local school and used her car to drive there and back each day. 0.4 miles each way. And less if she walked as the footpath is more direct.

I appreciate this a trivial matter but if you can't ask it on Pistonheads where can you?

[Cloudy147]

I wouldn’t have thought a few weeks of it will make a difference, if long journeys are to be resumed soon.

I think diesels tend to be the most unhappy about prolonged short journey life, but for a few weeks I can’t imagine even the most delicate of engines is going to grumble.

[Sebring440]

You haven't told us if your car is petrol or diesel.

If it's diesel then short journeys are a big no-no, and with a petrol car it's advisable to (at least) get it up to normal running temperature.

[Lester H]

No provided 1) a decent e.g. 50 mile weekly run on main roads 2) oil changed regularly with fully synthetic at least every 10k miles.

[Panamax]

I'm not aware of any indication that modern petrol cars suffer from frequent short journeys - millions of cars must be used that way.

The thing to watch out for is keeping up with regular oil changes. There are a number of reasons for this which include,

• Petrol in the oil - caused by fuel getting past a cold engine's piston rings while it's running rich at a cold start. With modern fuel injection this is nothing like a s big a concern as when people would pull out a manual choke for further and/or longer than necessary.
• Water in the oil - caused by condensation inside an engine that never gets hot enough for long enough to evaporate it off.
• Crud in the oil - typically soot and other stuff which occurs mainly from cold starts and is able to blow past the piston rings.

An occasional long run that gets the engine right up to temperature for an extended period will reduce the issue. The excess fuel and/or water in the oil will evaporate off and get burnt through the engine via the "positive crank-case ventilation" system.

[Smint]

Short journeys come under harsh use, so assume harsh use when judging when to service your car with new oils and filters.

[fido]

As above. Anything that isn’t the optimum usage i.e. incorrect warming up to short journeys will degrade the oil more than average so just change the oil more than average. An Italian tune-up every so often makes sense.

Edited by fido on Saturday 25th June 15:19

[irc]

Thanks for replies. 1.4 petrol Superb. On annual oil changes and doing 10k miles per year.

[A500leroy]

Itll be fine, take it for a long trip once a month, change the oil at 6 months ( oil change is cheaper than a new car) and keep an eye on the levels evey week, Also clean the underside of the oil filler cap if any mayo turns up, it will just be condensation from the short runs normally over winter.

[swisstoni]

No problem at all imho.

Perhaps if someone did an autopsy on the car whenever it comes to be scrapped they may find that it had a trivial amount of extra ring wear (or whatever) but that it eventually succumbed to failing it’s MOT on brakes or corrosion which the final owner didn’t want to fork out for.

[shtu]

irc said:

Is it better to forget about it as my normal use pattern has plenty long trips in the mix? A few weeks of short trips won't matter?

Correct, don't even think about it.