Couple of issues

[BroadSR]

Hi folks,

2014 Leon 5f 184bhp CUPA 167k miles
No DPF and EGR blanked

A few little issues arising which I’m assuming is due to the miles but maybe some of you have had these issues and have resolved them.

Firstly, long time issue since buying the car 3 and a half years ago, is oil consumption. It seems to have gotten worse over time and as it stands it’s burning about 1L per 600-800 miles. Different oils seem to have different performance. I think this may be due to bad maintenance from the previous owners following VW’s mad service intervals but that’s only an assumption, my thinking is either piston rings or valve stem oil seals? I currently change oil every 7k miles.

The car also hard starts sometimes, seems to be more often in warmer weather, however it will always start. After starting if it’s been a particularly long hard start is a lot of white smoke, any ideas what this could be?

Next is coolant loss, this has only started recently, maybe the last 2 months or so. No evidence of leaks or any coolant escaping out of expansion tank, while the engine is cold the coolant is sometimes below min level but after unscrewing cap it fills the tank back up.

Finally, I’ve noticed recently also that when unlocking the car the fuel pump clicks and hums briefly, which I hadn’t noticed before as I’m usually very sensitive to noises that are out of place so I’m convinced I would’ve heard it before.

Hopefully I can get some light shed on this!

Thanks in advance!

 

[BillyCool]

I can make some suggestions but they are only suggestions as I have exactly the same car.

My oil consumption is not great but not as bad as you. I also change oil & filter about every 6,000 miles as well as the usual annual service. I only use VAG 507 grade oil. Current favourite is Total Quartz Ineo Long Life 5w-30 Low Saps Engine Oil

The piston rings are known to seep a little oil over time so it could be that. It seems to be accepted that some of them do it. Could be a minor head gasket issue.

The white smoke after long crank could be unburnt fuel. My car used to long crank but wierdly stopped when I replaced the starter motor, battery and battery earth cable. Not had a long crank in 8 months.

My coolant loss was my heater matrix getting blocked and boiling the coolant during a DPF regen. Could yours be head gasket? Have you have it tested? Has the matrix been replaced?

Are you sure it's the fuel pump clicking? The locking fuel cap servos fail quite reguarly and if it's on the way out they can buzz and click a bit on lock/unlock (very intermittently at times as well). I'm pretty sure the fuel pump only primes when the ignition is switched on.

I can't give you cast iron answers, only things to ponder or maybe eliminate. Mine is on 140,000 miles and apart from the known issues it's been pretty solid and I still enjoy driving it.

Hope you find some answers.

 

[BroadSR]

I can make some suggestions but they are only suggestions as I have exactly the same car.

My oil consumption is not great but not as bad as you. I also change oil & filter about every 6,000 miles as well as the usual annual service. I only use VAG 507 grade oil. Current favourite is Total Quartz Ineo Long Life 5w-30 Low Saps Engine Oil

The piston rings are known to seep a little oil over time so it could be that. It seems to be accepted that some of them do it. Could be a minor head gasket issue.

The white smoke after long crank could be unburnt fuel. My car used to long crank but wierdly stopped when I replaced the starter motor, battery and battery earth cable. Not had a long crank in 8 months.

My coolant loss was my heater matrix getting blocked and boiling the coolant during a DPF regen. Could yours be head gasket? Have you have it tested? Has the matrix been replaced?

Are you sure it's the fuel pump clicking? The locking fuel cap servos fail quite reguarly and if it's on the way out they can buzz and click a bit on lock/unlock (very intermittently at times as well). I'm pretty sure the fuel pump only primes when the ignition is switched on.

I can't give you cast iron answers, only things to ponder or maybe eliminate. Mine is on 140,000 miles and apart from the known issues it's been pretty solid and I still enjoy driving it.

Hope you find some answers.

Thanks for the suggestions Billy, funnily enough I also use the total quartz as it seems to give me the best longevity out of all the oil I’ve used, I don’t mind the long cranking so much as the car always starts but just curious what it could be but I’ll keep what you said in mind there, I’ve got the car booked in to the mechanic next week so he’ll get a look at heater matrix and all that jazz hopefully we’ll find out more, as for the clicking on unlocking it seems to be coming from the general area of the fuel pump, it’s one of those things you forget about until you’re in a panic and hear it when you’re in a rush to get in the car I must have a better look tomorrow (if I remember)

Thanks a mil for your input, I love the car myself also and it’s still got top notch performance despite all the issues it seems to be having, no shame for it I suppose if some of these components have been badly maintained or just never replaced.

 

[BillyCool]

No worries. The car certainly has more issues than my previous Mk1 Leon.

Agree that the Quartz seems to work well with the engine. It's the best that I've used and is not too expensive. Castrol GTX is also very good but also more expensive!

The heater matrix issues are usually highlighted by reduced and inconsistent heat in the cabin. The r/h side usually gets less heat with the temp turned up. Garage can charge up to £500 to change and SEAT quote £1200 as they take the dash out. There is a DIY fix that you can do in 2 hours if you are useful with tools. Matrix is about £80.

The long crank is weird and I have absolutely no idea why mine stopped doing it.

Hope you get some answers!

 

[RUM4MO]

Any/all diesel engines, even direct injection ones, as they are "compression ignition" engines, if the compression is down slightly then they will take longer to start - usually as they regain some compression by virtue of fuel injected into the cylinders. For some this will end up getting aggravated by the lower cranking speed which as you pointed out can be due to an aging starter motor, and/or an aging battery, and/or an earth lead - or supply lead that has now ended up with having a bit extra resistance due to corrosion and/or the crimped terminal at either end becoming slackish.

So, there will be a minimum cranking speed that needs to be achieved before a compression ignition engine will start or start as quickly as expected.