V50 1.6 DRIVe 115 SE Lux

[Holdie]

Hi all

I wonder if anyone on the forum can assist me?

2012 vehicle with just on 118k miles on it. Has been regularly serviced and maintained and generally (apart from a couple of the injectors failing in the last 4 years) has been reliable, and a good motor.

Did a short 20 mile return journey home last week in reasonable weather (there were no issues on the outward leg), probably averaging 50mph on the way. When I parked up at home and turned the engine off I could hear a fairly loud, indistinct ongoing sound in the background. Still in the car, I thought there was a lorry or delivery van parked up nearby with engine running.

When I got out of the vehicle, I realised the noise was coming from the radiator cooling fan which had cut in for some unknown reason. It then ran on for a couple of mins before stopping.

Left it about 30 mins, then went out and re-started engine and let it run for approx a minute, then turned off. Same thing happened.

Mystified as there had been no warning lights on the journey back, the engine temp gauge was normal with the needle at approx the halfway mark on the dial, and the vehicle had been running normally.

I'm not mechanically minded, but took a look under the bonnet. Coolant level was where it should be, and no sign of any leaking fluids underneath the car on the roadway.

What I did notice however, at the front LHS of the engine bay, to the left of the plastic engine cover, was a smallish circular 'thing'(!) - possibly a thermostat?? - and in the centre of the top of that, there was what looked like a small leakage of some sort of fluid, which was bubbling very slightly in the same way as a bike inner tube might do when locating a puncture.

Any ideas / thoughts / diagnosis?

The only thing that has occurred recently prior to this is that I bought 2 new injectors and had those fitted, on the basis that the other 2 had gone in successive years and it made sense to pre-empt any further problems. These were new, reconditioned, Lucas items and were fitted by a local Bosch garage.

Since then, although once warmed up the car has been running normally and returning a good mpg, the start ups have been getting progressively worse, the engine sounding clattering, and for the first few mins of every drive the car kangarooing and feeling like it might stall. Also it sounds and smells like an old diesel taxi, and is throwing out old style black exhaust fumes when I accelerate, none of which it did before.

I have a suspicion that the garage merely fitted the last 2 injectors, but failed to recode them or take the car for the required recalibration drive to confirm all was working properly, but I have no proof of this. The invoice gives no clue whether this work was done or not, but I (perhaps stupidly?) thought this would be a given and didn't specify this to be done when I booked the car in for the work. Suffice to say, it's not a garage I'll be using in the future, and it was my intention to book it in elsewhere to get this checked out when the fan overrun issue arose.

I just find it strange because when I've done long journeys during the heat of summer months I can only remember the fan ever cutting in on a couple of occasions, and I think one of those was when stuck in a motorway jam.

Anyway, if anyone out there who is mechanically adept can assist, I'd be really grateful for your input.

Thanks

[sunstriker]

I assume this is a diesel vehicle. The fan running may indicate you are interrupting a DPF regen cycle. Do you drive short distances? If you get black smoke I reckon the DPF has failed. Probably caused by bad injectors generating too much soot. Just a theory of course...

[Holdie]

Hi. Thanks for your thoughts on this.

Yes, diesel engine, and unfortunately mainly short distances, so what you say about the DPF may well be the case.

I have to say the weather was so crap on that last journey back when I first became aware the fan had cut in, that I wasn't really aware of anything else going on at the time while I was driving - ie. DPF regeneration cycle - certainly there was no obvious indication that was going on. Should there have been, or is it just silently in the background?

I had to scrap a previously good vehicle due to DPF problems - that was a Vauxhall Zafira Sri - so not feeling great about possible repeat problems with the V50. Presumably replacement DPF fix is £expensive.

I may risk trying the volvo on a 30 min each way journey I need to do later this week, and perhaps drive in 4th gear rather than 6th to keep the revs up

[Kev0607]

The bubbling you describe sounds like a thermostat leak, or the hose going to the thermostat. It doesn't sound like the car is overheating, as the temp guage is reading steady, but the thermostat definitely shouldn't be bubbling. That may be a reason as to why the fan is staying on, or it could be a faulty relay/fuse?

I'd be tempted to bring the car to another garage and describe the symptoms you're having like rough running, black smoke etc etc and fan running more than normal. It would also be helpful if you took a video of the bubbling around the thermostat and show it to the mechanic... that may help them out (assuming you can replicate the issue).

Diesel cars and lots of short journeys doesn't work too well. Being honest, its asking for trouble really... They need regular motorway trips to clear the soot. If you're only doing around town mileage, petrol is a better option for that. However, a motorway drive won't do it any harm. Do that and see does the black smoke improve. Dropping it down a gear or two is a good idea as you mention. Keep the revs high and make sure you stay above 60mph for at least 40 minutes or even longer if you can (20 mins each way minimum).

Generally, DPF regeneration is just something the car does in the background so to speak. If you pay real close attention, the engine can sometimes sound different. When this occurs, its not uncommon to smell fumes.

Its entirely possible the car is trying to do a DPF regen, but I think you've got more than one problem. It shouldn't be running rough after new injectors, nor should the fan really be running too much, not in this weather anyway.