Old VW antics

[littlepolo]

Just before the xmas holiday I replaced the n/s side light with a long life bulb. It has failed and needs investigation.

[littlepolo]

48mpg recorded on the previous tankful. 70/30 highway/urban. Surprising in consideration of the low temps we have been experiencing.

[littlepolo]

During recent very wet weather on starting from cold DTC 17584 appeared. The reader also showed 18049 which has been indicated for some time, I guess, since the A/C has no pressure. I had noticed earlier that during very wet weather the engine is a bit rough when starting from cold, with a slight misfire and what seems like hunting. One of the ignition coils has a slightly damaged connector and I intended to swap that out. I'll reset the code and see how it goes.

[littlepolo]

I've reset the DTCs and the engine check light has not yet returned. I suppose I should scan to see if the code has returned. Otherwise, I noticed that fuel consumption had increased. I'm hoping that will return to the very good 44-48mpg I'm achieving.

[littlepolo]

Thankfully, DTC 17584 has not returned. I calculated the mpg at 36.5 (urban 100%) and would have expected at least 40 and nearer 44 if all was well. I've driven the Polo for over 100,000 miles now and notice how the fuel gauge moves. I put the battery on a smart charge and noticed it was down on voltage. I'm wondering if that might have contributed to the DTC occurring along with the very damp weather. With the battery charged, and the DTC cleared, the Polo runs much smoother. I feel it's back on track with mpg. I'll swap out the ignition coil with the dodgy connector for a good one when the fine weather arrives. Another job coming up is cambelt/waterpump/coolant. I have an INA cambelt kit and Febi waterpump at hand.

[littlepolo]

Back at 45mpg with no DTCs other than the A/C. I added a top up can to the A/C with a leak detector but could not see any indications of a leak. The pressure has dropped again so no A/C. Not sure if it's worth a proper regas - it might last a while longer though before losing pressure.

I fitted a new Varta battery after the previous Bosch AGM battery failed after winter (it didn't last long)

[RUM4MO]

Bosch AGM failed early, not good, I still have the new Bosch AGM that I bought for my wife's 2015 Polo - just before Brexit hit us, just in case supplies became trickier and more costly - that was a complete double or treble fail as battery supplies continued as before, prices did not rise much - and that 2015 Polo's factory fitted Exide EFB (Stop/Start) is still looking okay!

AC - yes, a new Nissens condenser and all required seals is still resting in the attic - and that car still only lasts 6 weeks after a re-charge, I really really should get it looked at by a proper mobile car AC person, I still think that it will end up being the evaporator - and that will be annoying to replace. To compound my errors, I bought a used main fridge pipe from a breaker - but somehow managed to convince myself that it was the HP side pipe that I needed, when I had previously worked out that it was the LP or suction side pipe that might be leaking under certain conditions - oh bother, just something else to store in the airing cupboard!

[littlepolo]

I read somewhere that Bosch and Varta batteries are made in the same factory, though I don't know if that is true or pertains to a particular location.

I replaced an old Varta that appeared to have failed in my other vehicle last year and eventually was able to get some life out it after putting it on a repair charge with an electronically controlled charger. I keep it as a backup.

I have a UV torch somewhere so will have another check around the A/C lines for leak indications before the fine weather and light evenings arrive.

As for mpg, I achieved 40mpg on purely local driving (short runs) moving stuff during the recent cold spell. I've just recorded 48.25mpg after some long runs so it seems the fuel trims have sorted things out after the replacement battery/ECU reset.

On checking the oil at the weekend (still using Mannol 0W40) I noticed that the coolant level in the expansion tank was low with some indications of leakage below. I traced this to the return pipe. I tired resetting the clamp, hoping it would pinch up a bit more but no luck. I was reluctant to remove the pipe to check for a crack in the pipe fitting so I pushed the hose on further and fitted a jubilee clip after the clamp and right up against the tank. This seems to have stemmed the leak for now.

With the Polo coming up to 22 years old this Sept I'm wondering if the return hose has simply aged and broken down. There is no movement of the fitting to suggest that the pipe fitting on the tank has cracked but I guess there could be a fracture. A replacement expansion tank (Febi) is around £13 and the hose £30.

The cam belt assy and water pump is due a change on mileage and is a bit over on time. I can see no concerns with the condition of the belts but will probably get on with the work as soon as the weather permits. I will do an inspection of all coolant hoses at the time and replace anything remotely suspect as I don't want to have to do unplanned work.

The other main task over summer is to clean up the rear crossbeam and apply anti-rust treatment as the plastic(?) coating is coming away.

The drivers door sticks so I plan to have a look at that too.

[littlepolo]

49.52mpg recorded on 260 mile round trip at highway speeds. A shame it didn't get to 50!

On setting out in the car after it has been sitting in the sun at 16C the rear fog lamp illuminates with the side lamps. After driving a short distance, the fog lamp extinguishes.

[littlepolo]

On a recent 174 mile round trip I recorded 59.9mpg. Highway driving at 60-ish mph. On the exact same trip at 65-ish mpg I recorded 53.5mpg. Both journey's were free of obstruction and the former journey I stopped over at a service station for an hour before turning round whereas the latter journey I did not. Weather/road conditions were similar and aside from the cruising speed variance the only other factor is that on the second trip I did not top off the fuel with the ethanol booster (a 10% difference with the treatment sounds a bit high). I double checked the figures. Best ever mpg.

[littlepolo]

At a modest 18C ambient the front window controls crossed over briefly such that the right hand button on the driver's controls lowered the passenger window and vice versa. An hour or two later all returned to normal.

[littlepolo]

The radiator expansion tank had been dropping in level since quite some time ago. I had a casual look over summer and found it was leaking from somewhere nearby the return hose. I could not see the leak and put an extra clip on the return hose. As it was only losing a little (less than a cupful) I topped up and put a thorough investigation off. On a recent drive the low-coolant alarm triggered and I had to add more water (a bit over 0.5l, maybe 0.7 or 0,8l). Anyway, I had a close look and found a split in the return union on the expansion tank, up close to the tank body. It seems to have a kink in it near the split so I'm wondering if some ham-fisted person might have done it at some time. Anyway, I ordered a replacement and fitted it and hopefully all will be well.

[littlepolo]

I had intended to do some long runs late summer to check on mpg and try to achieve a 'best ever'. It was the beginning of September before I found time and the necessity to travel a distance and clocked up 392 miles before the low-fuel lamp illuminated. Unfortunately, only ~70% of those miles were highway and the rest local running. Anyway, I calculated an average of 47mpg over the distance. The refill in September was 38 litres, implying 7 litres in reserve and another potential 70 miles range. Overall, that's not a bad range from a 45 litre tank on an old 2002 1.4 auto.

If I recall correctly, the best mpg last year was over 50mpg and I was hoping to achieve 55mpg. At that miserly consumption, the range would be around 450 miles until the low-fuel lamp illuminated, with another potential 80 miles range on reserve. With the mpg now being quite predictable, that will be my target for the summer ahead (obviously not running down to the vapours - I changed the fuel filter a few years ago and don't want to do it again).

During the recent cold spell, I noticed the fuel gauge going down faster than usual and calculated 37mpg (the lowest in several years) after multiple cold starts and only short runs. After that, I was encouraged by the slow fall of the needle during more regular driving over the past few weeks and curious when the low-fuel lamp illuminated at 391.2 miles. The refill in February was 40.6 litres and the overall mpg calculated at 44mpg.

I was curious about the volumetric difference and did some investigation. It seems that approx 0.9 litres difference can be accounted for by seasonal differences in ambient temperature (volume expansion/contraction), with the remainder being accounted for by seasonal fuel blends, and other performance factors such as cold tyres, increased idling, use of the heater and general road conditions.

[littlepolo]

The new radiator expansion tank seems to have fixed the slow leak. The old Polo is now back to a consistent 47mpg following milder weather. One slight annoyance that has occurred is that the sealtbelt warning lamp on occasion flickers (sometimes after switching off the ignition). I have a cam belt and water pump kit ready to fit when the weather is warmer. The two other jobs planned for this year are to replace the original back box due to a slight leak after 22 years and paint the rear crossmember where plastic is peeling off before corrosion occurs.

[littlepolo]

50.1mpg recorded over 220 miles (70/30 highway/local) without even trying. Aiming to achieve 55mpg over a long run this summer.