MikeT's C5r 1.6 hdi Estate

[lexi]

That is a load of interesting data on the 1.6 hdi Mike. In cold winters like we had there, all diesel cars mpg is well down. You are getting a good bit more on mpg than my Donk does. You are the official 1.6hdi C5 Guru now!

[MikeT]

That is a load of interesting data on the 1.6 hdi Mike. In cold winters like we had there, all diesel cars mpg is well down. You are getting a good bit more on mpg than my Donk does. You are the official 1.6hdi C5 Guru now!

"1.6hdi C5 guru" thanks but
Not by a long chalk. Many more 1.6hdi "smarts" on this forum than me. I might try monitoring live air and fuel data if I knew what I was looking for.

I know winterised fuel may be a factor as is the cold weather and shorter days etc but as mentioned, previous winters haven't shown such a marked drop than it did this year. I used to be able to tell when a leaky front tire needed re-pressurising as I'd start losing tenths of an mpg, so seeing a loss of 20% or more has me concerned.

[MikeT]

I don't know what to think now. From a cold start this afternoon and trip to the shops followed by a visit to the Forest, it reports the lastest average as...

[GiveMeABreak]

But it always starts higher when reset and soon drops like a lead balloon after a few trips - either that or there was a strong wind behind you. Wait for another 50 to 100 miles and that will bottom out to the 50s I suspect - but in either case - much more than my miserly 42.8 - in hilly Wales.

[MikeT]

LED replaced and working without causing a BSI upset removing the battery, even though I use an abbreviated procedure to that commonly quoted.
No idea where the LED half of the old sidelight went, though.

I give up, I'm going back to Halogens!
NS sidelight out again tonight.
Battery removal procedure... removed holder to find yet again the LED portion of the bulb has parted company. This one is almost definitely still in the lamp and will have to be retrieved. It too isn't magentic so will have to try other retrieval methods....

[MikeT]

But it always starts higher when reset and soon drops like a lead balloon after a few trips - either that or there was a strong wind behind you. Wait for another 50 to 100 miles and that will bottom out to the 50s I suspect - but in either case - much more than my miserly 42.8 - in hilly Wales.

Nooo, it's the opposite with mine, Marc. After a splash n dash, the short drive home (engine fully warmed up) would always show low 50's then slowly improve to at least mid-50's.
Lately, it's plummeted to low 40's after a refill as happened yesterday. However, this time the recovery (from overnight cold) happened sooner and exceeded my expectations by a good margin!

[GiveMeABreak]

I reckon those sidelights are playing silly bu**ers with your electrics! Mine always starts off in the 60s and 70s after a full up and reset, with feather on the pedal and 30 mph. First hill and dropping rapidly and after 25 miles back to 46, then after a few days back to 42 ish and that’s it

[MikeT]

How strange I'd completely forgotten - during the heavy rains a while back I drove through a "puddle" on the nearside and was rewarded with an almighty bang through the car from the hidden pothole it masked - I only recalled it last night (probably de-sensitised due to the prolification of them nowadays) and wonder if it played a part in the sidelight failure.

Mum's taxi today - off to Tesco first (where Citroen was showcasing new C3 and C4 Aircross), then picked up a "perch" chair she wanted to buy - all town driving. The mpg is still showing 61.3mpg! Usually it'll drop initially on warm-up and can be coaxed to recover that loss.

[MikeT]

I give up, I'm going back to Halogens!

I may have spoken too soon.

Looked up the part on Citroen Service and it listed two items

1616431880 - MQ Bulb £4.43
0000621694 - E-Bulb £13.79

Local Dealer says first number doesn't exist on his system.
He brought out the right bulbs in a Citroen-branded box but said they were the more expensive part number.
I walked away in disbelief.

[MikeT]

Found the original LED head that broke off inside the diffuser and retrieved it using a flexi grab tool. It is possible it was impinging on the LED that replaced it and caused the second to break off at the slightest road bump.
Inspecting it confirms the two parts were indeed just held together with two solder joints. I am confident if it had been properly glued, it wouldn't have broken.

Considering the expense of quaility halogens, I might as well spend the money on a pair of expensive philips LED's and trust they are of sounder construction!

Meanwhile, the mpg has not only held at over 60 for the last 150miles, it's actually improving! I wonder if a lump of EGR goo broke off and caused a temporary restriction until being eaten by the engine? It's quite bizzare to have it go from high 40's to low 60's.

[RichardW]

Don't know what LEDs you are using, Mike, but we have had H6W LEDs in our C4 for about 4 years - no problems (well except that on the OS one the resistor has failed so it comes on dimly when the BSI is waking up or shutting down!). They were only cheapish ones from e-bay AFAIK!

[MikeT]

I'm blaming cheap led's until I know better. The last pair were made of rice paper, I swear!
However, initial suggestions it could be electrical, I won't be investing (£26+) in the reputable OE halogens at this point so the next set of LED's I've ordered will have any observed weakpoints reinforced before fitting.

[GiveMeABreak]

Many of the bayonet designed ones have obvious weaknesses - trying to fit a square peg in a round hole type situation and can easily come away at the slightest pressure. I don't know whatever possessed car manufacturers to even consider H6W bulbs - they are totally useless. At £18 for a set of 2 Philips branded ones - dream on - the reviews show 57% with a one star rating on Amazon, so not very popular.

I have these on my X7 reversing lights Mike - I just remembered and although they are ok - have not failed at all, the light output is still abysmal, but better than the OEMs as you can see by the LEDs at the bottom. A bat could see more in reverse than with the output from these things, so practically useless - but they are more aesthetically pleasing IMO.

[MikeT]

Things would be so much simpler if they were more visible/accessible. I can't tell if I've inserted the holder correctly. There's one pair of slots in the recess (9 and 3 oclock) but two pair of lugs/fins that can be aligned into them. Both ways "seem" to fit and hold but out of sight it's impossible to deterime which is correct.

[GiveMeABreak]

They should only go one way - they have offset pins as you have stated - you should be able to 'feel' if they are not right. I can't recall now on my MK II (it has the Xenons, but I'm sure that the wires with the holders came out of the socket, so you could fit the bulb then fit the wire and socket back into the housing. If I'm remembering correctly it should be easier to see if the fitting is right or not.