john.errington

My 2009 Octy 2 Tdi (BXE engine) has done 150k miles. It had its EGR mapped out two years ago, after a HOST of problems - and it's run fine ever since. After the remap some whine from the turbo became very noticeable, and I think it's been getting worse recently. When I turn the engine off I can clearly hear it spool down. However, there is NO smoke form the exhaust, It's not using oil, no fault codes .. It makes me feel anxious because I dont want to be stranded with the turbo failing and costing me a fortune in repairs, so I'm wondering whether to change the turbo, fit a new or remanufactured one, or get a new CHRA fitted. Or could it just need the pipes clearing out?? Any advice appreciated.

Hi Andy, yes they are working fine just paralleled with the sidelights, as described above. I've got CAN-bus compatible LEDs in the sidelights, so the current drain is just fine, no warnings. The units I've used are these; not 5W but bright enough to be easily seen in reflection from car in front in daylight. http://www.ebay.co.uk/itm/2X-5W-SMD-5-LED-Daytime-Running-Car-DRL-Front-Fog-Lamp-Driving-Light-White-12V-/390600209701?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item5af1963525 I'll post a pic when i have one.

One of my rally cars had a seriously bright main beam indicator that could not be changed. A small piece of insulating tape over the indicator did the trick! Works for the lamp fail too. My wife has a Golf and the "lamp fail warning" lights intermittently. Check all the bulbs - they are fine, all working, no flickering. No LEDs just conventional bulbs. WTF???

"Thing is they are not 50w at 12v Each led runs at around 3v at 5w (for example) so 4 of them together (in series) will run at 20w light output but still only draw 5w total at 12v." w - watts - is the amount of electricity they use (volts * amps). Light output is measured in lumens not watts - so you dont have 20 watts of light. If you could get 20W out from 5W in you could sell electricity. And you cant run 4 in series from 12V - each NEEDS 3.6V. 4 * 3.6 = 14.4V "I think these draw around 8-9 w total at 12v" so they would correctlt be 9W lights, not 50W. If the company are SELLING them as equivalent to a 50W bulb, thats different. But they arent. They are claiming they use 10 5W CREE LED chips. However a conventional 50W car headlight bulb prodiuces around 1400lm (lumens - of light) http://www.durhambats.org.uk/about_torch.htm a 9W LED produces at best only about 1000 lumens. So its still not correct.

Similar issue, the fault turned out to be ONE of the number plate lamps. not obvious and not something you might think of to check!

Translator - no just some mistakes corrected. 1: the resistor you use to prevent a bulb error showing simply matches the current drawn by the LED lamp to that taken by the standard filament lamp. "The normal P13W bulb has a cold resistance of about 2.7 to 3 ohms, when it is hot 21w at 13.6v is a current of just over 1.5A, which works out at 8ohms, so a 10ohm ballast resistor would not load the control unit any more than a P13W filament bulb." (Thanks Cropwell, saved me working it out) 2: "but if they are not bifilar or Ayrton-Perry wound then they would have an undesirable inductive component. This would manifest itself as an impedance at switch on as the build up of the magnetic field opposes the current. The spike would be formed when the current is switched off as the collapsing magnetic field generates a back-emf spike. This is easily quenched with a capacitor or diode. This back-emf pulse is more likely to damage the J519 unit." There I must disagree, Cropwell. A low resistance wirewound resistor is not the same as an induction coil! An ignition coil has a primary inductance of 8mH. The resistor has far fewer windings, and (this makes a BIG difference) does not have an iron core. I have measured the inductance of a 10 ohm 10W wirewound and it was around 0.0012 mH. Too small to be any more significant than the inductance of the connecting wires. (it doesnt HAVE to be a coil to have inductance) 3 so basically as far as the control unit is concerned, there is no measurable difference between an LED lamp + resistor, and a conventional bulb. And no way of "fooling" the control unit other than drawing the same amount of power as the standard bulb would consume. Shame.

Unlike bulbs, which run happily at very high temperatures, LEDs need to be kept cool. http://en.wikipedia.org/wiki/Thermal_management_of_high-power_LEDs I cant believe a "50W" LED - or even a "30W" LED bulb with a little bit of metal in an enclosed lamp would stay cool very long. Has anyone measured the current to check the wattage? "do you think they run close to the filament bulb temps"? LED lamps are destroyed when the CHIP reaches 150C. Not the housing, the chip. Halogen capsules work at over 250C!. Their useful life is dramatically reduced when the temperature exceeds 55C. Halogen capsules need to be over 250C for the halogen cycle to work!.

Took the plunge, had egr mapped out & eco+ remap. 5000 miles, never a problem, good economy and goes like stink! money well spent.

Now at Pulman VW who believe the fault is in the EGR cooler. I didnt even know it had one! Apparently they can get blocked.

Disconnected the EGR and it worked fine for two weeks. New EGR valve and BINGO! problem solved... NOT! The old EGR was quite dirty and the exhaust gas inlet was sooty - even though it had recently been cleaned. A few longish trips later and --its doing it again!. Intermittently. Ok we've eliminated the EGR as the fault. Now the turn of the vacuum system. My reasoning - low pressure opens the EGR. Sticking open could be caused by 1: the solenoid valve not workng properly 2: problem with whatever allows air back into the EGR so it can close. FOr my readers - £470 for an EGR delete kit is looking really good value!

Yeah OK £75 + etcs well spent - then £400 for a remap? I can get new EGR for £50 ebay! All I'm asking is -is it the EGR that fails, or could it be .. the solenoid valve? .. or something else?? I dont want ot go ON replacing parts!

It happened again! About a year ago I started this thread http://www.briskoda.net/forums/topic/248027-misfire-and-black-smoke-on-diesel-19tdi-at-140k-miles/?hl=egr+valve#entry2948130 "For some time now my Octy has had a slight intermittent "hiccup" in low gears at around 2000 rpm. Only occasional but sometimes quite sharp. Recently there have been three or four occasions when it would not accelerate above 2k rpm. It also seems more prone to stalling." Well, it happened again. Only getting 30mpg - on a diesel! So I took it back to the garage and they put it on the diagnostics. No fault showed. and they cleaned the EGR valve. £40 Ran better but didnt cure problem Back to the garage and the tech discovered bad readings from the MAF. SO they replaced it. £140 Ran better but didnt cure problem Could it be the turbo? 2 bottles Forte Turbo cleaner in the tank £30. I can hear the improvement in the turbo. .. - but didnt cure problem. Looking back at my last thread I disconnected the egr vacuum pipe. AND THE PROBLEM - - black smoke, hiccups, no accel - has gone! MPG now 50 on a run. Getting to 70mph no bother (and beyond! shh!). Of course the engine warning light is now on. So my question - do I have a faulty EGR, or is there something that controls the vacuum feed to the egr that could be faulty? Or is the engine management system seeing the "fault" and doing something different?

Its just ACHING for biohazard wanings! http://www.spreadshirt.co.uk/white-biohazard-t-shirts-C4408A6626102#/detail/6626102T6A1PC10627087PA4

"LED lamps are very bright to look at, but useless as headlights" for two reasons: 1: a HID 35W lamp emits 2800 lumens from a very compact isotropic source - which is easy to focus accurately to get a similar light output from a LED you need a larger source. Its VERY expensive; and because of the size beam control is not as good. You CANNOT use a LED lamp in a headlamp unit designed for a filament lamp - the beam pattern will be cr*p. 2: when you are using 55W in a small space it gets HOT. a HID or high-efficiency Xenon filament bulb will run happily at well over 1000C. An LED will burn out if the die reaches 120C. Keeping the die cool is a problem. http://www.durhambats.org.uk/about_torch.htm http://megamanlighting.com/Technology/Thermal-Consideration

Havent got a maxidot. "It's been discussed on here a lot" - strange I didnt find it when I did a search. however I've found some now! http://www.briskoda.net/forums/topic/263164-wing-mirror-question/page__hl__+door%20+mirrors#entry3155204 http://www.briskoda.net/forums/topic/266303-door-mirror-setting/page__hl__+door%20+mirrors#entry3145228 etc. I can only assume that the setting has changed as I've never noticed this before. Thanks for the help.

To eliminate the egr valve just remove the vacuum pipe and plug the end. if it fixes the problem its the egr valve. QED.

recently I've been having problems adjusting my mirrors on the driver and passenger doors. I turn the control to set the drivers mirror - and it turns - and so does the passnger mirror. Then i turn it to set the passenger mirror - and it does. Eventually by juggling between them i get it right. Then my wife takes the car out - and I hve to do it all over again. Has anyone else had this problem?

now they are affluent so you see them driving fast cars - and because the car can do 180mph they think they sit in the overtaking lane doing 30. "the wind resistance isn't significantly different as long as the average speed isn't significantly different." and by that same reasoning we can eliminate all variables. The arrow can nevr reach the tortiose!

Likely you dont need a new one, plenty places around service them at reasonable cost.. Go on google maps do a search for alternator repair near <your city> I found a few locally. alternator repair kits are typically £5 to £20: http://www.jcrsupplies.co.uk/products/ALTERNATOR_REBUILD_PARTS/ALTERNATOR_REPAIR_KITS_AND_COMPONENTS I dont think its a massive job to replace one.

Garage should have a pressure tester for the coolant system. You need to pump it up to about 12-15psi. That should show any leaks. My guess is they've run around locally getting parts etc never got it stinking hot. Insist they fix it PROPERLY and provide receipts and service log entry for the work done. "He also told me that the head is fine and been checked" is that on the service history? why was it taken off? You dont go to all that work and expense (new gasket, bolts etc ) for no reason. Looks more fishy by the minute. My gut feeling - tell em to stuff it.

You are comparing pulse and glide with a much higher average speed to steady speed cruising at lower. In your original calculation set compares 50mph cruise with 50-70mph P&G. Which gives a 60mph average speed. Sorry its a typo; but the calc is for pulse to 70 and glide to 30. OK is extreme but the calc is only for drag. however it is the same average speed. The next error is using a diesel BSFC plot to discuss petrol fuel saving methods. Well, my car IS a diesel. OK we'll agree to differ.

Very true Jock. Its a bit academic in the real world, where bends, hills, other traffic, road works .. all prevent you from maintaining even a constant speed. And as for a measured "pulse and glide" well, I think its enough just to cope with driving responsibly. without having to watch the speedo and mpgometer all the time. and thinking ahead and planning your driving I feel is not just about improving fuel economy but also about showing real skill as a driver, and delivering a smooth journey for yourself and passengers. Very satisfying when you coast up to lights from a way off and they change to green just as you reach them -- too right!

..The physics does work and the practice does work. .. Can you give some PROPER references for that? You've tried to simplify the model .. yes I've ignored factors that have less effect than conservation of energy and increasing air resistance. For the purposes of calculation every real-world model in physics (other than simple stuff like the Schrodinger equation for an electron in a box) NEEDS to be simplified. The effect of air resistance is easily shown to be significant. Drive your car at a steady 30mph on a flat road. Take the fuel consumption reading from the trip computer. Now do the same at 40, 50 and 70. use your gears to try to keep the rpm near 2000. Plot the results and note that fuel consumption increases DRAMATICALLY By contrast, the effect of changing load from 25% -50% - 75% is only a 6% increase away from the "sweet spot" see BSFC fig http://pics.tdiclub.com/showphoto.php?photo=11194&title=fuel-consumption-map&cat=500 Thats why I ignored this element. However I'll be interested to see your calculations and a summary of the factors your model leaves out. Interesting discussion here http://ecomodder.com/forum/showthread.php/got-2-25-l-100-km-104-36-a-22054.html

I've just drive home now from where I was it was let's say a 20mile journey and I've got home and checked the water and the level is exactly where i had filled it up earlier so kinda confusing me AAAARRRRRGGGGGHHHH! Not a surprise. Often water only leaks out when the system is under pressure (ie VERY hot) A 20m trip in feezing weather wont do it. When you next go for a run, dont use the heater, get it stinking hot, then pull in and look for water coming out. If your losing water and its not leaking out its probably the head gasket. Be warned, they wll probably just fill it full of RADWELD - make sure they do a proper repair! Hope all goes well at the garage.

.. You get the best economy cruising because you haven't been able to pulse and glide properly. So properly is . . You ACCELERATE the car (using fuel) then you "glide". The engine does MORE work when you are accelerating the mass of the car. Keep the speed constant you dont have that unnecessary work. (work = energy = used up fuel) Also, the engine must work harder to overcome air resistance. the "drag" is proportional to the SQUARE of the velocity. Thats the main reason why you get better economy at lower speeds. Lets say you want to average 50mph for an hour. 1 * 50^2 = 2500 Using pulse & glide you need to accelerate gently to 70 and glide to 70 repeatedly. Say each phase takes 5 min. Then in 1 hour you do 6 pg's 0.5 * 70^2 + 0.5 * 30^2 = 0.5 * 4900 + 0.5 * 900 = 2450 + 450 = 2900 The physics proves it doesnt work. Tests "IIRC Top Gear and Myth Busters have both disproved this being effective" prove it doesnt work Hopefully this silly myth is now put to bed.