a real mechanic, not just a parts changer, getting rare....
@donjulio5045 Жыл бұрын
*Good luck even finding a good parts changer nowadays...I'm lead tech and all we getting applying is lazy lube techs that sit on their phone all day*
@alainmiclette7634 Жыл бұрын
@@donjulio5045 good time to ask for a raise...it's been eons salaries have fallen back on real cost of living...
@charleshoward14752 жыл бұрын
You may have just have saved me a small fortune. I was losing hope to an extent. I drove the car parked it up, then it refuses to start that Evening. Servicing has been kept bang up to date. Interestingly its timing belt, and water pump were replaced only several weeks ago. It has been such an easy starter to date, and was seemingly running nicely. It delivered 65.2m.p.g running up to Morecambe and back to Cornwall. I've precious few pennies to replace the car with at this time. If Your advice pays off here Gerard I will really need to send you a decent drink Sir.. Thank You so very much for posting a clear concise video.
@sufyanmohsin44859 ай бұрын
any updates ser?
@eddiebaldonado639Ай бұрын
Q?
@larryallsop93303 жыл бұрын
Thank you, you clever man. Unplugging the camshaft sensor was the clue I needed when I had been looking for a fuel fault. If you were here, I’d buy you a drink.
@evertspies33458 ай бұрын
If there is still no start with sensor unplugged do I then follow up fuel problem?
@evertspies33458 ай бұрын
Exactly what I did. In my case pointed to no fuel from pump in tank. While following to replace pump came across bad wiring.
@felixkalox76378 ай бұрын
Mine is doing the same thing need to do that tomorrow morning I was about to buy fuel pump but let me try this
@d1userАй бұрын
@@evertspies3345 where was the wiring bad?
@leehargitt3539 Жыл бұрын
Thank you so much!!! My 2000 Jetta tdi with 419,000 miles (that I put on it) wouldn’t start today. So while I was in a parking lot I watched your video and it was just what I needed to diagnose the problem. My fuel injection pump pulley had slipped 1/8 of an inch from the last time I did a timing belt change a year ago. So I grabbed a socket set and a couple wrenches and 15 minutes later it fired right up and I was able to drive back home 😀.
@liloskii48102 жыл бұрын
This is the exact issue my car is having now I finally have some direction and know how to handle this. Thank you so much you have saved me so much money
@dankelly92336 ай бұрын
How did you get on? I’m having the same issue
@liam-lh2nm Жыл бұрын
Brilliant video wish you worked at my work im a young apprentice and need someone like you at my work. Very good explanation and really helpful
@wochonglee219110 ай бұрын
I recently bought a cheap a vw bora 1.9tdi pd100. Took about 4 seconds to start. So I was looking around the engine bay and noticed the cam position sensor was unplugged and taped up 😮. Plugged it in and no start. Decided to check engine timing. The crankshaft pin locked in and cam was about a tooth out. Maybe a touch more. Retimed it all and plugged sensor back in bingo. Runs like a dream now.
@WholesaleTurbos7 ай бұрын
wifes old car has been sitting for 6+ months, started maybe 3-4 times and not driven. I started to drive it and noticed hard to start when cold. I popped the bonnet to check the battery charge and there were 2 spanners, thinking I left them in there for 6 months after a service, went and checked them after watching your vid and they are 13/19mm, I must have played with cam timing... without lifting a spanner to it, id say your vid has got me in the right direction
@dx_logan3 жыл бұрын
Lovely video, it's exactly the problem with my Seat Ibiza 1.9tdi 2008. I just noticed by this video that the sensor might not be the problem but yes the camshaft out of position since a cold start will make a knocking noise from the engine. Will be great after 5 mins but since the sensor is telling me something is wrong it's a lot easier to follow this amazing video before blindly buying a new sensor. A 10000000 thanks to you !!
@stevenhyatt36092 жыл бұрын
Mine at cold start taps for about 5 seconds then goes away.
@forgottenknowledge8917 Жыл бұрын
All VAG owners become a mechanic in no time, hahaha. I've learnt a lot about TDI because I bought a high mileage VW Caddy 1.9 TDI. Part after part after part has been replaced my me. Things keep breaking at 300,000km. My van is practically new now after all the work I've done to it. It's drive another 300,000kms
@modzgaming4293 Жыл бұрын
I know exactly how you feel I have a 1.9 2009 golf
@nicaragualearn39255 ай бұрын
Vw 2.5 😂😂 u right i done lots of parts and scans
@andrewnewton58932 жыл бұрын
You legend followed this video checked plug to rule wiring out 5v on all tests so adjusted torsion on cam and wow 1st click fired up
@markwatkins39593 жыл бұрын
Thank you very much My caddy has been playing up for a month or so cranking over for 30-40 seconds before starting . Adjusted the timing as it had slipped as in the video now starts 1st time
@Drewg3514 ай бұрын
Gotta drive over after the wife's 2015 TDI 2.0 refused to start. No issues so far and car has only 60K miles, barely broken in (lol). I'll definitely look into this cam position sensor.
@selloshaun36753 жыл бұрын
I’m in South African u just helped me big time...thanks bro 👍🙏🏾
@GerardBurkeBurkesGarage3 жыл бұрын
Great stuff 👌👍🙏
@neesmuparedzeets2 ай бұрын
Replaced timing belt on my golf 4, couldn't start it. Checked timing couple of times, locking tools were perfectly in place. Had the same fault about cam sensor. Checked sensor l, and thanks to your video decided to turn camshaft a bit later and it started. Thank you very much 🤟
@iankelly21103 жыл бұрын
Nice Diag Gerard good Bias voltage 5v on the signal wire the torsion values are as close to zero as possible
@GerardBurkeBurkesGarage3 жыл бұрын
Cheers for that Ian 👌🙏
@Jay-jl7by3 жыл бұрын
When testing the signal wire. Shouldn't the cam sprocket be in a certain position? Cam sensor is a potentiometer so surely if in wrong location wouldn't the 5v be pulled to ground thus sending a signal of cam position. Edit... scrap that. You run the test with sensor unplugged. Only relevant when backprobing. Good job. I've worked on loads of these and didn't realise the torsion could be so far out as to cause non start.
@DavidSmith-jb6wg Жыл бұрын
Great video Ger my car is in a garage at the moment it had a leak in a fuel line its now repaired but wont start ..
@bobirving6052 Жыл бұрын
Bleed pump and injector lines if it is ALH engine.
@DavidSmith-jb6wg Жыл бұрын
@@bobirving6052 got it sorted after a week..
@MichaelGriffis Жыл бұрын
I have a 2012 VW Passat TDI SE; I'm trying to locate this camshaft sensor connector as seen in this video at 11:34. I can not find it.
@Mind-your-own-beeswax Жыл бұрын
Nice job man. Shame I don’t have anyone like you near me who could sort out my P0028. Tried 2 different garages and neither of them seemed to have a clue.
@amarmatloob9624 Жыл бұрын
It's a 2L TDI, BMN engine 170bhp, 2006
@deansmith81710 ай бұрын
Torsion value is written in pen on the cam cover on them all, usually doesn’t last too long. Supposed to be written in the service manual too. Some can be up to 5 degrees either way, 0.0 is usually the best benchmark to adjust from when doing it.
@johnleigh34910 ай бұрын
Very informative vidio I am having a simuler problem with intermittent start up plus oil light sensor showing after new sensor fitted and an oil change help
@johnleigh34910 ай бұрын
Skoda yeti 4x4 140 bhp
@soundofsuperbad79786 ай бұрын
Thanks for this video. Does anyone know the correct torsion value for a BLS engine code 1.9 TDI in a 2008 Audi A3. I have searched but nothing conclusive. Many thanks
@kyleohara19496 ай бұрын
just shredded my timing belt a few days ago. Not sure if i did any damamge. Belt is still on but missing a whole section of teeth. ill have to check timing and see. wish me luck
@LAW-fv6ys2 жыл бұрын
For 2.0tdi 16v Inlet cam (Torsion should be 0), the exhaust cam should be adjusted so the live data for fuel consumption is flicking between 0.4-0.6 l/hr. For single sprocket 1.9tdi for example torsion is also 0
@neilappeal20 Жыл бұрын
THANKYOU 🍻
@HeimichTelemachus Жыл бұрын
Thank you very much i will try this on my BXE with hard starting issues, we changed injectors and fuel pump still same issue.
@binagarten46672 жыл бұрын
Great video. 0-0.5 is the tosrion value
@jgegere2 жыл бұрын
Great video. 0-0.5 is the tosrion value
@Sean-md6dw8 ай бұрын
I have the same symptoms about the vw tdi engine but without the fault code as well as your ,so I need to check out the fuel pump or injector.
@Dani-Innit2 жыл бұрын
My 2013 Passat TDI just started doing this a few days ago. We'll have a go at it and hope it's this simple. 😁 Ty
@Scottish_Taxi_Man2 жыл бұрын
Did it work
@AlmostAwesomeMe Жыл бұрын
i am having the same problems. had me change the fuel pump. and the problem still persists. LMK if you got yours to work
@HichamBelachgar-im2le Жыл бұрын
Please let me know if it works I have same problem with 2013 vw passat
@Drewg3514 ай бұрын
Did you get it to work ??? My 2015 2.0 TDI just quit at the mall. Cranks, won't start. Going to have to check this out.
@philfjfry12 жыл бұрын
I have same issue. Its all the way to the left. However there's markings from who has changed it previously and it lines up with them. Should I still move it to the centre?
@TonyBoggs-l4e Жыл бұрын
Like your videos, very helpful. Question, on your crank sensor VW 1.9 TDI 2001, both outer terminals are negative. What might be the best place for me to start looking I have no positive terminal
@lancecooper46463 жыл бұрын
We used to have a dude like you at our work but unfortunately he left & as far as I know, he's out of the trade, it's a shocking waste, he'd make an excellent trade school teacher 👍
@GerardBurkeBurkesGarage3 жыл бұрын
Thank you Lance, I appreciate the comment. It's such a shame when we lose good techs to other jobs or roles. They are needed badly these days
@stanmanguma91143 жыл бұрын
@@GerardBurkeBurkesGarage I have a jetta 6tdi it does not make start. If you put quick start on it it will start bt it does not Rev. No power at all. I tested the injectors they are 100 % correct. Vcds is showing nothing.
@bobirving6052 Жыл бұрын
Must be running to set torsion values.
@bobirving6052 Жыл бұрын
Possible MAF problem or intake air leak.
@bobirving6052 Жыл бұрын
If you have a lift pump, make sure it is providing pressure.
@abdulwahedy45692 жыл бұрын
Do u know where is inertia switch? ( Fule safety button)
@robertsmith98363 жыл бұрын
What if engine starts with easy start and runs fine. But will not start normally
@johnjrgensen7015 ай бұрын
Where do you find the figures for signal and power, shop manual?
@chrisjohnson4603 жыл бұрын
So I have a 2013 Passat tdi 6 spd manual. Once in a while after driving my car I go into a store come out and try to start it and it just cranks over. I sometimes have to let the car sit for 20-30 mins before it starts and I can drive. This doesn’t happen all the time only randomly. Also when the car is on a cold start and I start driving it bucks a little like it wants to take off. Do you think it could be the crank sensor failing? Ps no codes! Thanks so much
@dadwalker38963 жыл бұрын
Just helped me out loads on my golf thank you. More videos
@mwalsh30373 жыл бұрын
Quality work Ger, that was an out of the box diagnostic find, loved it "bualadh bos"
@careyautorepairs10 ай бұрын
Good video this brother, going to save it to my playlist now.
@BigRustyJoe2 жыл бұрын
Hi mate, great video! I unplugged the sensor and it still just turns over BUT sound as if it’s about to start any minute whereas when the sensor is plugged in it has no interest at all. Any ideas? I think best thing is to re-time it from scratch?
@bobirving6052 Жыл бұрын
If you have a lift pump, make sure it is providing pressure.
@louisville5110 күн бұрын
TRY THIS FIRST!!! I had same symptoms with 2017 transporter. I disconnected positive from battery and reconnected (reboot computer). Started straight after hasnt happened again since. 😅
@guyrosin1921 күн бұрын
Hi. I have a golf GD 63 plate. I cleaned it all out during the summer and it started fine. It’s been idle for a few months and now won’t start. My charger has not made a difference to the battery. Should I get diagnostics in it? Someone said the engine had seized but I can’t see it. Thanks 👍
@ajmalbangash8374 Жыл бұрын
Nice systematic diagnosis there. Could it still be a camshaft issue if the fault is intermittent? I've got a 2 litre tai Passat 2011 B7 that does this intermittently.
@c938695 Жыл бұрын
I'm having the same intermitent problem on my 2010 2.0T EOS
@mustafanjr2 ай бұрын
Thanks 😊 I am facing an issue with my car and I would like to know the best way to communicate this problem to you. Can I explain it to you or share more details in another way?
@badoburaz4253 Жыл бұрын
Gerard, I have a 2008 vw Passat. Was driving up until a few moments ago, I parked the car into my drive and a short while later I had to head back out but unfortunately the car wouldn’t start. The dash lights, radio, headlights are all coming on. I thought it might have been the battery in the key fob so I changed the battery in that but the car still did not start. Any ideas of what it could be?
@lolarodriquez23111 ай бұрын
I just did the exact same thing bought a new battery because I thought it was too after they did my sensor for my door it started doing this gotta try this
@chrischreezy2243 ай бұрын
I have that same problem mine is polo 1.9 tdi same engine I move it without cam sensor and it doesn't pick up well when I plug it is shut down thanks for the advice
@pauljr19654 ай бұрын
Would this be the same on a 2.0 gas engine, for a 2000 golf?
@imwmanish3 жыл бұрын
Great work nice video sir love from India ❤️👍🙏
@GerardBurkeBurkesGarage3 жыл бұрын
Thank you
@shakeeloniel88913 жыл бұрын
Hi Gerard thank you for sharing this video, Ive got a vw mk5 1.9tdi in the mornings it wont start i have to use starter spray then for rest of the day starting is fine... can you pinpoint me to a rite direction ? Any help would be well appreciated.
@Kinematographer2 жыл бұрын
never use starting spray on a diesel, you could bend a con-rod!
@darrengarsden9652 жыл бұрын
Where are you based as my golf tdi needs repairing
@waasimmirza19713 жыл бұрын
Hi I have same issue no start cold or hot on a 2.0tdi bnm engine any ideas what I should look for
@jayofman3 жыл бұрын
Same problem except mine cut out like it had run out of fuel, luckily as I just pulled into a lay-by.
@matthewnye8822 жыл бұрын
James, I had the same issues. It stalled on me and won't start. Just cranks. Did you find out what the problem was?
@kylekerr9614 Жыл бұрын
Anyone manage to solve this issue as I've got the same?
@upupandaway56462 жыл бұрын
HELLO I changed my clutch soliniod and disconnected battery ..now won't even crank .any Ideas .thank forthe great video
@sugar-3-Danny2 жыл бұрын
So will it make it out of time if u loosen the bolts
@stevebot3 жыл бұрын
I wonder how much beer was involved in coming up with the logic to prevent the engine from starting when the cam sensor is out of range versus starting with no cam signal at all.
@cbrown72 жыл бұрын
I thought exactly the same, perfect logic!!
@bobirving6052 Жыл бұрын
😅
@rosssorensen84858 ай бұрын
Thanks for informative video. However my issue is engine will crank but not start first thing. Wait 5 minutes and it starts and runs perfectly. I’ve had fuel pump replaced and ecu checked out. What would you suggest next?
@valntrss95083 ай бұрын
hello, did you solve the problem?
@Iosif.dumitru017 ай бұрын
Hi, I have a 2.0 bkd engine, it starts really slow in the morning. I changed the battery, injector orings and glow plugs, but still starts really slow in the morning, after 2 cranks.
@sebastianuchman3145 Жыл бұрын
Thanks for your video; I just got my engine running.
@samuesoeilyoriy65813 жыл бұрын
nice fix gearld. i done a lot of these non start over the years and the first thing i always ask is did the costumer put in wrong fuel 😆
@GerardBurkeBurkesGarage3 жыл бұрын
It's the right question to start with 😁
@ericamannea81482 жыл бұрын
This was the first video I found with substantial information. Thank you.
@wesv19863 жыл бұрын
So if I have the ign on and use the Muti meter the signal wire should be putting our 5v?
@fatosgashi73426 ай бұрын
Can this be a problem for hot start hessitation?
@turdpolisher841010 ай бұрын
whats it mean if you get 12.3v fully battery power with the ignition on to the plug? Pin 1 and 3
Жыл бұрын
Hello, i need eletrical diagram this car, can you help me?
@abdulwahedy45693 жыл бұрын
In my fule pump only 0.50v electric going, it should be 12v, where will be the problem?
@vsg446711 ай бұрын
Will these steps work on the 2.0? I have a 2011 that intermittently doesn’t start when it happened the p3007 code popped up but went away after it finally started
@ahmedamzil41703 жыл бұрын
Thanks for this vidéo ,what is value torsion?
@mariusrusu774110 ай бұрын
Hello and congratulation for this video. I have same problem with my Caddy, year 2010 , 1.9 TDI, 77kw, 2k ACBLSX01 engine. All the symbols appear on the board when I turn on the ignition, in this case I have excluded some releys. Like in this video I disconected the sensor but engine it still won't start. Could you give me another suggestions please? I'm not mechanical but some timebut I like to solve problems myself . Thank you I don't know if it helps but the engine has 108,000 real km on it.
@darylmiles58623 жыл бұрын
Will give this a try in the morning, hopefully it will get it started 👍
@KristijanPetrovic-q7j3 ай бұрын
Hi mate could you advice me got a vw touran 2008 1.6 fsi Reverse lights stoped working 2 daysbago yesturday the headlights comes on with ignition while headlamps relay switch is off today the car wont start any advice would be very appreciated Changed the h switch still no difference checked fuses wirh probe they seem ok
@cecilshannon25863 жыл бұрын
Thank you very much! I have been fighting with my brm for a while now. I just installed a stage 2 cam from kerma TDI and im not getting a torsion value! I am using vcds and I don’t know if I can see camshaft speed on there. I will try out a couple tips you gave in the video!
@eugeneoreilly9356 Жыл бұрын
You don't need to see camshaft speed,what you need to see is the timing limits within specified tolerance.
@cecilshannon2586 Жыл бұрын
@@eugeneoreilly9356 I got it figured out finally haha it ended up that all 3 cam sensors I got were all bad. If anyone gets one I would get it straight from Kerma. I got 2 from autozone and one from rock auto. None worked except the one from Kerma
@eugeneoreilly9356 Жыл бұрын
@@cecilshannon2586 glad you got it running.
@bobirving6052 Жыл бұрын
I bought cam sensor from Rockauto and it works fine.
@adammorley46252 ай бұрын
Mate iv changed the timing belt and sensor code gone and started and run for bit cut out got code for glow plugs changed them and now it crank try to start 1000 rpm and cuts out iv checked fuel all seems fine have no clue what is going on now nothing coming up on scanner any clue any advice would be fantastic thanks
@JohnHarryShaun Жыл бұрын
I have a 2.0 pd, cut out, won’t run, gravity fed the flow to tandem pump, and vacuum can on the return, I can’t get anything back from the return cranking or not, therefore no flow to the injectors. Do the tandem pumps fail like this???
@sugar-3-Danny2 жыл бұрын
I love you man. Solved my problem 🙏🏼💙😂
@ariantaria20653 жыл бұрын
Well diagnosed and step by step explained, great video many thanks 👍
@GerardBurkeBurkesGarage3 жыл бұрын
Thank you Arian
@doobiekutzmuzik2 ай бұрын
@@GerardBurkeBurkesGaragehey ger do you have an email i can contact you at with some questions about my 1998 sharan 2.0 petrol? Thank you mate!;-))👍🏼🙌👊💪🙏🏼
@longbar23443 жыл бұрын
my project bkd engine'd golf had it's turbo let go. found metal everywhere upto the intercooler but nothing after. replaced turbo and tried to flush oil and put fresh in. it cranks fine but won't fire, was gonna try this but my fault code is p2100 (anti shudder valve) it is clean so a bit stuck. trying to order one but would that prevent the engine starting?
@colin50643 жыл бұрын
very useful and informative video. My question to you is how can l determine on a five pin connector vw golf mk6 1.6 tdi. which pins relate to +5v and _5v on the air intake swirl valve motor. Not easy to find access to a wiring diagram for this. As l suspect the swirl motor and wish to see if it functions on the bench 6
@Gdljal24 Жыл бұрын
Hello there I have Signal on Pin 1 (4v) Pin 2 (3v) Pin 3 Is ground and my Caddy still doesn’t start but it does start with the camshaft sensor disconnected I put a new one in and still doesn’t starts
@MiracleMAX3 жыл бұрын
Nice diagnosis mate & good details 😊
@GerardBurkeBurkesGarage3 жыл бұрын
Thanks mate 🙏
@milosnackovic96073 ай бұрын
You the man👊✌️, thank you
@GerardBurkeBurkesGarage3 ай бұрын
🙏🙏👌👌
@home87062 жыл бұрын
i have the same engine and i need to ask can it just stop or can the problem get worse over a cple of days? Mine started after i parked it up drove it started making a screeching noise took home parked up was told it was the turbo but no smoke just loss of power then it wouldnt start i have smoke coming from the join to turbo and also down the air intake pipe but now it just doesnt run did show turbo boost preasure sensor fault that was it i need help
@antof12353 жыл бұрын
Once again, thank you very much
@GerardBurkeBurkesGarage3 жыл бұрын
Thanks Anthony, I appreciate it 🙏
@frenchwithmoufdi37763 жыл бұрын
U0155 error code for my passat cc 2012. I have changed the battery 🔋 but still same problem in the morning juste??
@erashio67022 жыл бұрын
Hi Gerard do i unloosen the 3 bolts or the centre bolt also the re align back up much appreciated.
@amarmatloob9624 Жыл бұрын
Hi, I have an Audi A3, cranks and just about starts and then runs rough. On acceleration it only gets going when at 3k RPM, however when it gets hot it seems to get much smoother and accelerates from 2K rpm. Has glow plug control module codes and also all injectors upper control limit reached. What can it be? Thank you
@gambit_toys6554 Жыл бұрын
I tried unplugging the crank sensor no luck. *correction* I tried again and the engine started without the sensor! Car is running 08 Touran 1.9 tdi 364000kms. Thanks!
@fieldsofomagh3 жыл бұрын
Would that engine fit into a Morris minor ? It badly needs an upgrade to gain traction down the boreen come summer time.
@GerardBurkeBurkesGarage3 жыл бұрын
😂
@madimetsalanga55255 ай бұрын
My jetta iv 1.4 just cranking. I came. With it from mpumalanga but when i arrive here at joburg. After 2 weeks when i start it it just cranking til now.
@AA-bw2hy2 жыл бұрын
My wv touran 2.0 dsg,have problem and,sometimes dont start,and one mechanik get out my radio,think radio lost energy on battery.but again same problem dont start.What doo y think?!
@andrewnewton58932 жыл бұрын
Bonus just got my golf 1.9tdi BLS engine and it starts after a while noticed cam sensor not plugged in properly she just had full cam belt kit I'll test loom and look for signs as befor this she would fire straight up
@marystevens67232 жыл бұрын
My 03 beetle is doing the no crank thing and I hope this is the answer.. thank you for the video!
@bobirving6052 Жыл бұрын
Probably air leak in fuel line or injection pump.
@johnburns64228 ай бұрын
You are Good could do with you in Letterkenny area of Donegal
@romankorol43782 жыл бұрын
I got 2006 jetta tdi and similar problems, but mine cranks really hard and doesn't start. I tried to do what you did and not start and no codes. What else could be ?
@Auto_diagnostics Жыл бұрын
Hello Gerard! Have you thought that VW stated to name their engine line as TDI in about 1992, so neither engine code, no even fuel injection system in your video's name...
@stuartwest12362 жыл бұрын
Hi am looking for a bit of advice,my wife was driving my 61 plate Octavia vrs TDI when it just turned off,took it to the garage they changed the crankshaft sensor,then said they noticed moisture about the ECU but they thought it was another sensor behind the gearbox, gearbox was removed and sensor was checked and all fine,put new clutch in car while the gearbox out, got car back been starting and stopping and then broken down again,towed to other garage and now saying car has no compression.
@WinleyKannemeyer-p7x Жыл бұрын
I have a jetta 5 tdi 1.9 my kar won't start and oil did come out my diep stick ever since never want to start?
@luismiguelgamboa92402 жыл бұрын
Good video and very well explained.
@GerardBurkeBurkesGarage2 жыл бұрын
Thank you Luis 🙏🙏
@michaelwatson95932 жыл бұрын
I have a VW Passat 2013 2.0 Tdi that will not start. Purchased a Crankshaft Position Sensor. Not sure where it is on this vehicle.
@kennethbeeler13 жыл бұрын
What a great video sir, wow!
@quietfieldvancastle69258 ай бұрын
Hi my vw crafter switch's off while driving what could be the problem