random engine stalling bkd tdi

[05hudsond]

i really hope someone here has faced this problem , ill try explain as best as i can my car is 2008 Audi a3 tdi 2.0 bkd, basically what happens is the engine randomly stalls on idle , when changing gears and slowing down at traffic lights but will start back up no problem ,i it was doing this stalling problem a few months ago then stopped doing it until few weeks ago ,ive had people recommend crank shaft sensor and cam sensor , now im only a newbie when it comes to cars but surely something as important as crank or cam sensor would bring some form of code and engine light ,

couple off more details to add

sometimes when setting off it will stall with the tiniest movement of the clutch peddle

sometimes it will idle at around 1000rpm instead off the normal 800 odd rpm

have noticed that having aircon on causes it to stall more frequently (aircon works fine nice and cold air),

it seems start the stalling problem when engines up to temp and really bad when its a very hot today

vcds no codes stored/ no engine management light

ive tried my best to explain as best as possible thanks in advance

[Crasher]

The crank speed sensor called a G28 is notorious for not leaving a fault code when it fails due to heat and is the only sensor that will actually stop the engine. The problem is they are a PITA to replace and if the screw that holds it in rounds out then it is gearbox out and clutch/flywheel of at the least but can escalate to sump off and needing the special seal aligning jig to fit a new holder. I keep a nice sharp SnapOff long 4mm ball ended hex key just for this job. I an not as fast as I once was but I did one on a BMN engine (the DPF 170 version) a couple of weeks ago and it took me two days.

[05hudsond]

cheers for the reply crasher , ive been following forums for a while and seen you help alot of folk and actually made an account hoping youd reply be , ill start with getting the crank sensor g28 replaced hopefully its not going to cost a huge lot of money, is this the part im looking for not sure if you can post links here but this is from uero car parts https://www.eurocarparts.com/p/starl...nsor-41944044s

[Crasher]

Yes but we only fit the genuine VW 036 906 433 E as it has a two year parts and labour warranty for £91.56. After 2008 there can be variations of number so we take the old one out first to see what it is.

[05hudsond]

https://www.youtube.com/watch?v=Sx-L...nel=DannyBTech

heres a video off my car ....its getting worse now its cutting out on cold starts ,i was about to buy the sensor last week but a friend suggested servicing it so i did , hasnt made anything better , please could you watch the video and tell me if you still think its this sensor , i only ask as moneys tight and really dont want to spend more money then is needed . if your still sure its the g28 sensor ill buy one this week and see if i can get someone to fit it

[Crasher]

Difficult to tell but the G28 would be my main suspect although the time it cut out near the end the dash went blank, was that you turning it off?

[05hudsond]

yes that was me turning it off at the end , how do i go about buying a genuine sensor i mean what website would sell them as closest audi or vw is bradford and im in halifax and dont feel brave enough driving this car that far as the cutting out problem has got really bad now , if this sensor doesnt fix it then im either gonna scrap car or try sell it as i cant afford a never ending stream off spending money i dont got on potential fixes, im really hoping this sensor fixes it..... does this website allow you to sell cars as rather not use facebook

[Crasher]

To fulfil the parts warranty you should buy it from the make dealer. I hope it fixes it, it is a lot of work if it doesn't. I did one on a Golf 5 PD TDI 70 BMN engine and it fixed the problem but then an injector failed and they are obsolete with recon ones being a joke and hard to fine as no one will touch them. The car needs a new DPF, also obsolete, clutch/DMF and potentially a new ECU, also obsolete so all my work is down the drain.

[Sammasonyamaha]

Crasher need to pick your brains if ok. can the g28 fail without any code? My mk5 gttdi170 has just broken down with nothing but ignition codes. I have replaced the ignition electrical switch cleared all codes but still it wont start. The lift pump is fine and all timing etc fine so thinking what else can stop it dead.
I did however have a fault code p0321 about a month ago for crank sensor so ordered one and cleared code but it hasn't come back.

Thanks Sam

[Crasher]

It is quite normal for a failed G28 to not generate a code, if fact when I do see one I am surprised. The easiest way o know is be alert to the cutting out and don't dip the clutch, look at the rev counter and see if it is registering an appropriate value. I had this happen to me earlier this year with a BMN 170 in a Golf 5 and it was actually a burnt through DPF pressure sensor wire.