Car wont start.

[STU3Y]

Had my turbo done a couple of weeks ago and everything has seemed fine until a week ago when car had sat for a few days and wouldnt start.

Used torque to scan it, no fault codes so called Rac.

Mechanic arrived within 15 min, seemed very knowledgeable and very into his cars. Drove a 300bhp S3.

No fault codes on his device either. He mentioned something about fuel backing up or similar, all made sense when he said it. He said he had a few recently that have done it.

He managed to get it started with a spray of easy start and ever since its been fine.

Having sat for 3 or 4 days again it wont start.

Any one got any ideas? Fast replies appreciated

Car is Seat Leon 2.0 TDI ref sport pd140 2007.

 

[Dan FR]

Checked sensor readings in Torque? CTS reading correctly?

Do you usually hear the lift pump prime before starting? if so, does it still do it now? If its a fuel issue the lift pump should be priming the system for starting.

 

[STU3Y]

I normally hear a slight buzz if that's what you mean and its still doing it. I also hear what sounds like a valve opening and closing with a cycle of the ignition. How do I check sensors on torque and what is CTS, I don't really know much about mechanics etc

 

[STU3Y]

Just tried to turn over again and this time it bleeped and oil light came on and started flashing. Checked dipstick it seems fine

 

[Dan FR]

Oil light will come on after like 10 seconds of cranking. CTS is coolant temp sensor, can affect start but not by this much i wouldn't have thought.

I would check fuel system is being primed, taking a fuel pipe off, post fuel filter and seeing if you get a nice squirt of fuel on either ignition prime or cranking of engine. Be ready to catch the fuel in a clean container though. Adding a clear in-line fuel filter will help visual inspection of fuel flow.

Aren't fuel injectors common to fail on these? Recall done?

 

[STU3Y]

Rac arrived. different guy to last time. This one is a useless tw@. sprayed his easy start in, fired up. White smoke out back but cleared after few secs. I asked him if that was normal and he said probably unburnt diesel. He then revved the sh!t out of it...great thanks! that was very good for my new turbo on a cold engine.

He checked for codes but only cos I asked him 3 times too. No faults shown. He then said would have to take it a specialist vw garage to get it properly diagnosed.

He mentioned problematic injectors and said theyre 500 each so pray its not that. Other than that suggested a fuel filter change just in case.

 

[STU3Y]

Unknown if recall done. Could you upload a photo of where to check for spray as I wouldnt want to touch anything unless I knew it was the right bit

 

[Crafoo]

Wasn't this brought up on another thread the other day?

Did the cam shaft sensor get checked?

Would certainly stop the car from starting and would cause the engine to cut out randomly also.

 

[STU3Y]

Not by me. Sensor not checked. Mine has never cut out and runs wells when going but, just won't start when its sat for a few days.

Just asked the guys who did my turbo if anything they touched or removed could affect it and they said nothing that would cause it not to start

 

[Crafoo]

Must have been someone else then.

Might be worth a check anyway, does the car even attempt to turn over when you turn the key?

 

[STU3Y]

it cranks continuously but wont start. Just spoke to a specialist vw garage who said he thinks could be related crankong speed as it has to have a cranking speed of 250 or above otherwise wont start. Could be starter motor, fuel pump etc but difficult to diagnose until does it again. He really knew his stuff and even said rac mechanic can ring him next time, or I can leave it with them for a few days til the problem repeats and they will diagnose it then

 

[MJ]

Crank sensor would be one place to look. When it fails to start see if the rev counter rises with the cranking speed, if not the sensor (or wiring) require attention.

BKD is not subject to the same injector recall that the BMN engines are mate.

 

[shnazzle]

Battery needs replacing

 

[Dan FR]

it cranks continuously but wont start. Just spoke to a specialist vw garage who said he thinks could be related crankong speed as it has to have a cranking speed of 250 or above otherwise wont start. Could be starter motor, fuel pump etc but difficult to diagnose until does it again. He really knew his stuff and even said rac mechanic can ring him next time, or I can leave it with them for a few days til the problem repeats and they will diagnose it then

Its not cranking speed, unless its really slow and sounds like its struggling to turn over. Below 250rpm is only an issue when warm, known as the VAG hot start problem

Crank sensor is a good shout though, although not sure why it would only present a problem when the car has been stood? Id also check fuel flow next time it plays up too to determine if it could be a fuel supply issue. VCDS would be handy to check for any electrical/sensor abnormalities that would prevent it starting

 

[STU3Y]

Wasn't this brought up on another thread the other day?

Did the cam shaft sensor get checked?

Would certainly stop the car from starting and would cause the engine to cut out randomly also.

Actually thnk I did mention it on what did you do to mk2 thread but didnt go any deeper than that.

 

[STU3Y]

Its not cranking speed, unless its really slow and sounds like its struggling to turn over. Below 250rpm is only an issue when warm, known as the VAG hot start problem

Crank sensor is a good shout though, although not sure why it would only present a problem when the car has been stood? Id also check fuel flow next time it plays up too to determine if it could be a fuel supply issue. VCDS would be handy to check for any electrical/sensor abnormalities that would prevent it starting

Chap in the garage said the car can actually sound like its crankong fine but still be too slow. he said even if cranks at 249 it wont start.

 

[STU3Y]

Crank sensor would be one place to look. When it fails to start see if the rev counter rises with the cranking speed, if not the sensor (or wiring) require attention.

BKD is not subject to the same injector recall that the BMN engines are mate.

Hiw exactly do I check the sensor, or is it how you described?

 

[Dan FR]

Only when the car is warm, the fuelling maps differ depending on coolant temp. When its warm he is correct, even 1rpm below the specified figure (varies depending on temperature, from memory when coolant is above 70 degrees c its 250rpm).... for about 10 seconds when the ecu will then move to an alternate map where it will provide fuel and the car will eventually start. What he is describing is the hot start issue and is NOT the cause of your problem

Unless the car is turning over so slowly that it wont 'catch' and fire up, but you would hear this and the starter would be audibly slow

 

[STU3Y]

Battery needs replacing

No one has actually checked this but all said wont be battery cos its turning over well enough.

 

[STU3Y]

Sorry for my lack of knowledge but just to clarify are crank sensor and cam shaft sensor different. how do I check them and how easy is it to do