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Car wont start.
- Thread starter STU3Y
- Start date
Impossible to say as none of us know for sure what the issue is.
My advice - now that the MAF issue seems to be sorted, is to see how it goes, and see if the problem rears its head again. Fingers crossed one of the things youve done so far has helped and that's the end of it.
Not true at all, there is a lot more to VCDS than just code reading. If all you want is code reading there are scanners for £30 on eBay.
VCDS has the ability to display live data for pretty much every sensor and elecrtrical component on the car, a sensor can fail or start to provie an inaccurate reading and won't necessarily throw a fault code
If its not failing then u dont have an issue. Potentially you have fixed it yourself. Id give it some time n see what happens.
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Sent from my iPhone using Tapatalk
I would have thought it would be at the time the fault code is logged you would have an issue, if no fault is logged then is the part not still operating within the working tolerances?
The point is no one knows what is causing it to fail to start and only after being sat for 3 or 4 days and from what tests I've done so far it hasnt really given any clues. Plus anytime the prob occurs there are no fault codes shown.
I think either the issue is the lift pump is running weak on occasion, hence the pulsing hose and bursts of fuel (unless someone says thats normal) or maybe its my injector seals are leaking. Other than that I would have thought its battery related as I cant see why it would only occur after a few days. Something must be building up or running down during that time.
It may be within certain parameters but doesn’t mean it is reading accurately. MAFs are well known for this, usually under reading but won’t throw a fault code unless extremely bad or there is a short to ground etc.
From memory they are the 2 most likely suspects, although i would do some digging and find out where the non-return valve is (if there is one). If not, maybe buy and fit one to see if it alleviates the problem
Since I last updated my car has started every time it has been left so I have not taken it to a garage. Unfortunately today it did not start and only sat for 3 days.
The one thing I have noticed is that it always seems to be when the weather is really hot and after ive spent hours washing the car. (not sure if either have any bearing)
Today when it didnt start i tested the cranking speed on torque app and was 269. No fault codes I tried about ten times to start car with prolonged turn over without success.
I then hooked my girlf' car up to it and it still didnt start at first however after a couple of attempts of about 8 seconds each it slowly tried to fire up and then started.
Having done so it ran really lumpy and then the engine was shaking violently as if it was trying to cut out l after every few rotations like a misfire or similar. I revved it to just over 1k and it settled whilst doing this but smoked quite alot. After about 1 min at most it seemed fine and smoke cleared.
Any ideas what this could be, I am praying its not my injectors.
Also one thing I have noticed, is what, I think is the tandem pump is getting so hot very quickly to the point you cant touch it for more than 2 secs otherwise it burns you like the outside of a kettle.
Is this normal?
The next thing that I have never seen before with my car but think is probably fine is the car was dripping water underneath, alomost where the handbrake/gearstick would be. I assume its just from the aircon but never noticed it before and it was dripping so much i was leaving a constant trail down the road after one short drive. It continued to drip with the aircon off. This is where from with the cover on and off
All advice appreciated?
The one thing I have noticed is that it always seems to be when the weather is really hot and after ive spent hours washing the car. (not sure if either have any bearing)
Today when it didnt start i tested the cranking speed on torque app and was 269. No fault codes I tried about ten times to start car with prolonged turn over without success.
I then hooked my girlf' car up to it and it still didnt start at first however after a couple of attempts of about 8 seconds each it slowly tried to fire up and then started.
Having done so it ran really lumpy and then the engine was shaking violently as if it was trying to cut out l after every few rotations like a misfire or similar. I revved it to just over 1k and it settled whilst doing this but smoked quite alot. After about 1 min at most it seemed fine and smoke cleared.
Any ideas what this could be, I am praying its not my injectors.
Also one thing I have noticed, is what, I think is the tandem pump is getting so hot very quickly to the point you cant touch it for more than 2 secs otherwise it burns you like the outside of a kettle.
Is this normal?
The next thing that I have never seen before with my car but think is probably fine is the car was dripping water underneath, alomost where the handbrake/gearstick would be. I assume its just from the aircon but never noticed it before and it was dripping so much i was leaving a constant trail down the road after one short drive. It continued to drip with the aircon off. This is where from with the cover on and off
All advice appreciated?
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What colour smoke? smelt of diesel i take it? It sounds like a fuelling issue, either starvation or possibly an injector issue. I have no idea o nthe tandem pump, can't say i ever touched mine from cold/when starting the engine. VCDS would be handy here to look at the injector balance
I spoke to the vw specialist and they said it should not get hot like a kettle as its libricated and cooled by the diesel, I think its going to be the most likely culprit for my problem. On other threads people say the seal between the vacuum pump and fuel side of the pump leaks and over time the tiniest amount of air goes into the fuel side causing an air lock and forcing the fuel to drain back slightly. Thats why I wont start without easy start or til its been cranked so many times its dislodged the air lock. Would also explain the long delay, must be a very small leak. Think pumps are around 300 new
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So just got back from a 2 week holiday and car fired up first time; so wierd.
Having considered my options I have decided to try and replace the tandem pump myself and have just sourced a used one on ebay for £30. I figured having to pay someone 60 to diagnose then possibly another 300 to fix it I might as well try and rule it out this way. Assuming the new one is in perfect working order, worse case the problem persosts and I sell it again or lose 30 quid. Best case problem resolved and I save a couple of hundred.
Anyway my question today is...Ive read the instructions in the manual for replacement of the tandem pump and it says I need a hand pump for the fuel line. What exactly is the purpose of this during removal and refitting and can I still do it without somehow? e.g pinching/plugging the hose
Having considered my options I have decided to try and replace the tandem pump myself and have just sourced a used one on ebay for £30. I figured having to pay someone 60 to diagnose then possibly another 300 to fix it I might as well try and rule it out this way. Assuming the new one is in perfect working order, worse case the problem persosts and I sell it again or lose 30 quid. Best case problem resolved and I save a couple of hundred.
Anyway my question today is...Ive read the instructions in the manual for replacement of the tandem pump and it says I need a hand pump for the fuel line. What exactly is the purpose of this during removal and refitting and can I still do it without somehow? e.g pinching/plugging the hose
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Fitted the used pump today, the one on it was immaculate externally as was the gasket, put a new one on anyway. Did it without the hand pump. Amazingly started right up. Can't tell any difference in the drive. Done a couple of test drives and this one seems to get even hotter than the original, literally scolding hot, its quite worrying. (Would love some input from others as to how hot yours get after a dual carriageway run) Also couple of times took longer to crank over than normal, only a couple of seconds. Only time will tell if it has solved the problem (I'm not convinced)
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Haven't let the car sit yet since changing the pump so don't know if it's solved the non starting problem. However I have already noticed that it seems to start a little quicker when cold but now seems to be taking a good 3-5sec of cranking to start once up to temperature. Dreaded hot start problem? ANY IDEAS?
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