Trouble Starting Car with the issue still undiagnosed
Discussion
Hello everyone, this is my first post on PistonHeads which my father suggested to me as a reliable site of enthusiasts one of which he is!
Here is my dilemma and if anyone can help point me in some sort of direction as to the potential issue I would be greatly appreciative!
I have an Audi A4 S-Line 1.9 TDI (2005). I have sent thousands on this car as I'm a fixer not a scrapper. The problem appears to be a simple one, the car intermittently doesn't start first time and can crank for up to 20 seconds before firing up.
It isn't just on a cold start, it can happen if I leave the car for half an hour after driving it for a while. The issue is totally random.
It is regularly serviced but when the head gasket went 2 years ago I had that done along with the cylinder head, cambelt & pullies, water pump, thermostat and turbo. The glow plugs and battery are also new. NOTE: ever since the head gasket and other work was done the car hasn't fired up as smoothly as it did before but pretty much straight away.
I have taken it to my local garage who did diagnostics and could only find one of the glow plugs was dead so this was replaced and is working fine. The mechanic seemed at a loss as to what it could be so I took it to Audi to diagnose assuming they would have gadgets main dealers can only have (expensive mistake, £350 to tell me they don't know and that I should just start changing parts of the engine until the issue is found, which is so uneconomical)
Both garages ran diagnostics but could not find a fault and I have also run my own ODB just to check but nothing shows up. Audi did find that 1 of the blanking plugs by the camshaft was missing and one was loose but thye didn't seem to think this was the route of the problem just something which needs doing. Here is a link to the "AUDI CAM" video where you will be able to see what I am talking about (FYI they wanted £1k to do the work suggested in the video):
https://www.youtube.com/watch?v=xjXh4ZembfU
There are no fluid leaks and once the car is running it runs okay, the engine might might miss a beat when idling every 20 seconds or so. I have used easystart on it once and that helped start the engine so not sure if that rules anything out.
I think that covers everything. So if you have any advise on what the best next step is please get back to me. Any suggestions as to what it might be, surely there can't be many more things under the bonnet to replace!
Thanks in advance
Kind Regards Patrick
Here is my dilemma and if anyone can help point me in some sort of direction as to the potential issue I would be greatly appreciative!
I have an Audi A4 S-Line 1.9 TDI (2005). I have sent thousands on this car as I'm a fixer not a scrapper. The problem appears to be a simple one, the car intermittently doesn't start first time and can crank for up to 20 seconds before firing up.
It isn't just on a cold start, it can happen if I leave the car for half an hour after driving it for a while. The issue is totally random.
It is regularly serviced but when the head gasket went 2 years ago I had that done along with the cylinder head, cambelt & pullies, water pump, thermostat and turbo. The glow plugs and battery are also new. NOTE: ever since the head gasket and other work was done the car hasn't fired up as smoothly as it did before but pretty much straight away.
I have taken it to my local garage who did diagnostics and could only find one of the glow plugs was dead so this was replaced and is working fine. The mechanic seemed at a loss as to what it could be so I took it to Audi to diagnose assuming they would have gadgets main dealers can only have (expensive mistake, £350 to tell me they don't know and that I should just start changing parts of the engine until the issue is found, which is so uneconomical)
Both garages ran diagnostics but could not find a fault and I have also run my own ODB just to check but nothing shows up. Audi did find that 1 of the blanking plugs by the camshaft was missing and one was loose but thye didn't seem to think this was the route of the problem just something which needs doing. Here is a link to the "AUDI CAM" video where you will be able to see what I am talking about (FYI they wanted £1k to do the work suggested in the video):
https://www.youtube.com/watch?v=xjXh4ZembfU
There are no fluid leaks and once the car is running it runs okay, the engine might might miss a beat when idling every 20 seconds or so. I have used easystart on it once and that helped start the engine so not sure if that rules anything out.
I think that covers everything. So if you have any advise on what the best next step is please get back to me. Any suggestions as to what it might be, surely there can't be many more things under the bonnet to replace!
Thanks in advance
Kind Regards Patrick
The lights buzzer and internal light work as they should when the door is opened. I will try the next few journeys and leave a gap between turning the keys and ignition. Would that point towards the fuel filter then?
I will also check the lift pump. Is there a certain way to test that?
Thanks so much for the help
I will also check the lift pump. Is there a certain way to test that?
Thanks so much for the help
You're probably leaving a gap anyway while you're waiting for the glow plug light to go out
Just try a little and see if it helps to allow the pump to prime and get the fuel pressure up.
Another possibility the the Engine Coolant Temp sensor. That doesn't always show a fault but can cause dodgy starting.
Just try a little and see if it helps to allow the pump to prime and get the fuel pressure up.
Another possibility the the Engine Coolant Temp sensor. That doesn't always show a fault but can cause dodgy starting.
Hi, I meant to say that the garages have both run VCDS tests and nothing has shown up (I ran an ODB check), hence I am dubious about the camshaft/timing (hoping and praying it's more simple)
I will clear out the mass sensor & throttle and check the fuel pressure.
Does anyone know where abouts the fuel pressure check valve is situated on this model of Audi (1.9 TDI 2005 B7), that way I would know if the lift pump or fuel pump are at fault right? Then I'll change the filter either way and hopefully on eof these will be the issue.
I will report back in a few days.
Thanks for all the help and knowledge so far.
Kind Regards Patrick
I will clear out the mass sensor & throttle and check the fuel pressure.
Does anyone know where abouts the fuel pressure check valve is situated on this model of Audi (1.9 TDI 2005 B7), that way I would know if the lift pump or fuel pump are at fault right? Then I'll change the filter either way and hopefully on eof these will be the issue.
I will report back in a few days.
Thanks for all the help and knowledge so far.
Kind Regards Patrick
So after testing the fuel pump resistance it is kicking out a reading of 10:
According to this video it should be between 1 and 3:
https://www.youtube.com/watch?v=qV78c3TjzQA
So I just wanted to clarify that the issue is definitely the fuel pump if this reading is at 10? I'd imaging that it can only be the fuel pump but might this reading be showing up because of the lift pump and through to the fuel pump or is this simply not possible?
When taking up the fuel pump cover it was clear to see that Audi had not tested this as it was full of dust and the cover had to be prised open. Charlatans!
Anyway I am just looking for any further issues which it might be before forking out for a new fuel pump
Kind Regards Patrick
According to this video it should be between 1 and 3:
https://www.youtube.com/watch?v=qV78c3TjzQA
So I just wanted to clarify that the issue is definitely the fuel pump if this reading is at 10? I'd imaging that it can only be the fuel pump but might this reading be showing up because of the lift pump and through to the fuel pump or is this simply not possible?
When taking up the fuel pump cover it was clear to see that Audi had not tested this as it was full of dust and the cover had to be prised open. Charlatans!
Anyway I am just looking for any further issues which it might be before forking out for a new fuel pump
Kind Regards Patrick
Does the pump stop again after starting when you turn it on?
If so, then it is "getting up to pressure correctly" so should be OK, if it were to run & run then it isn't delivering enough fuel to pressurise the fuel system correctly.
As yours is not a Passat, do you know the pump is the same?
If not the test may be irrelevant, is his a petrol or diesel? He doesn't say unless I missed it.
If so, then it is "getting up to pressure correctly" so should be OK, if it were to run & run then it isn't delivering enough fuel to pressurise the fuel system correctly.
As yours is not a Passat, do you know the pump is the same?
If not the test may be irrelevant, is his a petrol or diesel? He doesn't say unless I missed it.
Hi, I believe that model of passat and my audi A4 essentially have the same fuel pump systems and engines.
I have run into a slight issue with testing further as the car now simply not start after a little spray of easystart (only the 3rd time the car has had some)
Here is a video to illustrate:
https://www.youtube.com/watch?v=D5VCGut6rIc&fe...
I think i'm going to go ahead and change the fuel pump and filter however now it won't start and there will be easystart in the engine is there anything I need to do before or after installing the fuel pump and filter so the car starts? Or if the issue is the fuel pump will it simply work as it should and flush the easystart through? I'm thinking the engine might need to be primed or something.
I am determine to sort this car out!
Thanks for all your help so far
Kind Regards Patrick
I have run into a slight issue with testing further as the car now simply not start after a little spray of easystart (only the 3rd time the car has had some)
Here is a video to illustrate:
https://www.youtube.com/watch?v=D5VCGut6rIc&fe...
I think i'm going to go ahead and change the fuel pump and filter however now it won't start and there will be easystart in the engine is there anything I need to do before or after installing the fuel pump and filter so the car starts? Or if the issue is the fuel pump will it simply work as it should and flush the easystart through? I'm thinking the engine might need to be primed or something.
I am determine to sort this car out!
Thanks for all your help so far
Kind Regards Patrick
I had a similar fault and as others have said, mine was the lift pump and showed no errors on the dash but it did cause funny driving characteristics as well though when it got REALLY knackered. I rolled the dice and replaced it which fixed the problem but the proper way to do it would have been to test fuel pressure which would have been expensive as I don't have the kit to do it myself.. If you're lucky you'll have separate fuel regulator on the rail which might be playing up but if you're unlucky it'll be part of the pump itself and the whole lot will need changing.
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