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Old 8th July 2016, 06:29 PM
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Default Fails to start.

The car has been standing around for a while and yesterday i put a new air filter in prior to doing the oil and filter today. I didnt start or move the car before or after doing the air filter. Came to start the car today to get it on ramps for the oil change and it fires up and then cuts out. BrianG suggested the immobiliser problem but I am not getting the immobiliser light. I noticed the fuel guage was showing empty (I cannot remember parking it up with so little fuel ) so went and got 5 ltrs. Still wont run. I think I can hear the fuel pump when switching on and it will fire first time, every time. But the empty gauge is intriguing me.
Any ideas? Its a fine evening and I would like to get it sorted out.
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Old 8th July 2016, 07:11 PM
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For the brief time it runs, does it run fairly smoothly before it suddenly cuts or is it more of a cough and splutter before dying (especially if you use the throttle to try to keep it running)? If it's the former, I'd suspect immobiliser, otherwise I'd suspect fuel.

Also, if the fuel level was very low, because of the unusual way the tank works, I suppose it's possible you may need to put a lot more fuel in to get the air out of the pipes.
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Old 8th July 2016, 07:19 PM
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Hi Mark,
It starts up with the usual roar and then, instead of settling back to idle, just dies. Using the throttle just increases the initial revs (as you might expect) before dying away. I would have thought the immobiliser issue was to blame ...but i cant figure this fuel gauge issue.
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Old 8th July 2016, 07:22 PM
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I am certainly aware of the complexities of the tank and the pump/venturi system - when i came back from a few weeks away the year before last i had a similar issue. got the local indy to take the car away, pull the pump out and give it a good eyeballing but they never found a fault. it worked perfectly thereafter --- until now.
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Old 8th July 2016, 07:23 PM
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These cars need a damn good thrashing every now and again... and I dont mean Basil Fawlty style - they just NEED to be driven!
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Old 8th July 2016, 07:48 PM
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That definitely sounds like immobiliser behaviour. Do you have VCDS to scan it with?

You could try cracking off the fuel feed union on the fuel rail to see if anything comes out - just loosen it a little with plenty of cloths to absorb the spillage. I wouldn't have thought it would start well if that was the issue though.

Last edited by MikkiJayne; 8th July 2016 at 07:52 PM.
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Old 8th July 2016, 08:31 PM
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Quote:
Originally Posted by David's8 View Post
These cars need a damn good thrashing every now and again... and I dont mean Basil Fawlty style - they just NEED to be driven!
They do.

Gotta give 'em some stick (not the entire branch).

They sulk if you don't drive them often enough.




That does sound like an immobiliser or electrical issue to me too. When I've had fuel tank/pump issues in the past, the brief starts were (as you'd expect) more coughy/spluttery and sometimes extendible with a bit of throttle.
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Cars Owned:
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Old 8th July 2016, 08:54 PM
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I need to get the (shared) VCDS off The Laird tomorrow and will give it a scan then.

Thanks Mikki, I was going to check fuel flow too. I have a new fuel filter to fit as part of the service routine (even the old one is less than 10-k miles old) so will do that asap.
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Old 8th July 2016, 09:50 PM
ainarssems ainarssems is offline
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You should get immobiliser warning light if it is immobiliser issue if the light is working. Another way to confirm/eliminate immobiliser is - turn on ignition and start engine immediately, so the engine starts and dies within second or 2 because it had couple of seconds of runtime before immo blocked it. Second time turn on ignition, wait 5 seconds to give time for immo to block engine running and try to start, if it still starts it's not immobiliser problem.

Considering that you changed air filter before issue started I would be looking at MAF, it's wiring and unmetered air leaks, but than again it should still run at high rpm if you applied throttle, at least for cable throttle cars but as yours is drive by wire it could still be the problem.

If the tank is empty and you put in some petrol it will drain straight into fuel delivery unit so even if suction jet pumps are not working you would get more than couple of seconds running time, at least couple of miles of driving.

It could be fuel pump or relay issue as well, my friend had a very similar issue on Ford Focus, turn on ignition, fuel pump and engine runs for couple of seconds, failing pump draws too much current and relay cuts out, engine dies. At the time at Tesco car park I swapped full beam light and fuel pump relays for him as they are the same, well actually most of them are the same on Focus but I thought full beam was the kind of thing he could get by without if it was relays fault. Both full beam and fuel pump was working then and he was driving it without an issue for several month since but had to change fuel pump eventually.

If the fuel was low it could be air in fuel lines, just try turning ignition on and off for couple of seconds at the time for 10+ times for fuel pump to prime and flush out any bubbles.



Edit


Is the car on incline? That could explain weird fuel gauge readings, still should run OK if you put 5l of petrol in it. Now that i come to think about it, if somebody messed about in the fuel tank before they might have dislodged fill tube so that it drains any entering fuel in the main tank instead of fuel delivery unit in which case you will need like half a tank before it runs properly.
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Last edited by ainarssems; 8th July 2016 at 10:00 PM.
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  #10  
Old 8th July 2016, 10:30 PM
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Thanks Ainars,
The car IS on a slight incline with the front end up the hill. The MAF was my first concern having given the airbox a good clean with the vacuum cleaner and a soft bush before fiiting the new filter.
However, I will read all that carefully and then check out all the issues you raise.
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