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 Post subject: Slow starting
PostPosted: Sat Aug 04, 2018 3:02 pm 
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I've noticed of late that my car seems to spin over more than it did to start when its cold. For whatever reason its worse when sitting outside in the sun, but the engine's cold, than it is when it's in the4 garage over night.
Usually it sins a couple of times and starts but on occasion its now a few seconds. So far its always started and runs fine.
Hot starts are fine.
Fueling seems most likely do you think? Its a slightly modified turbo but one thing I haven't changed is the fuel pump but it does have a newer 3 bar fuel pressure regulator.
Its almost as if it needs to pressurise the system before it starts.
Not keen on the fuel pump dying and leaving me stranded.


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 Post subject: Re: Slow starting
PostPosted: Sat Aug 04, 2018 8:39 pm 
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On my 2.5 it was a combination of things, an elderly too small battery & the earth strap from the battery going high resistance. A new battery of the right size made a huge difference.
Also the DME isn't the most up to date so it has to rotate I think a full revolution before it gets timing & starts doing its job.

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 Post subject: Re: Slow starting
PostPosted: Sat Aug 04, 2018 10:47 pm 
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Thanks Jim. The battery isn't that old, a year and a bit and I think the DME is new ish. I have one or two kicking about but I do wonder about investing in one of these solid state ones.


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 Post subject: Re: Slow starting
PostPosted: Mon Aug 06, 2018 8:40 am 
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There is a none return valve on the output side of the fuel pump that should hold pressure in the lines. If this is failing then when you go to start the car after a period of standing the pump will have to prime the fuel lines again causing a delay in starting. Easy enough to check if you have access to a fuel rail pressure tester. There is a good set of instructions on Clarkesgarage.com

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 Post subject: Re: Slow starting
PostPosted: Mon Aug 06, 2018 9:32 am 
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DavidL wrote:
Thanks Jim. The battery isn't that old, a year and a bit and I think the DME is new ish. I have one or two kicking about but I do wonder about investing in one of these solid state ones.

You misunderstood me as I wasn't clear. The DME is old technology, so you will never get the instant starting that more modern stuff does.

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 Post subject: Re: Slow starting
PostPosted: Mon Aug 06, 2018 9:51 am 
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I believe one of you is talking about dme and the other dme relay .


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 Post subject: Re: Slow starting
PostPosted: Tue Aug 07, 2018 10:34 pm 
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Prophead wrote:
There is a none return valve on the output side of the fuel pump that should hold pressure in the lines. If this is failing then when you go to start the car after a period of standing the pump will have to prime the fuel lines again causing a delay in starting. Easy enough to check if you have access to a fuel rail pressure tester. There is a good set of instructions on Clarkesgarage.com


Something along these lines does seem to fit the symptoms; refilling/pressurising the system before it starts. I don't have that kit but someone I know may have.
Thanks


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 Post subject: Re: Slow starting
PostPosted: Tue Aug 07, 2018 10:35 pm 
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tr7v8 wrote:
DavidL wrote:
Thanks Jim. The battery isn't that old, a year and a bit and I think the DME is new ish. I have one or two kicking about but I do wonder about investing in one of these solid state ones.

You misunderstood me as I wasn't clear. The DME is old technology, so you will never get the instant starting that more modern stuff does.


I think I did. Usually it spins about 3 times and boot full of throttle and it starts. A bit longer now and independent of throttle input.
My FIL always seems to have the car moving before the engine starts. A brand new car.

sgl1966 wrote:


I believe one of you is talking about dme and the other dme relay .

Again correct I think.


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