Author Topic: G40 Cuts Out When Stopping At Junctions  (Read 4212 times)

Offline jcollyer

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G40 Cuts Out When Stopping At Junctions
« on: November 11, 2017, 09:11:39 am »
my g40 keeps cutting out when I brake to slow down at junction at first I Thought is it because the Engine wasn't warmed up but that wasn't the case I also Checked to See If Throttle cable is stretched got a new one but its still doing it has anyone got a Clue What Else it could be
« Last Edit: November 11, 2017, 11:53:04 am by jcollyer »

Offline josé

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Re: G40 Cuts Out When Stopping At Junctions
« Reply #1 on: November 11, 2017, 04:27:28 pm »
Battery would be my guess

Offline ereeiz

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Re: G40 Cuts Out When Stopping At Junctions
« Reply #2 on: December 15, 2017, 01:22:25 pm »
Checked for vacuum leaks?

Have you had anything removed/ refitted at all recently? Or within the last few hundred miles?

Checked vacuum hoses? May be a cracked / split pipe.

Offline GR40

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Re: G40 Cuts Out When Stopping At Junctions
« Reply #3 on: December 20, 2017, 12:18:07 pm »
Throttle body flange made a world of a difference with the car cutting down at junctions in my case. Their leak is usually unnoticeable. I would change it just cause they tent to harden and tear with time.

Offline alexmac738

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Re: G40 Cuts Out When Stopping At Junctions
« Reply #4 on: December 21, 2017, 11:49:13 am »
Same thing is happening to me. It's very tempramental. Car usually cuts out when idling for a few minutes as well. Battery voltages are good when off and on so can't be alternator. Been told to check Idle Control Valve but don't know where to look....

Offline hayesey

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Re: G40 Cuts Out When Stopping At Junctions
« Reply #5 on: December 21, 2017, 02:29:59 pm »
there isn't an idle control valve. 

Whoever said that probably means the aux air valve which is located underneath the inlet manifold, bolted to the water pipe.  It's job is to increase air flow and idle when the engine is cold, when it's up to temp it's supposed to close.  It's a simple valve controlled by a bi-metallic strip which loses it's springyness over the years.  If they stick then they can cause idle problems by effectively creating an air leak.  I don't think you can buy them new any more and 2nd hand ones aren't likely to be much better.  I had some limited success taking it off and soaking it in carb cleaner for a while to clean it out.

Other than this, check for any air leaks - worn out vacuum pipes, throttle body gasket etc...

Also check the ignition timing using a timing light.

Offline alexmac738

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Re: G40 Cuts Out When Stopping At Junctions
« Reply #6 on: January 10, 2018, 03:39:19 pm »
Cheers for the help guys. Managed to sort the issue by simply adjusting the idle. None of the vacuum pipes that I could see were worn down at all. Adjusting the idle with the screw managed to sort the issue, it idles a wee bit high when cold but settles down fine now :)

Offline ereeiz

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Re: G40 Cuts Out When Stopping At Junctions
« Reply #7 on: January 16, 2018, 07:05:19 pm »
Did you put it into setup mode first? Or just tweak the screw? It may be fine, but if you didn't set it up correctly you might just be masking the issue. It's a bit of a faff to do but only takes 5 mins once the car is up to temp.