It's been standing, now sick - idle and low power

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p in phcas
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It's been standing, now sick - idle and low power

Post by p in phcas » Thu Jul 12, 2018 6:14 pm

My Scala (injection) hasn't been getting out much recently. I last started it in October last year and it seemed fine. Now it is complaining....

It starts pretty much on the button but doesn't fast idle at cold. It has low idle at any time, cold or warm. It's low powered from 500 (yep, that low) to 2500 rpm - it stutters a bit but will pick up above 2500, better when warm. When letting the accelerator go, it doesn't drop nicely to idle, it goes below (sometimes stalling) and wheezes to get to 500 rpm.

There is fresh fuel in there but I suspect something has stuck, got gummed up or is not working in the fuel system. Visually in the metering head, throttle body, air filter, hoses and connection all look OK and parts move as I would expect. There is a slight misfire heard on deceleration...

Any clues where to look?


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mark1gls
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Re: It's been standing, now sick - idle and low power

Post by mark1gls » Thu Jul 12, 2018 11:42 pm

There is a pin which is operated by the metal flap in the meter head which controls fuel to the injectors and can rust/get stuck.
Common problem and a few guides on the web should help....


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p in phcas
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Re: It's been standing, now sick - idle and low power

Post by p in phcas » Sun Jul 15, 2018 8:50 am

The movement of the meter head plate feels fine - a little consistent resistance on the upward stroke, nothing crunchy or sticky. Its almost like air starvation rather than fuelling. I've let more air in by disconnecting vacuum lines to see if it increases the idle speed but nothing.

Could I be looking in the wrong area? Could it be ignition timing or something similar that would cause this....


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p in phcas
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Re: It's been standing, now sick - HELP still needed!

Post by p in phcas » Thu Aug 16, 2018 8:57 am

I am stumped. I have poked, checked and tinkered with the various dirty bits under the bonnet and I am no further in finding the cause of bad starting (on cold), low idle and poor power below 3000 rev.

For all intent it seems like air starvation but all pathways are clear. It doesn't smell like fuel starvation as the exhaust smells more like it is running over rich.

Any other ideas? Before being laid up for six months without starting it was running fine. My only change in between times is replacing the disti-cap and rotor arm.


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Re: It's been standing, now sick - HELP still needed!

Post by the edmundator » Thu Aug 16, 2018 7:39 pm

p in phcas wrote:
Thu Aug 16, 2018 8:57 am
Before being laid up for six months without starting it was running fine. My only change in between times is replacing the disti-cap and rotor arm.
I'd look here, then. Replacement parts aren't great quality these days and even new ones can be duff.


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Re: It's been standing, now sick - idle and low power

Post by DannyH » Thu Aug 16, 2018 10:04 pm

damp in the fuel

you could try some Wynn's Dry Fuel.


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p in phcas
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Re: It's been standing, now sick - idle and low power

Post by p in phcas » Sat Aug 18, 2018 8:15 pm

Thanks Dan. I've put some good fuel additive and new fuel in the tank. No change. Going to take a closer look at the disti and rotor arm. It is firing on all cylinders, just not very well during cold start or anything below 2500 rpm. What's the symptoms of the vacuum advance / retard mech seizing in the distributor? Would that affect running all the way through the rev range or just at certain points.


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Re: It's been standing, now sick - idle and low power

Post by haddock_n_chips » Sun Oct 07, 2018 6:06 pm

Check engine earths too,

Mine would always fire up (albeit a bit laboured) and run OK on idle but almost cut out if you blipped the throttle (revs drop right down)

Took the engine earth cables off, wirewheeled the connections and contacts. Popped it all back together and it's a million times better!

Just a thought :-)


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p in phcas
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Re: It's been standing, now sick - idle and low power

Post by p in phcas » Mon Oct 08, 2018 10:35 pm

hmmmm, that's worth a though. Will give it a try and let you know..

thx..


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Re: It's been standing, now sick - idle and low power

Post by C 20 CCO » Thu Nov 29, 2018 8:25 am

Hi,
Any news, have you managed to try any remedies to fix.


kind regards,

Dave.

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