Running very rough and no power

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pzscala
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Joined: Thu Jul 02, 2020 11:53 pm
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Running very rough and no power

Post by pzscala » Fri Jul 31, 2020 11:28 pm

Hi All

Having some trouble with my J reg Scala.

Was driving it the other day when I suddenly lost almost all power. Limped to a nearby estate and the car was idling at around 2000rpm. I’ve replaced dizzy cap, rotor arm and leads in the hope it was ignition and all that’s changed is that the engine now idles at around 1400rpm, and very very rough. When I rev it slowly it will build revs but again is rough, however when trying to rev it quickly (I.e a quick yank on the throttle cable) the engine chokes up and nearly dies before returning to idle. Any clues what this could be? Sounds like a fuelling problem but I’m not sure where to start with K Jet!

Car seems to start up fine and doesn’t show much improvement when it’s warmed up so I’m not convinced it’s WUR but again I’m not knowledgeable on how the system works. Going to have another look at it in a couple days in a last ditch attempt before she goes to the garage for a proper look, any help is much appreciated 😀



mark1gls
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Joined: Thu Apr 02, 2009 9:28 pm
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Location: Somerset

Re: Running very rough and no power

Post by mark1gls » Sat Aug 01, 2020 8:03 pm

A couple of ideas....
Check the fuel tank filler neck for rusty holes, take the cap off and shine a torch down it.
Air leak on the rubber hoses in the engine bay.

Did the fuel pumps start to make more noise when the problem happens?


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pzscala
Posts: 4
Joined: Thu Jul 02, 2020 11:53 pm
fill in the right answer: 15

Re: Running very rough and no power

Post by pzscala » Sun Aug 02, 2020 2:09 pm

The fuel tank definitely has issues with contamination as I’ve had to take out the lift pump and put a filter over it as it was previously cutting out, however this time the lift pump appears to be working fine - when I took it out there was plenty of fuel in the return line which suggests to me that it’s delivering enough fuel to the engine (correct me if I’m wrong though!)

I think you’re right there may be a blockage or something along those lines however if this was the case how come the car can rev well over 4000rpm when you pull the throttle slowly?

I’ll have a look for some leaks too, thanks for your help