Technical Light throttle stutter

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Technical Light throttle stutter

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Aug 4, 2010
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Car now drives spot on except ive noticed it tends to feel like a slight miss or stutter on a light throttle pulling away low down say approaching an island in 2nd then you drift into a gap but your right low down in the revs.

Is this a ropey set of coils or poor quality ones? I dont mind buying some new ones if anyone has recommemdations of where to source them and make. Obviously going to avoid the fiat dealers.
 
They say check the basics first and being lazy i only checked plugs 1 3 and 4 as no2 was very awkward however tonight i thought sod it best check it and glad i did as this is what i found. Massively broken throughout. New plug ordered so i expect it to feel the dogs danglies once fitted.....be very interesting. I was getting a loud clicking from that area so i think it was the plug arcing. I think the garage that fitted it may have tried to do it with the loom and plug leads etc all in the way over no.2 cylinder or got impatient when trying to extract the socket over the plug as i know they can easily be broken with sideways movement.
 

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I use a long plug socket with internal magnet. It wasn't cheap but I've never broken a plug with this tool.

A quick way to check any of the FIRE engines is to point an IR thermometer at the exhaust stubs up against the cylinder head. Start from cold and keep checking the temperatures as they rise. The one(s) that heat slowest is/are suspect. Swap the coils and see if the cold spot(s) move.

It only works from cold, because a hot engine heats the whole manifold so they soon all look the same.

Further to the original question - 100HP has an electronic throttle pedal. Wear on the potentiometer tracks can also cause strange throttle effects.
 
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They say check the basics first and being lazy i only checked plugs 1 3 and 4 as no2 was very awkward however tonight i thought sod it best check it and glad i did as this is what i found. Massively broken throughout. New plug ordered so i expect it to feel the dogs danglies once fitted.....be very interesting. I was getting a loud clicking from that area so i think it was the plug arcing. I think the garage that fitted it may have tried to do it with the loom and plug leads etc all in the way over no.2 cylinder or got impatient when trying to extract the socket over the plug as i know they can easily be broken with sideways movement.
looks likely just changing this plug and the car will be running 100% fingers crossed
 
Yep got the new plug in tonight Denso XU22EPR-U.
Runs lovely now. EML light has gone out too
Amazing how a few pounds for one plug can make such a difference. The old had cracked on 2 sides.
Tomorrow she'll be getting an italian tune up.
 
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