Earth spikes

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Liteace
TwoWaves
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Joined: Fri Jan 27, 2012 12:25 pm

Earth spikes

Post by Liteace »

Ive got here an old Fiat punto with an idle problem, I was having a probe about today, black was on battery negative and red was on engine earth (rocker cover) as you can see in the uploaded file there are a lot of spikes, are they there because the lowpass filter is not active ?

Thanks
punto earth 1.psdata
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Robski
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Location: Yorkshire

Re: Earth spikes

Post by Robski »

could well be interference from injection/ignition.

Whats the issue with idle ?

Liteace
TwoWaves
TwoWaves
Posts: 238
Joined: Fri Jan 27, 2012 12:25 pm

Re: Earth spikes

Post by Liteace »

The idle is to high and takes a long time to settle after a WOT, the temp sensor is faulty 1.6 volts @ 88c, should be 0.6v and the idle stepper is a bit sticky
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