Voltage spike

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orford2004
MegaSquirt Newbie
Posts: 33
Joined: Sun Jul 03, 2011 10:47 am

Voltage spike

Post by orford2004 »

When I run megalogviewer, I have voltage from 9V to 22V even with a brand new alternator. MS2 3.0

What can cause that?
Matt Cramer
Super Squirter
Posts: 2951
Joined: Sat Jul 03, 2004 11:35 am

Re: Voltage spike

Post by Matt Cramer »

Where is the MS2 grounded, and are you using low or high impedance injectors?
orford2004
MegaSquirt Newbie
Posts: 33
Joined: Sun Jul 03, 2011 10:47 am

Re: Voltage spike

Post by orford2004 »

Ms2 ground on the engine block and low impedance injector
Matt Cramer
Super Squirter
Posts: 2951
Joined: Sat Jul 03, 2004 11:35 am

Re: Voltage spike

Post by Matt Cramer »

Try this mod:

1. Cut the center leg on Q9 and Q12 or desolder it so it does not reach the PCB.
2. Run a length of jumper wire from the center leg of Q9 and Q12 to an unused pin on the DB37 connector.
3. Wire this pin to a 12 volt source in the wiring harness, separate from the Megasquirt's power supply wire.
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