Voltage spikes.

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trakkies
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Voltage spikes.

Post by trakkies »

I've just fitted some new heads and injectors to my Rover V-8, so have been doing some tuning tweaks on MS. It's an MS2 V3 running the latest B&G code. After logging and viewing, I noticed some strange voltage spikes, both above and below the 13.8v norm. Max 21.8v, min 7v. They don't seem to coincide with any abnormal readings elsewhere so do I just ignore them?
Dave P, London UK.
Rover V-8
MSII V3
EDIS
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Matt Cramer
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Re: Voltage spikes.

Post by Matt Cramer »

Where is the MS grounded?

Are you running high or low impedance injectors?
trakkies
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Re: Voltage spikes.

Post by trakkies »

Matt Cramer wrote:Where is the MS grounded?

Are you running high or low impedance injectors?
Low impedance - the ones as used by the original Lucas injection with resistors. I'm not using the resistors.
Dave P, London UK.
Rover V-8
MSII V3
EDIS
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Matt Cramer
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Re: Voltage spikes.

Post by Matt Cramer »

Might want to try using the resistors. This can make for a little less noise.
trakkies
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Re: Voltage spikes.

Post by trakkies »

Just wondering why go to the bother of designing MS to drive low impedance injectors directly if it's just as good to use resistors? I made my new loom excluding the resistor pack. After reading the benefits of driving them directly on this site. :(
Dave P, London UK.
Rover V-8
MSII V3
EDIS
Tech Edge Wideband
kredden
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Re: Voltage spikes.

Post by kredden »

I'm seeing the same thing in my Alfa with low impedance injectors. What does "using the injectors" mean? Steps 69 & 70 of the V3 assembly steps? I did both of those and I've got my grounds going to the engine block and set up like the DIYAutoTune article (http://www.DIYAutoTune.com/tech_articles/grounds.html).

Kevin
kredden
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Re: Voltage spikes.

Post by kredden »

kredden wrote:I'm seeing the same thing in my Alfa with low impedance injectors. What does "using the injectors" mean? Steps 69 & 70 of the V3 assembly steps? I did both of those and I've got my grounds going to the engine block and set up like the DIYAutoTune article (http://www.DIYAutoTune.com/tech_articles/grounds.html).

Kevin

Sorry, meant "using the resisters" not injectors!

Kevin
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