2001 SX225 Ox66 Sensor voltage

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Did some old fashioned testing yesterday and found that #3 cylinder is not acting like the others not counting #2&#5 (I hope theses are the two that stop firing below 1800 RPM)
I had it running and pulled the plug wires one at a time and found that #3 just barely changes when the wire is pulled, the others are very noticable when pulled and put back on so I swapped the coils and injectors with a one of the cylinders that seem to be firing strong and it made no change.
Also did a half assed spark jump test with a piece of brass rod in the plug boot and all the cylinders would jump about 3/4" inch.

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Up for another try

[jb123]

did you replace the lp pumps with OEM or sierra ??

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Only use Yamaha parts, so how do we rule out the ECU?

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Any Ideas?

[Tucker]

Just re-read the thread and don't see anything about you testing the spark plug caps. You have resistior caps and they should measure at about 5-6 ohms. Just had 5 that were out of spec on my motors. There is a comon misconception that these are strickly for radio interference; but the rodbolt said if they're out of spec performance will be off.

[Inpursuit]

Just re-read the thread and don't see anything about you testing the spark plug caps. You have resistior caps and they should measure at about 5-6 ohms. Just had 5 that were out of spec on my motors. There is a comon misconception that these are strickly for radio interference; but the rodbolt said if they're out of spec performance will be off.

Yep checked them and they are all within spec

[Tucker]

Checked Pulsar coils? Need to work backwards if no spark.

[Inpursuit]

Checked Pulsar coils? Need to work backwards if no spark.

I have spark just not very strong on the one cylinder

[rodbolt17]

then using a peak reading meter or a DVA adapter check cdi output voltage.
cap resistance should be in the 6K ohm range.
a bit different than 5 ohms.

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Check the CDI output voltage to the coils?, what kind of voltage numbers are we looking for?
I checked the plug caps and they are in spec to the manual @ 4.35K - 4.65K but you say they need to be closer to 6K
I still would like to know about the 5V ref. voltage being low coming out of the CDI, I unhooked everything from it and it's still low.
Pulser coil ohms out at 346-350 for the 6 terminals.
Please explain exactly how to check CDI output voltage.

Rodbolt let it be known that I greatly appreciate you're knowledge and help.

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[99yam40]

Do you have the service manual for your motor?
It gives the step by step procedure on troubleshooting the system.

Do you have the DVA adapter to take the readings with?
or a peak volt meter made for these motors?
A regular voltmeter will need the DVA

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Yes I have the Yamaha Manual but i'm a machinist not an electrician but am trying to learn.
I don't think I have the right meter so a new one will have to be bought.

[99yam40]

The DVA adapter will be cheaper