Solved! No spark at 3000rpm after msd crank trigger installation

#1 · July 23, 2024, 3:03 pm

Quote from Jonas on July 23, 2024, 3:03 pm
Hi all,

My fitech 600 power adder run fine until i installed a msd crank trigger. Before i used the signal from my msd distributor.

At around 3000 rpm it sounds like it is in a rev limiter.

Rpm limits are all set correctly and 2step control is off. Rpm readings are correctly in the Handheld. No error codes.

Any idea what to look at? Thank you very much.

Here is the fix:

it turns out that on msd crank trigger it is imporant that the two wires from the pickup are connected correctly.

I found this post on the internet:

"Polarity of the green and violet wires on the crank trigger sensor will likely affect your timing. MSD advises that the correct polarity is the one that has the most timing advance on a Digital Ignition. For analog ignitions, this is opposite, and the correct polarity is the one that has the most retard. Do not assume that just because the violet wire is connected to the violet wire that the polarity is correct, you must try both polarities to see which one generates the most advanced setting on a digital ignition (or most retard on analog ignition)."

first thing i did i used a timing light an rev the engine up to roughly 3000rpm were it behaved like a missfire. The timing light showed 40+ advanced ignition timing while the fitech handeld showed normal 30+ timing.

I then switched wires on the crank pickup. Before, the timing light showed exactly 20° advance when i lock the timing ar 20° in the Fitech Handheld. After the wire change, the Timing light showed 10° on the balancer while the timing was locked at 20°.

I was a bit confused, because in the statement above it says " MSD advises that the correct polarity is the one that has the most timing advance on a Digital Ignition ".

However, with the more retarded timing after the wire change i was able to rev the engine up fine. I set the timing correctly to match the numbers in the handheld and now the car is driving fine again 🙂

Can anyone explain, why the fitech likes the more retarded timting for "analog ignition systems" and missfires on the setting for digital?

Hi all,

My fitech 600 power adder run fine until i installed a msd crank trigger. Before i used the signal from my msd distributor.

At around 3000 rpm it sounds like it is in a rev limiter.

Rpm limits are all set correctly and 2step control is off. Rpm readings are correctly in the Handheld. No error codes.

Any idea what to look at? Thank you very much.

Here is the fix:

it turns out that on msd crank trigger it is imporant that the two wires from the pickup are connected correctly.

I found this post on the internet:

"Polarity of the green and violet wires on the crank trigger sensor will likely affect your timing. MSD advises that the correct polarity is the one that has the most timing advance on a Digital Ignition. For analog ignitions, this is opposite, and the correct polarity is the one that has the most retard. Do not assume that just because the violet wire is connected to the violet wire that the polarity is correct, you must try both polarities to see which one generates the most advanced setting on a digital ignition (or most retard on analog ignition)."

first thing i did i used a timing light an rev the engine up to roughly 3000rpm were it behaved like a missfire. The timing light showed 40+ advanced ignition timing while the fitech handeld showed normal 30+ timing.

I then switched wires on the crank pickup. Before, the timing light showed exactly 20° advance when i lock the timing ar 20° in the Fitech Handheld. After the wire change, the Timing light showed 10° on the balancer while the timing was locked at 20°.

I was a bit confused, because in the statement above it says " MSD advises that the correct polarity is the one that has the most timing advance on a Digital Ignition ".

However, with the more retarded timing after the wire change i was able to rev the engine up fine. I set the timing correctly to match the numbers in the handheld and now the car is driving fine again 🙂

Can anyone explain, why the fitech likes the more retarded timting for "analog ignition systems" and missfires on the setting for digital?

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Solved! No spark at 3000rpm after msd crank trigger installation