Starter sucks up too much voltage, can't datalog during cranking

GM PN# 89017847
AC Delco PN# 323 1640 A22

If I understand correctly this is the "truck starter" lots of folks prefer for LS3 applications.

I have an LS3 crate engine with a cam that isn't outrageous, but not stock. Space for the starter is a MAJOR constraint. This starter is absolutely at the limit of what can fit.

Is there an option someone can recommend for a starter that can handle a stock compression ratio LS3 while being less demanding in terms of voltage and space?

I am also going to approach this issue from the battery-strength side of the equation as well. Current battery is an Odyssey PC925 (AGM).

Either there's a fault with your particular example of that starter (not a problem with that part number itself), or, you have a voltage drop issue (more likely). If you don't know how to test voltage drop under load, go look it up.

Of course this advice is based on only what you've provided, which is nothing but a story about this thing that happens. No data. You've heard of 'GIGO' I assume.

...or maybe your DLC pin 16 is powered by an IGN feed that is hot in RUN but not CRANK. Nobody knows what you're working with here, a swap vehicle with non-stock wiring or an as-built factory something.

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Originally Posted by blindsquirrel

...or maybe your DLC pin 16 is powered by an IGN feed that is hot in RUN but not CRANK. Nobody knows what you're working with here, a swap vehicle with non-stock wiring or an as-built factory something.

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Here would be a quick test to give a yes/no on the 'starter sucks up too much voltage' hypothesis: Disconnect the trigger wire from the starter solenoid. Start the scanner. Turn key to CRANK. Does the scanner still drop out?

Other very very basic Electrical 101 things to check: What is the voltage at the battery +/- terminals while the starter is cranking the engine? What is the voltage between starter B+ post/ground while cranking? What is the voltage at DLC #16 while cranking? Those will give you a direction on where to concentrate with deeper checks like voltage drop on specific circuits.

If voltage falls off a cliff when going direct to battery +/- then that's a battery issue. If it's OK at the battery but not at the starter that's a B+ cable or ground cable issue. If voltage is good at the battery and good at the starter but not at the DLC than that's an ignition switch/wiring config issue.

Judging by some of his other post, this is a swap vehicle.

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Originally Posted by blindsquirrel

...or maybe your DLC pin 16 is powered by an IGN feed that is hot in RUN but not CRANK. Nobody knows what you're working with here, a swap vehicle with non-stock wiring or an as-built factory something.

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very common mistake on hotrods.

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Originally Posted by TransGo Robert

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Oh shit Robert got him a crystal ball y'all LOL

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Originally Posted by edcmat-l1

Oh shit Robert got him a crystal ball y'all LOL

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:p