1999 Dodge Dakota

[kb1gtt]

This a thread for a 1999 Dodge Dakota, V6 3.9L 4X4 with a history where several mechanics have failed to get it running. Frame and mechanicals are in decent condition, but ECU does not turn on fuel pump relay. It can run on starter fluid. This is in early days of OBD stuff. I've not found a reliable way to diagnose why the fuel pump is not activated. I got a replacement ECU from eBay with programmed VIN and mileage. That ECU turns on relay, but fuel pump or wire to fuel pump is bad. Parts on order, and it might start when I get these parts.

I plan to replace the ECU and do TCU control, using a Proteus v0.7 with F7. I plan to add WO2 and individual coils instead of distributor.

This first post will get updated as progress is made.

[kb1gtt]

The below is R0.1, beware IGNITION WARNING hazard. The ignitor is internal to the ECU, and this board does not properly isolate that voltage.

Breakout board pictures


Files found here https://github.com/jharvey/1999_Dodge_Dakota/tree/master/export/Breakout/V0.1

[kb1gtt]

I'm trying to draft a fuel tune. Currently VE is 60% across the board. Any suggestions on how to guess better VE values? It doesn't have a WO2 yet. I've got a 14point7 WO2 with sensor kicking around. I guess if I ignore the humidity issues, I could just clamp it to the outlet and that would get me at least kind of in the ball park.


Misc. notes are below

Per Rockauto, the injector is FJ683 then per the below page that's 158.55 g/min
https://www.injectorplanet.com/products/bosch-0280150998-chrysler-53031151

Per the below online calculator, I think the pulses at idle will be about 1.5ms and 16.3ms.
https://www.rbracing-rsr.com/calcinjpulse.html

Current tune found here
https://rusefi.com/online/view.php?msq=1536

Schematic found here
https://github.com/rusefi/rusefi_documentation/blob/master/OEM-Docs/Dodge/1999-dakota.pdf

Engine specs found here. https://www.engine-specs.net/chrysler/239-magnum.html
PDF copy for archive purposes here.

Chrysler 239 (3.9 L) Magnum V6 engine_ review and specs, service data.pdf

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