View Full Version : What causes inj duty to drop?

11-30-2014, 07:37 PM
On a stock ecu what parameters causes injector duty to drop from roughly 57% to 8%?

Maf voltage?

11-30-2014, 08:33 PM
Most common is actually the voltage supply because they work in a fairly small window. Check your batter, grounds, and the wiring to the injectors before you go too far into it.

11-30-2014, 08:37 PM
Injectors work with a constant 12v and a ground signal that is very important that drives the injector. It's the ground that tell the ECU how much to spray. That is why people say don't solder because stuff like this requires precise voltage/signal. Introduction of more resistence can throw things way out of wack.

11-30-2014, 09:42 PM
Thanks for the inputs guys. It was maf voltage. Whats weird is the maf curve (used for maf simulation to go mafless) i used for the 5857 was completely different with the one that worked for the hx35.

The ecu was pulling inj duty. All injectors individually at different points.