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Posted by: gifted914 Apr 17 2013, 09:19 PM

G'day all.
Does anyone know the operating voltage and amps on the injector.
I dont't thing it is straight 12 volts.

Peter

Posted by: kg6dxn Apr 17 2013, 09:30 PM

It is a 12V injector. The amperage is in the mili amp range. Measure the resistance and use Ohm's Law to solve for current.

Posted by: Dave_Darling Apr 17 2013, 10:43 PM

The 1.8s have the resistor pack which drops the voltage going to the injectors.

The 1.7 and 2.0 ECUs do not supply 12V, either.

Hmm, actually: according to the D-jet bible, the D-jet injectors see a peak of just over 12V, and are held open by 4-5V.

http://members.rennlist.com/pbanders/ecu.htm#D1-D2

--DD

Posted by: gifted914 Apr 18 2013, 01:13 AM

thanks

Posted by: gifted914 Apr 18 2013, 01:13 AM

Thanks

Posted by: sofi2t81 Apr 18 2013, 08:48 AM

I talked with a Bosch guy at the Techno Classica in Essen (Germany) who gave a short presentation about the D-Jet.

The Voltage from the ECU is 3V!

Peter

Posted by: gifted914 Apr 18 2013, 03:53 PM

Thanks for the info.

Peter

Posted by: Spoke Apr 18 2013, 06:07 PM

Keep in mind that the 3V is output only when loaded with the injector. If one were to disconnect the injector, the output is actually 12V.

There is a resistor between the switched 12V and the output. The resistor is about 6 ohms (6.15 ohms in P Anders website). The resistor limits the current through the injector and the voltage across the injector.

The injector resistance is 2.67 ohms in P Anders website.

One calculates the voltage across the injector to be a resistor divider between the internal 6.15 ohms and 2.67 ohm injector.

So with the injector, the measured voltage would be : 12V x 2.67 / (2.67 + 6.15) = 3.6V.

The injector current would be limited by the injector and internal resistances: 12V/(2.67 + 6.15) = 1.36 Amperes

If you want to test an injector, use 12V with 6 ohms in series with the injector.

The 6 ohm resistor does have to be a power type. Power calculated by I x I x R = 1.36A X 1.36A X 6 = 11 Watts. A 5W resistor would do since one would be pulsing the injector on and off to test (assumption).

Sorry to get so technical.