I am having a problem getting the injectors on my LS6 to pulse.

I thought it was the throttle position sensor but it is working OK.

I don't think it is VATs related as I have got a Baker Lim module putting out a signal for the VATs.

Does anyone know how I can test the crankshaft and camshaft sensors to see it they are working?

Any other ideas??

 

Are you using a GM PCM? I assume the car does not start. Make sure you verify the correct fuel pressure (55-60 psi at the fuel rail)? If the pressure is okay and based on your above comment I would lean toward the crankshaft position sensor (CPP).
With a GM PCM the engine will start as long as the CPP is operating properly.
An engine will start with a bad or shorted Camshaft Position Sensor (CMP), but will have extended cranking times if it is bad and cannot find the top dead center (TDC) on the correct stroke.

Either way a GM PCM will set codes (DTC's) if either sensor is bad or operating outside the preset parameters.

The VATS anti-theft system will shut off fuel to the engine if the PCM senses repeated improper start up. You need a scan tool to verify if it's "enabled" or disabled".

You need a digital multi-meter (DMM) to check the voltage for both sensors.
I don't have the GM manuals nearby, so I can give you a rough way to check them.

First, make sure you have the correct amount of voltage at the battery posts and secondary (AUX) positive battery connection.

* disconnect the PCM side connectors from the sensor.
* Turn the key (IGN) to the ON position
* With the DMM turned to DC connect connect the -NEG probe to a known good ground and connect the +POS probe to each of the female metal contacts in the PCM side connector. Do one at a time. You are supposed to get at least 12.00 volts to 2 of the three connectors. Honestly, I forgot which ones.
* Then take the +NEG probe from the DMM and connect to to one of the female metal contacts on the PCM side connector and take the +POS probe and connect it to the one of the other metal contacts (again, I forgot which one). It should also read 12.00 volts.

From what I remember both sensors require 12v to work properly and if little or no volts are present they will not work. Even though I don't remember what actual wires to test, you can "wing it" by probing each metal contact. You should see voltage.

I also assume you have a fuse circuit for the injectors; I would check for continuity to both sides of the female metal contacts where the fuse plugs into.

Post up if this doesn't help and I will go dig up my manuals for the exact procedure.

 

Thanks, great reply. I'll try thst and see what happens.

Paul