Originally Posted by tony9385

99 Chevy Silverado, 4.3 vortec, Ive read a crap ton on hear, first time posting. Everything that I seem to research, including the Haynes manual say I shouldnt be able to start my truck with less then 50lbs of fuel pressure. Most I have gotten so far at one point was 42lbs and it will still start with 25lbs and still idle, rough but idle. All the grounds i have at least cleaned to shiny bare metal, new gas, new fuel pump, fuel filter, Fuel regulator and a MPFI. No matter how many times I turn the key now it wont go above 25-30 at best but still run? idol? no fuel pressure drop but def no gain. Actually seemed like the more grounds that I cleaned it got worse. Im getting .02-0.3 ohms in all places if checked the grounds. I guess ill start here.

Originally Posted by GeorgeLG

OK, it sounds like you are putting the meter inline from negative battery post to negative battery cable in dc amp mode. The confusion was because you have a digital multimeter that is capable of measuring volts (acting as a volt meter), amps (ammeter), resistance and depending on the meter possibly frequency, capacitance, etc.

The problem is that your "sleep" current (amp draw) is too high at 0.4 amps which is 400 milliamps. Ideally it should be under 50 milliamps and worst case it should be less than 120 milliamps. Make sure that you are really in sleep mode (wait 15 min), hood and doors closed and no lights on. If you still get 0.4 amps then open the drivers door, clamp the door switch, wait for sleep mode and then start pulling fuses to see where the draw is and then we go from there.

George

Originally Posted by csuperdock

Hey George, I did what you said and pulled fuse #19 RDO BAT and that is the one causing the draw, I've pulled that fuse out and now without that fuse I have no instrumentation on the dash, where do I go from here?

Originally Posted by GeorgeLG

There are four possibilities:

The radio is defective
The IPC is defective
An aftermarket device has been added to that circuit that is causing problems
There is a wiring problem

The easiest thing to check first is the radio. You will need to get it out of the dash and pull the connector to disrupt power and see if your problem goes away. Unless you know of a wiring hack/addition on that circuit then go there first.

George

Originally Posted by GeorgeLG

This now sounds like a passlock problem. This would be confirmed by having spark and fuel pressure but no injector pulses. Have you ever replaced the ignition switch, the passlock sensor or hacked the passlock resistor?


George

Originally Posted by GeorgeLG

There is more than one reason for the security light to be on but one of them is the passlock system failure. Have you ever had any codes associated with the security system? Passlock system is a module associated with the ignition switch that presents a unique resistor value to the PCM at start up to prevent the car from being hot wired. If the computer does not see the appropriate resistor value it turns off the fuel injectors after a few seconds. If that’s your problem then you need to either replace the Passlack module and perform a relearn, repair any wiring faults that are found, or perform a common resistor hack to bypass the issue. That last one removes the security feature and makes the vehicle easier to appropriate.

George