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Lifter Pin backed itself out so I had a fun time fixing that. Got everything back together and she fired up first try. Now a P0200 code is throwing. I know the common chokepoint at the fuel rail but I have an LS3 without that fuel rail support so it isn't that.
Thought maybe it was one of the ground signal wires going to the ECU but I checked those while thrashing around the harness and they all seemed fine. That's when I realized the log is showing it was going lean intermittently, meaning the short must be on the hot side, right? If it was shorting on the switch side it'd be spiking rich
Does this look like one injector or the whole bank 1 injectors? Idle is off, afr's are bouncing, I'm guessing it's because of this shorting issue.
I’d have to check the code setting criteria for a P0200 but I’m sure the PCM is only monitoring the control side of the injector circuit…are you seeing misfires ??…if you disconnect an injector harness and run the engine while having a 12 volt test light connected to battery positive does the test light blink, is it on constantly on or not blinking at all while probing the control wire(striped wire) ??…can’t open your log but are your long term fuel trims positive or negative ??…if the control side wire was shorted to ground or the PCM driver were stuck closed the engine would run VERY rich and trims would be very negative. If this is an intermittent condition having a lab scope is the best way to diagnose this…every time there is that intermittent condition you’ll see it !!…in the scope capture below the red is #1 injector firing and the smaller blue trace is injector current (taller ones are the coil ramps) for all 8 cylinders…I can increase the time base to see many injector coil ramps and see when the current drops out…that would be the bad injector…each injector pulls around 1.2 amps…going to move this thread to Tech !!
Here is the look of the logfile
And the DTC P0200 description below
I guess one or more injectors may get get shorted in the coil and the PCM does not receive proper voltage through the coil(s)
Try to measure coil resistance on all injectors when your engine is cold and when the engine is hot and check for differences .
They should all be similar in the area of 11-16 ohms
Here is the look of the logfile
And the DTC P0200 description below
I guess one or more injectors may get get shorted in the coil and the PCM does not receive proper voltage through the coil(s)
Try to measure coil resistance on all injectors when your engine is cold and when the engine is hot and check for differences .
They should all be similar in the area of 11-16 ohms
By coils are you referring to the coil packs or coils as in the ground control on the injectors? Low resistance would mean that there's a short? I cut little slits in the main coil pack harness before it splits into the 4 coils, could that cause the P0200?
Also, I tore everything apart again to check if any wires had damage. From what I saw from the PCM to the injectors the wires (the parts that are exposed) all looked solid. I did a continuity check for all injectors and they seemed good, twisting the harness to try and get a short. How do I go about testing the resistance of the coil?
The symptoms changed as well after I got everything back together. Here's the new log
Wouldn't a P0200 still trigger if there was a hot side short? Wouldn't the voltage be 0 when the circuit is grounded which is the same as a ground short?
Wouldn't a P0200 still trigger if there was a hot side short? Wouldn't the voltage be 0 when the circuit is grounded which is the same as a ground short?
What pin is the power supply from the PCM?
Power for the injectors comes from the battery through Ignition Relay 42 then through a fuse…does not come from the PCM !!
P0200 From Hot Side Short (I think)
