So, in chasing the random misfire codes I found the hose from the IACV to the intake came loose from the severe angle it was at, I need to get a thinner more flexible hose so it is not pushing on the coil pack wire. But I cranked it down and it is holding.

I had a 0301 misfire code for the same cylinder, #1. Swapped spark plug, no change, swapped plug wires the misfire code went away. They were new ACDELCO wires, so I am sure I can get a new one. With the fuel injector failure message, one post on here said not to drive it, that it was open and blowing fuel into the cylinder. There are no other symptoms or codes, as one would expect if it were truly running rich.

I had bought Chinese fuel injectors, so maybe this one is bad. Before I pull off the intake to replace it with one of the old ones. Is there anything else I should I try? The plug connection looks tight, the injector looks seated properly.

Thanks for the thoughts.

 

Everything I’ve read about Chinese Injectors is that they’re very prone to failure. Getting your stock injectors cleaned and tested costs twice as much as a new set of Chinese injectors, but seem to have a very high chance of working long term.

 

Put a mechanic's stethoscope (or long screwdriver) on the injector to listen if it is firing properly. Easy to hear at idle. Compare sound with other injectors. Other option connect a 9V battery to the injector and listen for a click (in a quiet place) when connecting and disconnecting.

The way I read code P0201 is the electrical circuit is open, meaning loose connection or broken wire (or rarely failed ECM). Not that the fuel path is open. Either way, should run rough if the code is active. Monitor O2 sensor voltages (upstream) to see if system is functioning well, and check fuel trims to see if both banks are nearly balanced.

By the way, if you swapped a bad wire, the miss should follow the wire, otherwise it maybe was not connected securely.

 

I did the below, good suggestion. The #1 injector is not clicking, to confirm the noise, I tried #5 and could hear the rhythmic clicking. I also put 12v on a few of the old fuel injectors, you can hear them click as one would expect. Does that mean the injector is likely bad?

I need a battery for my multimeter to test the coil pack, which is new, All Makes, if that matters. I can test that later today.

I am hoping that I can just undo the 4 bolts holding the intake and carefully pry it up enough to get access to the fuel injector.

Interestingly on closer inspection, several of the old ones are missing the hard plastic retaining ring. They must of fallen into the cylinder at some point in their life and burned up.

I am also getting a P1668 code, as a potential error, flashing SES light. Which appears to be either a generic misfire code or an antitheft immobilizing code.

Per Torque, the O2 sensors are working, mostly, or at least intermittently, seems like sometimes the graph does not change, I assume that is an anomaly.

I tried to set up the Fuel Trim for each cylinder, but it looks like either Torque or the ELM does not communicate that info. Might need the Fusion app? Or, maybe that is not relevant to my issue.

 

So, #1 not ticking could mean the wiring or connector is bad, or the injector is bad. Test the #1 injector with 9V (or 12) and listen for a faint click. Or plug a known good injector onto the #1 harness and see if it ticks with the engine running.

I get fuel trim data on Torque, but sometimes more than one option, so need to pick the ones that show numbers (data) in the menu list.

 

Agreed with most of the above, swap known good with known bad.

 

I took a couple of the old ones, cleaned them, ran 12 v and they ticked audibly when they got power. I just pull the "new" one, the first time I powered it, it did not do anything, then I shorted it my accident and started clicking loudly. Which leaves me to think it was stuck or otherwise not operating. I went and put one the tested good ones, the originals in. It seemed like a better bet than swapping with an adjacent injector just to put it all back together and have the problem follow the injector.

Question is how much do I need to put back together to get power to the injectors so I can test if the wiring is bad? Can I just put the key in 2 and test for power at the wiring harness? Seems like a bad idea to start the engine w the intake apart.

 

Maybe just put it all back together now. The wiring can be tested after that, or just run the engine to see if code clears. The throttle needs to be installed to run the engine. Or do the voltage test you mention. The ECM actually switches ground to activate the injectors, so that part of the circuit is a bit more involved to test, but do-able.

I had a bad injector that acted that way before, got stuck sometimes.

 

I would return the new one. If its acting odd now, I don't think it would get better. On the LR3 I had a funky injector that wouldn't always fire due to extra resistance within the relay. Swapped it out with a new one and haven't had a problem since.

 

So far, knock on wood, this seems to have fixed it. Will put some more miles on it and go from there. Put the original fuel injector in.
Thanks to everyone for the ideas.
For reference, this was the defective injector.