2012 Mitsubishi Outlander Running Rough/Stalling Issues

So, This has been a hell vehicle if I've ever seen one.

2012 Mitsubishi Outlander 3.0L V6 S-AWC

Original complaint was the vehicle would die shortly after a cold start, but after 2-3 minutes it would restart and drive perfectly fine.

Codes showing were:
P0051 | Oxygen Sensor / Linear Air Fuel Ratio Sensor Heater Control Circuit Low (Bank 2 Sensor 1) - Stored DTC
P0431 | Warm Up Catalyst Efficiency Below Threshold (Bank 2) - Stored DTC

Customer had been driving with the P0431 for a while not wanting to shell out money for the cat at that time, so the new code was heater control circuit low.

Original thought was possibly a fuel restriction caused by debris in the fuel tank (I've seen a few of these rusted inside the tank and clogging the internal filter.) Pull the pump, looks great inside. No clogging or fuel pressure issues.

Customer takes vehicle back and it runs fine for the week. Comes back with same complaint. Wasn't able to verify the complaint until I got permission to take the vehicle home to try to replicate. Runs beautifully for my 45 minute commute home. Restart in the morning, make it 3 blocks and vehicle dies and wont restart. Only data I see is that the injector pulse width gets to 14ms as it shut off. No crank or cam signal missing as it dies.

It restarts and drive the rest of the way to work without issue. I finally get it to act up while scanning at work and try to disable injectors, 2 injectors out of 6 don't change the RPM at all, I am suspecting injectors. So I pull the injector relay and put a relay bypass switch with current loop in and scope the injectors. Come to find that one of them (I didn't have a sync lead connected so I am not sure which one exactly) is shorted, pulling 0.9 amp at all times, but I can see the other 5 still firing (they are just pulling up to 1.9amps now because of the one shorted) I am thinking computer or wiring (computer transistor stuck on, or wiring shorted out) Inspect the wiring and don't see anything shorted to the injectors, So my boss decides to call a computer instead of pulling the manifold and shelling out $200 an injector when I can get a used computer for $150. We do that, now I have no more shorted injector problem, but every once in a while I have 4 injectors not even pulling amperage, just 2 pulses on the scope before it stalls out.

I found injectors aftermarket for $250 for the set, and install those thinking these are a possibility as well (Customer wanted me to throw plugs at it anyway (due for mileage, upper intake must come off for the plugs so I did injectors as well while I was in there) Still doesn't fix it.

Boss says order another computer, because it is showing different failures now. So we do, now I have a reading of 0v on my B1S1 after it runs for a couple minutes.

My issue is I have had a different failure with 3 different computers. Original showing 1 shorted injector. Second computer having 4 injectors not pull amperage at all, but no codes present and the 3rd computer now showing a P0300 and having the voltage go to 0V on that o2 sensor.

I am really stumped. I have checked cam signal, crank signal, MAF, MAP, and replaced injectors and spark plugs.


Any advice? I can pull scan data or scope captures if anyone thinks that would help.

Thank you in advance.

Are the replacement computers used or new?

With the 3rd computer all i (new?) njectors draw the same amount of current?

Does the O2 correspond to forced enrichment/enleanment?

Interested in the mentioned scan and scope data...

Replacement computers are all used.

Injectors are new.
Injectors all draw same amount of current, no shorting anymore.

I didn't think to force enrichen the mixture because after it stays at zero volts for a minute or so it does return.

What would you like a scan/scope measurement of? I only have the snap on Triton D8 so I can only do 2 channels at a time, but I have captures of the injectors running fine now, and when I had a shorted injector and when I had 2/6 cylinders firing previously. Any time I have checked these I try to have a CKP or CMP reading, and every time I have done that it has been fine. (I am not able to verify timing as I don't have a known good, but the signal is nice and clear.

I'd be interested in O2 data versus injector on time, especially when the sensor is going lean and when it recovers, additionally fuel trims with reported mass airflow. Scan data will just be fine if it is viewable in Shopstream.

Secondary scope captures under the same conditions maybe helpful too.

The mentioned misfire is not reported on mode 6 data neither?

Last, not least: are you positive the injectors have the correct flow rate?

The link shows the CKP/CMP reference:
rotkee.com/en/wavebase/good-timing-ckp-c...3&system=51&subsyste m=73

I only know that the injectors were listed as aftermarket replacements.

The scope capture is a sync pulse from #2 injector, and a low amp clamp, set on 100mV/amp. on the injector relay

Here is a scandata capture of a stall