2G CEL codes: P0300, P0170, P0125

[AdamWawrzyniak]

Need help getting ride of these codes and need some help figuring out what they are, and how can i fix them!!

CEL CODES: P0300, P0170, PO125

need help asap

 

[delta448]

P0300 Random Multiple Misfire

More than 1 cylinder is misfiring and the total number of misfires exceeds 20 misfires per 1000 engine revolutions.​

P0170 Fuel Trim Malfunction

Your ECU has adjusted the closed-loop fueling as much as it is able and the oxygen sensor is still showing it needs further adjustment. That means long term fuel trim is adjusted by 12.5% and short term fuel trim is adjusted by 10% in the same direction, whether they are both adding or subtracting fuel.​

P0125 Excessive Time to Enter Closed Loop Fuel Control

The front oxygen sensor has not switched around .5V for over 128 seconds while all requirements for closed loop have been met. The requirements for closed loop are:

• Coolant temp >= 180F
• Intake air temp < 133F
• Baro >= 22.9 inHg
• Baro <= 31.6 inHg

My advice is to check / replace the front O2 sensor, the fuel filter, the plugs and the plug wires. Make sure you have no exhaust leaks before the O2 sensor, make sure the FPR is not leaking, make sure the fuel lines are not kinked, make sure the O2 sensor wiring is not damaged, and purchase a datalogger.

 

[da_reeseboy]

Definitely start by getting a logger. It would be very beneficial to see what the o2 sensor is reading. How is the car running?

Based on the codes you posted and Delta's descriptions of those codes, the o2 sensor is not cycling past .5v, so you are running REALLY rich or REALLY lean. As a result the fuel trims have adjusted as much as possible to correct but its not enough. Misfires have become a side effect of this.

Possible causes:
1) failing o2 sensor(adjusting fuel trim based on a bad reading)
2) something wrong in the intake (maf sensor reading wrong, bad vac/boost leak allowing unmetered air into the system or allowing metered air to escape)
3) failure in fuel delivery (clogged fuel filter, fuel pump not moving enough fuel)

 

[AdamWawrzyniak]

I have never drove a turbo talon before, so i really dont no how it is running, i do no that i am getting very bad mpg than i should be getting!

Here is the picture of the o2's. I think the one wire for the sensor is cut. But there is another o2 sensor under it. Maybe the one that is cut is isent needed due to the one below it?

 

[delta448]

Definitely start by getting a logger. It would be very beneficial to see what the o2 sensor is reading. How is the car running?

It's probably reading low or no volts at all, which corresponds to lean signal to the ECU. The misfiring will make it worse, -if the sensor is connected and isn't dead-, since misfires send unburnt oxygen into the exhaust and make the sensor read even leaner.

Here is the picture of the o2's. I think the one wire for the sensor is cut. But there is another o2 sensor under it. Maybe the one that is cut is isent needed due to the one below it?

I can't see a second sensor in that picture and I don't see where the stock location sensor is even connected to the wiring harness. The wiring connector that the stock sensor plugs into should be under the water outlet.

Again, if you think there's a wideband somewhere that is simulating the narrowband signal to the ECU, a datalogger will confirm it much quicker than just tracing wiring.

 

[da_reeseboy]

If you are referring to the sensor on the top of the exhaust manifold as the sensor with the cut wire, that is an exhaust gas temp sensor. The one down by the alternator will be the stock o2 sensor.

@Delta: when you say the plug is by the water outlet, are you referring to the area on the passenger side, above the shifter cables on the transmission basically? Thats where mine is, but with all my car has gone thru it wouldn't surprise me if that was not the normal location .

@Adam: Follow the wire for the sensor by the alternator and let us know where it plugs in, as well as if its wires seem to be intact and undamaged.

 

[AdamWawrzyniak]

It goes to the left side of the car under the turbo and such, wire does seem in bad shape has rips and cuts in it.

 

[BigRed12]

It sounds like a bad primary O2 sensor.

The O2 sensor is showing that it is running VERY lean, so it is trying to dump more and more fuel in it, which will then cause VERY bad gas mileage and could cause your random misfire because its most likely not burning all of the fuel at one burn.

I would suggest replacing the primary O2 sensor. Thats what I would do anyways.

 

[carlos505]

The p0300 is a random misfire for sure, so that means it has to be at least two cylinders misfiring ,I had that code once it took awhile to find the problem. But might be easy for you so I would start with plugs. Hopefully your plugs are ngk if not that could be your problem I had Bosch and was misfiring once because of that also if you have platinum or iridium I would stick with platinum or copper but try to stay with copper if you can. Also check your gap make sure all gaps Are the same and are at spec, then check for wires check their ohms and continuity, than check your coils for primary and secondary circuits by checking their ohms and if worst comes then check your harnesses and wires all the way back to your ecu for any breaks or shorts, lastly check fuel injectors an o2 sensor could also cause that by running rich or lean, you can check their voltage as well .