Throwing P0171 and P1170 codes

[B-R-Z]

Just tested the heater leads on the upstream sensor and I got no reading/resistance at all and I got around 6.5 on the downstream. I ordered a replacement Denso sensor.

[steve99]

Originally Posted by B-R-Z

Just tested the heater leads on the upstream sensor and I got no reading/resistance at all and I got around 6.5 on the downstream. I ordered a replacement Denso sensor.

sounds fairly convincing that the front sensor is no good. It unusual for them to fail, the likely cause is excessive torque when removong or installing sensor in header. Run a M18 by 1.5mm pitch thread tap\chaser through your header 02 bungs to clean up threads the sensor should screw in by hand then torque to correct torque. Put a very small amout of high temp antiseize on header threads, ensure you get no grease or antiseize on sensor tips.

[B-R-Z]

That's what I think too, I had to wail on a wrench with a hammer to get it off. I'm going to order or buy a o2 sensor socket.

[B-R-Z]

New Denso 234-9136 upstream (before cat) sensor




New vs old side by side comparison


New sensor installed

P0031 code gone!

[churchx]

Congrats on finding and fixing culprit

[avishenoy1]

Originally Posted by steve99

sounds fairly convincing that the front sensor is no good. It unusual for them to fail, the likely cause is excessive torque when removong or installing sensor in header. Run a M18 by 1.5mm pitch thread tap\chaser through your header 02 bungs to clean up threads the sensor should screw in by hand then torque to correct torque. Put a very small amout of high temp antiseize on header threads, ensure you get no grease or antiseize on sensor tips.

Hey so I recently installed the Vortech kit on my 2015 AT FR-S and have been having similar issues to yours. My tuner is Mike at Moto-East, and other than the supercharger I have the Openflash UEL header and Saikou Michi dual catch cans, both of which were on the car before the SC without any issues.

Shortly after starting the car up with the SC installed and the Ecutek reflash I threw a CEL and the car was idling rough and stalling at low rpms.

I've been getting the following codes in some combination ever since and have still not been able to fix the issue despite a couple tune revisions.

P2271 - O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 2
P0171 - System Too Lean Bank 1
P0172 - System Too Rich Bank 1
P2196 - O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 1
P117B - Direct Injector Fuel Performance Does not come on DTC
P1170 - Port Injector Fuel Performance Does not come on DTC

I've checked for vac leaks and have ruled them out by using soapy water. I also clamped all three evap hoses under the intake manifold.

I'm thinking it's an exhaust leak near the O2 sensor or a bad sensor.

[B-R-Z]

Could be, two of those codes contradict each other..too rich and too lean at the same time?

[steve99]

Originally Posted by avishenoy1

Hey so I recently installed the Vortech kit on my 2015 AT FR-S and have been having similar issues to yours. My tuner is Mike at Moto-East, and other than the supercharger I have the Openflash UEL header and Saikou Michi dual catch cans, both of which were on the car before the SC without any issues.

Shortly after starting the car up with the SC installed and the Ecutek reflash I threw a CEL and the car was idling rough and stalling at low rpms.

I've been getting the following codes in some combination ever since and have still not been able to fix the issue despite a couple tune revisions.

P2271 - O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 2
P0171 - System Too Lean Bank 1
P0172 - System Too Rich Bank 1
P2196 - O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 1
P117B - Direct Injector Fuel Performance Does not come on DTC
P1170 - Port Injector Fuel Performance Does not come on DTC

I've checked for vac leaks and have ruled them out by using soapy water. I also clamped all three evap hoses under the intake manifold.

I'm thinking it's an exhaust leak near the O2 sensor or a bad sensor.

getting all those codes at once it may be an electrical problem like missing or bad earths bad battery piunched shorted wiring due install

[avishenoy1]

Originally Posted by B-R-Z

Could be, two of those codes contradict each other..too rich and too lean at the same time?

Originally Posted by steve99

getting all those codes at once it may be an electrical problem like missing or bad earths bad battery piunched shorted wiring due install

I checked the battery and the engine ground cables and everything seems to be fine electrically. The car is a MY2015 with around 8600 miles on it and I'm not having any other electrical issues. I did install a wideband O2 sensor and spliced it into the Rear O2 sensor signal wire but the car was having the exact same issues before when the stock Rear O2 sensor was still on after the SC install.

I took a log this morning and the short term fuel trims were all over the place, maxing out positive at idle and dipping as low as -20% momentarily right when I release the throttle. I've attached screenshots of the log, the last one is zoomed in.

The fact that the Wideband (Custom Map O) and the Stock AFR sensor readings match up perfectly rules out a bad O2 sensor, so I'm thinking there may be an exhaust leak at or near one of the sensor bungs since both sensor's are reading full lean at idle? It could also be a vacuum leak but like I said I've checked every hose and clamp about 10 times.

Mike at Moto-East has already reduced the MAF scaling by 15% from the original tune and altered the hybrid speed density tables but that hasn't fixed it. Also the fact that it jumps from +35% to -20% seems to indicate a leak rather than a scaling issue but I'm not an expert.

Any input would be much appreciated.

Edit: Btw i'm running stock Fuel Pump and injectors, Omni 3 bar MAP, Openflash Header (Which was installed months before the SC with no CEL's or rough idle NA on Openflash stage 2 tune), Saikou Michi Dual catch cans (95% sure there's no vac leak from these since I removed them and still had the same problems, also sprayed all connections with soapy water), Clamped all 3 EVAP hoses under manifold, Vortech V3 with 3.48" pulley and Maxflow BOV (Also checked BOV vac line and adjusted spring so that it's closed at idle).

[steve99]

check all the plugs and bolts are fimly connected to tge Direct Injection computer under the bonnett, it gets it ground thruogh the mounting bolts and bracket.

[Dru670]

Originally Posted by avishenoy1

I checked the battery and the engine ground cables and everything seems to be fine electrically. The car is a MY2015 with around 8600 miles on it and I'm not having any other electrical issues. I did install a wideband O2 sensor and spliced it into the Rear O2 sensor signal wire but the car was having the exact same issues before when the stock Rear O2 sensor was still on after the SC install.

I took a log this morning and the short term fuel trims were all over the place, maxing out positive at idle and dipping as low as -20% momentarily right when I release the throttle. I've attached screenshots of the log, the last one is zoomed in.

The fact that the Wideband (Custom Map O) and the Stock AFR sensor readings match up perfectly rules out a bad O2 sensor, so I'm thinking there may be an exhaust leak at or near one of the sensor bungs since both sensor's are reading full lean at idle? It could also be a vacuum leak but like I said I've checked every hose and clamp about 10 times.

Mike at Moto-East has already reduced the MAF scaling by 15% from the original tune and altered the hybrid speed density tables but that hasn't fixed it. Also the fact that it jumps from +35% to -20% seems to indicate a leak rather than a scaling issue but I'm not an expert.

Any input would be much appreciated.

Edit: Btw i'm running stock Fuel Pump and injectors, Omni 3 bar MAP, Openflash Header (Which was installed months before the SC with no CEL's or rough idle NA on Openflash stage 2 tune), Saikou Michi Dual catch cans (95% sure there's no vac leak from these since I removed them and still had the same problems, also sprayed all connections with soapy water), Clamped all 3 EVAP hoses under manifold, Vortech V3 with 3.48" pulley and Maxflow BOV (Also checked BOV vac line and adjusted spring so that it's closed at idle).

Did you figure out what the problem was?

[B-R-Z]

Originally Posted by Dru670

Did you figure out what the problem was?

Replaced flex tubes in header with straight pipes. When removing the header i also noticed the bolts are a little loose which was contributing to the leaking; i had all kinds of gunk on the side of my engine block from exhaust flowing up the side from the loose header. In the process of removing the o2 sensors from the header i broke one of them which gave me codes after replacing flex tubes.

So after everything.. Tube replacement, header tightened and replaced o2 sensor, I had no codes