LC1 and Lean AFR Reading

[Oldsid]

I finally installed my LC1 with the gauge and all went well. I did the final free air calibrations and then warmed the car and took it for a test drive. At a steady 80Km/hr, my gauge display fluctuate between 16 to 16.2 AFR. Since it is at cruise, the ECU is in closed loop, should it not display around 14.7? I also noticed that most of the time, the AFR is around 16 to 17 which is way too lean. I checked my gauge reading to LogWorks values and they perfectly match. I am planning to redo the free air calibration again and check for exhaust leaks and would like to know if there is anything else I should do to find why the AFR reading is so high.

 

[tenn-gsx]

Mine does the EXACT same thing!

 

[Oldsid]

I forgot to mention that during hard accelaration and boost (stock), the AFR reading is between 10 and 12 . I am about to install my ECMLink V3 and use the the wideband to simulate a narrow band but wanted to make sure that the LC1 is OK. Could the problem be caused by my stock narrowband?

 

[Oldsid]

I don't seem to have any exhaust leaks and after another free air calibration, it is still the same. Now the gauge get stuck on max lean and it is the same on LogWorks. Anyone out there with any ideas?

 

[tenn-gsx]

Again......... Same stuff outa mine. I never figured it out after 1.5-2 years and i am onsidering just going to an AEM unit.

 

[Oldsid]

Again......... Same stuff outa mine. I never figured it out after 1.5-2 years and i am onsidering just going to an AEM unit.

I talked to Innovate support and I was told to check if the Bosh sensor is good. They suggested that I put it at the exhaust pipe of another car and see if it reads correctly at idle. I will try that somtimes this week and see if the snesor is defective. If I can make it work, I will probably get another one for another vendor.

 

[LiquidX]

1. Where is the o2 sensor positioned?
2. Redo the free air calibration
3. Verify no exhaust leaks


When you go WOT your reading should actually be in the low 9:1 AFR and people strive to get 11.3:1 AFR on WOT.

Do you have the stock MAS still? If you are going to run narrow band simulation get that hooked up and check the numbers again. If you have the sensor post flex pipe, that could be your issue.

 

[tenn-gsx]

How would the flex pipe cause this? Not saying it cant. Im really asking.

 

[LiquidX]

The flex pipe isn't solid pipe and can be prone to leaks which is why it's recommended to place the sensor pre flex pipe and as close to the turbo as possible.

 

[Oldsid]

1. Where is the o2 sensor positioned?
2. Redo the free air calibration
3. Verify no exhaust leaks


When you go WOT your reading should actually be in the low 9:1 AFR and people strive to get 11.3:1 AFR on WOT.


Do you have the stock MAS still? If you are going to run narrow band simulation get that hooked up and check the numbers again. If you have the sensor post flex pipe, that could be your issue.

I re-did the free air calibration and I checked the exhaust manifold, the O2 housing, the turbo and the DP and there is no apparent sign of leakage. The O2 sensor is about 12" down of the O2 housing but before the Flex.
I still have the stock MAS but don't understand what you mean by "hook up and check the numbers again". I also mentionned in my last post that after I redid the free air calibration, the readings are all over 22 on LogWorks and the gauge is stuck at maximum reading.
Is there a more reliable way of checking for exhaust leaks beside looking and checking visually of for loose bolts? What else could cause such a high reading besides exhaust leaks? I read in this forum something about the software version but I have not checked that yet. What is the minimum voltage that the LC1 needs to work properly? How can I test the sensor?
I will be searching some more and see if there is something out there that can help.

 

[sbiggi]

Redo the heater calibration too.

 

[streetdsmpwr]

I just got my LC1 in Sunday and it works great. I have my wideband sensor in the second O2 position in my exhaust after the flex and after were the cat should be. It reads fluctuates around 14.7 at idle and off boost. You sure its not a bad ground or wiring problem? Like the others said it may be an exhaust leak. I'm not a wiz with this stuff by any means.

 

[Oldsid]

I have finally resolved the issue of the reading of my AFR at cruise (closed loop)
Here is an overview of what I did :

1) I rechecked my wiring as per LC1 installation manual and made sure everything is correctly wired.
2) I checked for exhaust leaks. Besides a visual inspection, I used a incense stick to generate smoke and passed along the the exhaust manifold gasket, turbo to manifold flange, and O2 housing to turbo/DP gaskets. The smoke did not seem disturbed so I assumed there was no leak. I did tighened the DP to O2 housing studs to the torque value of the stock downpipe before I did the test.
3)I redid a free air calibration and test the reading of the gauge and through Logworks but there was no change. The reading were still around 16 at idle and 15.6 to 16 at cruise as mentionned at the begining of this thread.
4)I tested the Bosch sensor by removing it form my DP and putting it in the tailpipe of the van. I used a locking plier making sure that it is just tight enough to hold in place. I did cover all non metal parts with aluminium foil to avoid damage to the wires and their heat shield. The sensor needs to be completly inserted in the tailpipe otherwise it may be contaminated by outside air and give innacurate readings. The AFR reading of the van was a perfect 14.6 to 14.8 at idle. This eliminated the sensor as a possible cause.
5) The only thing left to me was the possibility of the stock sensor causing the lean offset. I had a NTK stock replacement O2 sensor so I installed it and checked the car a idle. The reading was still between 15.4 to 16 with the car completly warmed up. I took the car for a road test and guess what! the reading at cruise is steady between 14.4 to 14.8. A log with LogWork shows an average of 14.5 at cruise. Now, and once the car is warmed up, the idle AFR is also the same as at cruise and everything seems to be good.

From all the tests I have done, I can at least say that the LC1 is reading correctly and that my old O2 narrowband was probably causing the offsett at cruise. I can at least install ECMlink V3 and know that my AFR readings are correct and the LC1 is working as it should. I think that a 0.2 offset at cruise could be due to a small leak in the intake. I am still at stock boost with stock boost control solenoid and the boost is steady at around 14 PSI on a Greedy boost gauge. I will do a boost leak later and fix an leaks and retest to see if it will correct the small 0.2 offset in the AFR at cruise.