My Dyno day got screwed. The day before I'm to start my journey I get this check engine light. I spent 12 hours trying to figure it out! We did a smoke intake leak test, checked for exhaust leaks. I'm stumped. All I had did was change the spark plugs to a heat ranger warmer from 7s to 6s. Light came on I deleted it within a block it came on again. Checked for vacuum leaks a block later came in again. Did the leak tests ect. Now the code doesn't throw the light but it does show in the computer as pending. Then moves to "failed since clear" status in my scanner whatever that means. It's the only code in there. 2 of the 3 times it came on was at idle and the other time was at 1400rpms likely when slowing down according to the freeze data..... I'm starting to think the code has been in there pending a while. I did upgrade to the torqhead 24x system 2 weeks ago.......Thoughts?

 

Look for vacuume leaks and exhaust system leaks. Unmetered O2 is getting into the engine from somewhere on Bank 2. Could be any number of places for a leak such as fuel injector o-ring, PCV leaks, intake and exhaust manifold leaks. Use of starting fluid or brake clean while the engine is running might help you isolate where the problem is.

 

Headers? Bank 2 means it's on the passenger side. Could be as simple as an exhaust leak or faulty O2.

https://www.fixdapp.com/blog/p0174-code/

 

I swapped o2 sensors to oppiset side today same code

 

If it follows the o2, get some live data on the voltage readings while running in CL? If I recall correctly a lean condition will cause voltage to drop. Im not electrical savvy in any way tho.

 

Still trying to chase this down. I swapped all injectors, ow sensor, coil packs and wires to the opposite side. I put a Shop-Vac in the tail pipe and sprayed soap water all over the headers, I did an intake smoke test. I even got hptuners to see things and sure enoight the computer is still seeing lean on bank 2 and adding 25% more fuel. But it's only at idle. I also sprayed every vacuum line I could find on the intake with break cleaner and nothing. I'm going. Crazy. I missed my 3 month wait on getting this tuned on a Dyno finally and now this. Ugh!!!!!!! I'm stumped!