Please don't clog this thread with stuff like "how do you supercharge your 2.4"

Background: S/C the 2.4 in 2007? Put about 60k boosted miles on it. Stock pulley, cobra h/e, LFR6A-11 copper plugs @ .034

Symptoms:
- Especially when the a/c is on, idle bounces around upon taking it out of gear (off load) and coasting to a stop
- Misfires most between 40-50mph under light load
- extreme KR >3deg greater than 3800 when more than 50% load

Compression test results were 120 across the board. When not in boost, AFRs are fairly steady between 14.6-14.8. In boost, they seem ok but I don't hit it hard because I can't get rid of the KR.

Almost seems like the car won't hold it's tune. I'll tune it, it will run great for a week and then "learn" something and it slowly deteriorates to its current condition.

Codes:

[ECM] P0101 - Mass Air Flow (MAF) Sensor Performance (Old) (History) (Immature)
[ECM] P0106 - Manifold Absolute Pressure (MAP) System Performance (Old) (History) (Immature)
[ECM] P0121 - TP Sensor Circuit Insufficient Activity (Old) (History) (Immature)
[ECM] P0172 - Fuel Trim System Rich Bank 1 (Old) (History) (Immature)
[ECM] P0300 - Engine Misfire Detected (Old) (Immature)
[ECM] P0420 - Catalyst System Low Efficiency (SES) (Old) (History) (Current) (Immature)
[ECM] P0442 - Evaporative Emission (EVAP) System Small Leak Detected (Old) (History) (Immature)
[ECM] P0101 - Mass Air Flow (MAF) Sensor Performance
[ECM] P0106 - Manifold Absolute Pressure (MAP) System Performance
[ECM] P0121 - TP Sensor Circuit Insufficient Activity
[ECM] P0172 - Fuel Trim System Rich Bank 1
[ECM] P0420 - Catalyst System Low Efficiency
[ECM] P0442 - Evaporative Emission (EVAP) System Small Leak Detected

 

ur compression seems kinda on the low side

 

those copper plugs are bad **** i heard what are you tuning it with?

i throw p101 and p109 which is crankshaft

 

tuned with HPT

 

HPT

To start, how do I find the evap leak?

 

interesting.. i just took my s/c setup off as well and went to stock intake components.

i reused the stock injectors/ harness and put the tb wiring back to stock.

i think my map sensor is dead or almost anyways.

i have re-loaded my stock tune and that is what im running.


upon first start the car idled very well, but within a few moments of me backing it out of the shop i got all these codes

[ECM] P0106 - Manifold Absolute Pressure (MAP) System Performance (Immature)
[ECM] P0107 - Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage (SES) (Pending) (History) (Immature)
[ECM] P0171 - Fuel Trim System Lean Bank 1 (Old) (Current) (Immature)

car cruises well but lean.... 16-17afr, on idle its pegged lean on my LC1 an stumbles and revvs it self up to 3k rpm

 

my compression was tested at 135 to 140 across all 4

 

sounds like the maf needs to be recalibrated, or it's messed up. i still haven't put in a new maf although I think that is the source of most of my problems. That, and a clogged cat as well as a bad o2 sensor.

 

i picked up a new MAP from my dealer today.. car runs MINT

i have yet to plug in the MAF and take it for a driver... that i will be doing as soon as the laptop is charged so i can log it.

why did you take urs back to stock anyway?

 

It's not, it's still s/c

 

oh i took mine off cuz i was getting a constant missfire on cyl 4 under boost....

 

I don't have any of my stock parts, and I need to go back to stock before I sell it.