View Full Version : E78 Cruze 1.4L TC tuning

March 9th, 2015, 08:03 AM
I've spent several months working on a 2011 Cruze with the 1.4L running it on fuels such as gasoline, methanol & ethanol. We've run completely stock tables except for the ethanol related settings. Since we upgraded the injectors for more flow capacity I've had a hard time getting the expected values out. Was hoping from some clarification on some of our issues.

We are equipped with a WB02 and 2) Type K thermocouples, we also have a dynamometer

My partial and low loads look great, but we can't get any good numbers during >80% engine load.
AFRs of .6-.75 lambda EVERYTIME, with or without the upgraded injectors
Cat convertor temps are 150-200C below cat protection mode.
DeltaMAP (FRP+BARO[82kPa]-MAP) remain from 300-450kPa

What sets the vehicle into Boost Protection mode?
B7021 - Maximum Pressure Ratio shows units of mg from 124.75 to 151.2mg; however the MAF gives a signal of only 60,000-107,000 mg/s maximum. Do I need to be using mg/cyl? Either the X-axis is supposed to be in the hundreds of thousands or we're always running with a limit of 3.0. We've only attained 2.5-2.68 MAP/Baro ratios so far. This shouldn't' be limiting us.
B7020 - Since we're doing steady state loading with slowly increasing values, we shouldnt' be limited by this MAP/Baro ratio
B7009 - The vehicle is always run at 100C (operating temp), which would put maximum boost at 225kPa, we've only attained 220 a few times, so this shouldn't be limiting us.
B7008 - For my elevation, boost control will not enter closed loop because we've not exceeded these numbers
B7011 - Same problem as the B7021 chart, this shows values of .27-.725 grams. When driving, the vehicle goes from 15-107 g/s. I must be off on my units again.

I'm not trying to turn up the boost or remove limits, just understand what is actually kicking in to make our RIDICULOUS 0.6 lambda occur. Our Torque Predicted vs Demanded are always off kilter, so we've been quite limited for final power output. We're tuning for EPA emissions requirements, so I need to stay fairly close to OEM values. I dont' see how this car could possibly have passed certification if it runs that rich during WOT no matter the conditions.

April 14th, 2015, 09:28 AM

Bucking was caused by a failing spark plug coil pack (all 1 unit). Back to running well. THOUGH, still have crazy high lambda readings during WOT

April 15th, 2015, 11:57 PM
post your tune, if it's anything like the e83 ecu I might have some suggestions for you.

April 16th, 2015, 01:20 AM
post your tune, if it's anything like the e83 ecu I might have some suggestions for you.

Thanks for the offer! The issues were occurring with every tune, whether stock or altered. Which solidified a hardware issue.

I really don't have much changed on the latest tune that y'all can access either. We've got a custom calibration file with access to another 200+ ethanol related tables that have been changed to make FFV operation better. I've kept all my limiters in place but upped Torque Limit charts [B7017 & B7018] 15% on E80, sloping down to stock values for E0. PE Mode E80 commanded fuel [B3670] was also reduced (higher lambda) by a few points as well. We're stock drivability for our testing. Though we have run several tunes with 42 lb/hr injectors and gotten some great power gains! These little cars are a hoot to drive once you get rolling.

April 29th, 2015, 01:46 AM
Who did the custom cal for you? I'm looking to have some tables added as well.

April 29th, 2015, 02:03 AM
drop me an email

April 29th, 2015, 02:09 AM