HHR SS 2.0 LNF/LDK Engine Power Reduced?

[drummerboy0088]

I just did a 3" catless exhaust setup for my 2.0 LDK HHR SS, and now after going 100% throttle I'll get a reduced engine power warning as soon as I let off the trottle. No engine light, but P0087 - Fuel/Rail pressure system too low code comes up. I'm running opel injectors on 93 pump gas.

Never got this message/code before the exhaust install.

Here's what I'm tuned for:
LDK motor
Opel Injectors
TTR Intake Manifold
ZZP High Flow Air Intake
ZZP intercooler and charge pipes
3 bar maps
Forge VTA bypass valve
MAF in lower charge pipe
ZZP 02 housing
ZZP 3" catless downpipe with angled o2 bung
3" exhaust tubing with Borla ProXS muffler and inter-cooled tip.

n costa log h.hpl

[TurboCobalt]

at t = 05:41.882, your waste gate duty cycle is oscillating when it shouldn't, you can see that your MAP is also oscillating as a result. Did you mess with wastegate DC table?
at t = 06:40.261, at 56% accel pedal you are boosting more than 255kpa map, car must have pretty bad drive-ability, also your map overshoots your desired boost by more than 20kpa, again, what did you do to the wastegate dutycycle table? (or boost PID gains)
at t= 10:30.563 you can see that 56% accel pedal does the exact same thing as 100% accel pedal, again drive-ability concerns.
at t = 10:32.563, desired fuel pressure is 17.6MPa, measured fuel pressure is 15.5MPa. looking at my cobalt's datalogs, the highest fuel pressure commanded is 15MPa, i don't know if the high pressure fuel pump is capable of more than 15ish MPa, why did you bump up the desired fuel pressure. (anyway, you changing the request might have something to do with the diagnostic setting) I looked it up in my tune and desired pressure only goes up to 15MPa, don't know why you pushed it to 17MPa, but that's why you are setting the diagnostic.

please record "boost low res " in your future logs, MAP variable maxes out and we can't see how high your pressure goes without the other variable recorded.

post your tune (if you're willing to share it) also can you share who tuned this?
i think there might be more problems in your tune beyond fuel pressure.

[drummerboy0088]

Thanks for the input. I have no problem sharing the tune. It was done by a company that's big in the platform.

I bought HPT when I installed the new motor (with new k04) and bolt ons listed above but I figured I would rely on someone who was more knowledgeable to create a base tune with what mods I did since I'm new to this. Since they see builds like this and more, I figured they would know how to tune for it.

This setup also has bout 2k miles, so it's all fairly new.

[TurboCobalt]

First thing first, what are you trying to achieve with this car?

Here are my comments, (just opinions, not necessarily right):
Desired Air Load table may be too high. I think you can achieve the same result with a lower DAL table (that's just an opinion though)
Maximul Knock Retard is reduced a lot, i wouldn't do this, when you limit it like this it doesn't allow the controller to protect the engine against knock. If i were you i'd move this back to stock.
Wastegate Duty Cycle Correction - as expected about 8% higher than stock (compare it to a stock tune, make sure to also look at the axis). if anything with all your mods this should be just a couple % lower than stock or the same as stock, not higher. if i were you i'd move this back to stock (might need more logging and tuning though to make sure)
Desired fuel pressure table - as expected set to 17 and 18 , should probably be left at 15MPa, especially with the bigger injectors, no reason to bump up the pressure. if i were you i'd move this back to stock.

[drummerboy0088]

This is my garage queen - I like to take it to shows, and wanted to mod a bit to give it a bit more life.

The turbo fried 2 months after buying the car, so I did all the upgrades to start over fresh. Even did new vacuum and coolant lines. Only thing original is the trans (81k miles on it). Eventually, I?ll do more mods and strengthen internals, but wanted to get the car back up and running with what it has now.

Thanks for the input, I?ll adjust what you recommended to see how it responds.

[salvadorz24]

What company tuned your car? You deserve a full refund, they just basically increased your boost and add 2-3 degrees of timing, but in fact you are only seeing 6-7* of timing, stock timing is around 10*; and also they turn off a lot of codes.

[drummerboy0088]

Thanks for the input. I'd like to find a local dyno (philly, PA) and have it Dyno'ed to be correct - but no one I found touches this platform.

I'm going to be reading up in the LNF guide thread to adjust the tune myself. Most likely bring it back to stock, and adjust accordingly.