JS City Goblin - 2010 LS

JSATX

Goblin Guru
Well I did a quick evaluation this morning after the drive last night (and after the Adrenalin died down, good grief) and have two issues I’ll be working on.

I’m now throwing code P0106 which is a MAP sensor problem, until I get the computer hooked up to monitor while driving I can’t know much more.

Before the ZZP tune my fuel pressure always stayed steady at 55-60psi, right where it’s supposed to be. After the tune the pressure stays at a constant 85-90psi. This makes me uncomfortable as the pump and lines are simply not designed to run at this pressure. The fuel pump is much louder and sounds strained. I am running the Siemens 60# injectors as recommended by ZZP.
 

SliderR1

Well-Known Member
that stock sensor might be maxed out under boost - did you install a larger map sensor? You'll need to re-tune if a larger sensor is installed, too...
 

Briann1177

Goblin Guru
How much boost are you expecting to run? Isn't 4 bar good for like > 30 PSI or so?

*Edit* 4 bar is good for ~43 PSI.
 
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JSATX

Goblin Guru
How much boost are you expecting to run? Isn't 4 bar good for like > 30 PSI or so?
Yeah I have no intention of going over 7psi with the current setup. The plastic intake manifold is only good to about 10psi.

I only hit 5psi on the test run and it was breaking loose easily.
 

Briann1177

Goblin Guru
With the GM stage one kit which provides a 3 bar MAP, the instructions say you're not supposed to run it at stock (2 bar) pressures for very long. I guess running the sensors at the bottom of their range can damage them.
 

JSATX

Goblin Guru
With the GM stage one kit which provides a 3 bar MAP, the instructions say you're not supposed to run it at stock (2 bar) pressures for very long. I guess running the sensors at the bottom of their range can damage them.
Interesting. I had not heard that. Maybe I should just use the stock sensor, but that would require retune...
 

SliderR1

Well-Known Member
another thing to check is the wiring to the sensor.. There are a lot of guys getting the MAP code on LS engines and it ends up being a broken wire to the sensor itself.
 

Briann1177

Goblin Guru
Maybe damage is the wrong word. I'll see if I can find that again. It was on cobaltss.net. Most sensors work best in a range and and they don't typically like being run at the extreme ends.
 

JSATX

Goblin Guru
ZZP said fuel pressure can’t be changed by ecm, I don’t really understand that since I thought it took the information from the MAP and had built in boost reference fuel pressure.

They said check the fuel regulator and return lines. The only return line is before the filter, it’s a new filter so that just leaves regulator
 

JSATX

Goblin Guru
Wait a sec...Since when is there a regulator on a returnless fuel rail? I thought it was all software based
 

JSATX

Goblin Guru
More bad news. The car dies everytime the the accelerator pedal is floored under load. If i gently accelerate up to about 3k and punch it, its fine, if i try and punch it from low rpm I hear the turbo spool up and the throttle slams shut

Edit: I’m losing ground. Just tried it again, and lost dash display and gauge lights when it lost power. So once again a lose ground is causing headaches
 
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JSATX

Goblin Guru
Found the problem with losing connection. The big J1 plug on ECU was having issues for some reason. It was latched but not making good connection. I blew it out with compressed air and the problem has so far gone away.

The other issues haven’t though. Car will not accelerate at any RPM under approximately 3k. It’s the strangest thing I’ve ever seen, if you very carefully nurse it up to around 3k and then gun it it goes like a bat out of hell. But if you sharply press the throttle at any rpm under ~3000 it immediately loses all power and goes back to idle like the throttle is slamming shut or the fuel is getting cut.
 

JSATX

Goblin Guru
The fuel gauge is behind me so I can’t quite tell. I’ll try and watch it next time. It shuts down hard. Like no throttle response, no fuel, something definitely computer related. My guess is it’s sensing a very lean condition in that range and cutting throttle.

Without good data logging software it’s a guessing game. I’ll eventually buy HPtuners it’s just so expensive.
 

SliderR1

Well-Known Member
without tuning software, swapping the sensor out will make things worse...the software will be expecting data from the 4bar, if it is in fact tuned for a 4bar...

which PCM are you running again?
 
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