Pontiac G8 Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
320 Posts
Discussion Starter · #1 ·
I have tracked down why my stability trac comes on at, or below 1500rpm. Im also throwing a map sensor code p0556. I have verified that i have a good map sensor and maf. I checked my vacuum and for the heads and cam setup im running resulted in a low 11inches of vacuum. I kind of read that some corvette guy were getting similar issues. From what I can understand the map sensor is issuing a self check type test against so air flow table, when it does this it doesnt match resulting in a p0556. Is their a way to change the table to make the test happen at a higher rpm, or disable it all together?
 

·
Premium Member
Joined
·
4,637 Posts
I'm reading that P0556 is the Brake Booster sensor (if your posted code is correct). An it is detecting a loss (less vacuum) in the Brake Booster as compared to the actual value in the intake manifold at some point. It says it want's to see the same value as the manifold at all times. If not, it reports that fault code, and if necessary will modify the engine running conditions, to try to correct same.
If its *that* code, maybe you could perform an in-depth checkout of that vacuum plumbing from the manifold to the booster. If all OK, maybe the sensor itself is sending out an incorrect signal back to the ECM, causing *it* to alter the controls to the engine.
 

·
Registered
Joined
·
320 Posts
Discussion Starter · #3 ·
That's my bad, it's throw that code also before but I believe that it because the map sensor code. When I read the code for it, it says map or baro out of performance.
P0106 code is what I meant.
 

·
Premium Member
Joined
·
4,637 Posts
If those established models in the ECM can be modified, that would be nice. Since its monitoring the TB position sensors, the MAF and MAP to see if all is well and correct, maybe its getting confused due to the mod work performed on your car (with what sounds like a very low vacuum reading). Sounds like a real savvy type laptop person is required on this one.
 

·
Registered
Joined
·
320 Posts
Discussion Starter · #5 ·
That's what I'm thinking. I'm just curious if the cmr program will allow certain modifications.
 

·
Custom Tuner
Joined
·
153 Posts
can't do anything about stabilitrak in the tune file... just hold the traction control button on your dash for about 5-10 seconds and it will disable...

as for the brake booster code... you've got an issue with your car... shouldn't have to disable that trouble code in the tune for any reason...
 

·
Registered
Joined
·
590 Posts
Off topic, but why would you have to hold it down? Just a simple press turns it off.

Sent from AutoGuide.com App
 

·
Custom Tuner
Joined
·
153 Posts
just simply pressing the traction control button quick only disables/turns off the traction control, not the stabilitrak...

to disable the stabilitrak, you have to hold the button for 5-10 seconds...and it will show you a message that the stabilitrak is now disabled...
 

·
Registered
Joined
·
590 Posts

·
Custom Tuner
Joined
·
153 Posts

·
Registered
Joined
·
320 Posts
Discussion Starter · #11 ·
I'm not wanting to modify anything with the stability. I'm just curious if their is a airflow chart for the map sensor rationality test, that can be manipulated. I want to raise the minimal rpm that the test can occur.
 

·
Registered
Joined
·
590 Posts

·
Registered
Joined
·
320 Posts
Discussion Starter · #13 ·
Bump for anyone with in knowledge of the map sensor rationality test.
 

·
HPT Pro Tuner
Joined
·
3,815 Posts
The test for P0106 can be disabled, common practice for big cams, whether CMR can do it or not is a different thing.
And in the G8, i don't think you'll accomplish much holding the TC button :), In a Corvette for example yes, but not in the G8, StabiliTrack and Traction control are BOTH on/off when you PRESS the button. No need to hold it down for 3-5 sec, Is in the manual if you want to double check lol.
 
1 - 14 of 14 Posts
Top