Cannot get 2-bar MAP PID for P59
Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
Cannot get 2-bar MAP PID for P59 Hey all, I'm trying to tune my friends truck (2006 Silverado HD with an LQ4), and I'm having trouble getting the EQ error boost table to work correctly.
I asked for help on the HPTuners forum, and was instructed I needed to delete the stock MAP sensor PID and replace it with a 2-bar PID. I searched the help document and found the instructions on connecting to the car, deleting the stock MAP PID and then selecting the 2-bar PID, however no matter what I've tried I cannot get the 2 bar pid to show up. Am I missing a step (or just missing something entirely?) With the stock MAP PID it seemed to read above 105kPa just fine, but I can't get it to populate in the graph.
Attached log, tune, and the channels/graphs I have setup.
Thanks!
I asked for help on the HPTuners forum, and was instructed I needed to delete the stock MAP sensor PID and replace it with a 2-bar PID. I searched the help document and found the instructions on connecting to the car, deleting the stock MAP PID and then selecting the 2-bar PID, however no matter what I've tried I cannot get the 2 bar pid to show up. Am I missing a step (or just missing something entirely?) With the stock MAP PID it seemed to read above 105kPa just fine, but I can't get it to populate in the graph.
Attached log, tune, and the channels/graphs I have setup.
Thanks!
TECH Fanatic
Joined: Jul 2022
Posts: 1,032
Likes: 389
From: Alaska
First peak at your spark table, And I gotta point out you have a LOT more advance than I can get away with in the 2400 to 4000 rpm range " Unless you are feeding that monster straight alcohol, you are going to have trouble.
For reference, on 90 octane unleaded, I make 8 degrees at 3600, and 9 degrees spark at 4000 rpm....
For reference, on 90 octane unleaded, I make 8 degrees at 3600, and 9 degrees spark at 4000 rpm....
In the actual PID list, change the 2 bar manifold sensor to Kpa unit, it does not display properly if you pick PSI
To get your graph to work properly;
Change the "Row axis" units to Kpa and lower the cell hit required count to 0 or 5.
The issue was you had the row axis to display in PSI, but was using Kpa for the row values, and the cell count of 20, you aren't spending enough time in that cell, long enough, for it to record any data.
If you want to to see it in PSI, you will have to make a boost math channel. That's what I did on mine.
There is a pre defined boost math channel in the airflow folder, but it's setup to to read and display in kpa. You will need to make your own and select PSI instead.
To get your graph to work properly;
Change the "Row axis" units to Kpa and lower the cell hit required count to 0 or 5.
The issue was you had the row axis to display in PSI, but was using Kpa for the row values, and the cell count of 20, you aren't spending enough time in that cell, long enough, for it to record any data.
If you want to to see it in PSI, you will have to make a boost math channel. That's what I did on mine.
There is a pre defined boost math channel in the airflow folder, but it's setup to to read and display in kpa. You will need to make your own and select PSI instead.
Last edited by LilJayV10; Oct 20, 2025 at 08:27 PM.
Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
I was worried that might be the case. Considering the other weird stuff done to this (adding a tac module for starters) im hesitant to slap a new OS and risk bugging the thing out.
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Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
Got it figured out. Still wont show a specific 2-bar MAP for a PID, but using the generic sensor in the graph (and fixing the units, thanks LilJay!) is working fine. Thanks all!
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