'06 Silverado 4.3

[ma123]

Hi folks, I have a v6 silverado with a 5spd and just installed a vortec supercharger kit from an older s10. I run a 12:1 fmu on the stock injectors, with a water/meth kit that I've yet to hook up (haven't gone over 6-8 psi yet).

When the engine is warmed up and driving around for a while, if I put about 70-80% throttle in it, and the boost goes up to about 6-7 psi, it throws codes P0101 and P0106. The motor bogs and it acts as if it's hitting a speed limiter.

I was browsing around on my HPT, and found under engine diagnostics/airflow there are settings for max MAP and MAF readings. Do I simply need to start with tuning for the fuel trims and disable the MAF (found a real good how to on this website). I'm guessing it'll correct this problem?



-> Also, I didn't order the fancy HPtuners that can log my wideband along with the rest of the HPT sensor readings (it's on a separate data logging software that came with the LC-1). This might be a dumb question, I'm having a hard time wrapping my mind around how tuning the fuel trims or VE table can affect my AFR... I mean, how can driving it around as it is right now and collecting data for the fuel and filling in the gaps richen up the fuel system?

Do I need to gather the log data and then make the overall fuel trim table some % richer than they are now and kind of guess and check till I lower my AFR? Again I'm new with this so if you couldnt tell...

AFR is at a steady 14.1-14.9 now and the goal is around 11. (just took the AFR reading today so I'm not going to be boosting anymore with it being this lean)

[Bill@HPTuners]

P0101

Circuit Description
The Mass Air Flow (MAF) sensor measures the amount of air ingested by the engine. The direct measurement of the air entering the engine is more accurate than calculating the airflow from the MAP, the IAT and the engine speed (speed/density). The MAF sensor has a battery feed, ground, and a signal circuit.
The MAF sensor used on this engine is a hot wire type. This engine uses the MAF sensor to measure air flow rate. The MAF output frequency is a function of the power required to keep the air flow sensing elements (hot wires) at a fixed temperature above the ambient temperature. Air flowing through the sensor cools the sensing elements. The amount of cooling is proportional to the amount of air flow. The MAF sensor requires a greater amount of current in order to maintain the hot wires at a constant temperature as the air flow increases. The MAF sensor converts the changes in current draw to a frequency signal read by the PCM. The PCM calculates the air flow (grams per second) based on this signal.
The PCM monitors the MAF sensor frequency. The PCM can determine if the sensor is stuck low, stuck high, not providing the airflow value expected for a given operating condition, or that the signal appears to be stuck based on a lack of signal variation expected during the normal operation. This diagnostic tests the range/performance of the MAF sensor. The MAF system performance or rationality diagnostic uses the MAP, the IAT, and the engine speed to calculate an expected airflow rate. The PCM then compares the rate to the actual measured airflow from the MAF sensor. The PCM only compares the actual MAF value and the calculated value during conditions where the values are likely to match. This DTC sets if the actual MAF reading is not within a predetermined range of the calculated reading.

Conditions for Running the DTC

• DTCs P0102, P0103, P0107, P0108, P0121, P0122, P0123 not set.
• The engine is running.
• The TP sensor angle is less than 50% and the engine vacuum (BARO-MAP) is greater than 65 kPa.
• The system voltage is greater than 10 volts but less than 16 volts.
• The change in TP sensor is less than 3%.
• All above conditions stable for 2.0 seconds.

Conditions for Setting the DTC

• The MAF frequency is 50% different from the speed density calculation.
• All conditions met for 5.0 seconds.

Action Taken When the DTC Sets

• The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
• The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure records.
• The PCM utilizes speed density (RPM, MAP, IAT) for fuel management.

Conditions for Clearing the MIL/DTC

• The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
• A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
• Use a scan tool in order to clear the MIL and the DTC.

Diagnostic Aids
Important

• Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM.
• For any test that requires probing the PCM or component harness connectors, use the Connector Test Adapter Kit J 35616-A . Using this kit prevents damage to the harness connector terminals. Refer to Using Connector Test Adapters in Wiring Systems.

• The following may cause an intermittent:
  • Mis-routed harness
  • Rubbed through wire insulation
  • Broken wire inside the insulation
• Any un-metered air may cause this DTC to set. Inspect for the following:
  • An engine vacuum leak
  • The PCV system for vacuum leaks
  • An incorrect PCV valve
  • The engine oil dip stick not fully seated
• For an intermittent, refer to Symptoms .

Test Description
The numbers below refer to the step numbers on the diagnostic table.

1. The MAF system performance or rationality diagnostic uses the MAP sensor signal along with other inputs in order to calculate an expected airflow rate. The PCM then compares the expected flow rate to the actual measured airflow from the MAF sensor. The first few steps of this table verify that the MAP sensor is working properly. Correct any MAP sensor DTCs first. Refer to DTC P0107 Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage if the MAP sensor voltage is less than 0.8 volts. Refer to DTC P0108 Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage if the MAP sensor voltage is greater than 4.0 volts.

1. Twist the sensor towards the front of the vehicle and lift upward in order to remove the MAP sensor.

1. Using the Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can also help determine how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed.

1. Any un-metered air causes this DTC to set. Inspect the PCV system for vacuum leaks. Also inspect the dip stick for being pulled out. Inspect the oil fill cap for being loose.

1. This step verifies the signal circuit from the MAF sensor electrical connector to the PCM.

1. This step verifies whether a ground and B+ circuit is available.

1. This step tests the signal circuit for an open.

1. This step tests the signal circuit for a short to B+.

[Bill@HPTuners]

DTC P0106

Circuit Description

The manifold absolute pressure (MAP) sensor responds to pressure changes in the intake manifold. The pressure changes occur based on the engine load. The MAP sensor has the following circuits:

• A 5-volt reference circuit
• A low reference circuit
• A MAP sensor signal circuit

The powertrain control module (PCM) supplies 5 volts to the MAP sensor on the 5-volt reference circuit. The PCM, also, provides a ground on the low reference circuit. The MAP sensor provides a signal to the PCM on the MAP sensor signal circuit which is relative to the pressure changes in the manifold. The PCM should detect a low signal voltage at a low MAP, such as during an idle or a deceleration. The PCM should detect a high signal voltage at a high MAP, such as the ignition is ON, with the engine OFF, or at a wide-open throttle (WOT). The MAP sensor is also used in order to determine the barometric pressure (BARO). This occurs when the ignition switch is turned ON, with the engine OFF. The BARO reading may also be updated whenever the engine is operated at WOT. The PCM monitors the MAP sensor signal for voltage outside of the normal range.
The PCM calculates a predicted value for the MAP sensor based on throttle position (TP) and engine speed. The PCM then compares the predicted value to the actual MAP sensor signal. If the PCM detects that the MAP sensor signal is not within the predicted range, DTC P0106 sets.
Conditions for Running the DTC

• DTCs P0101, P0102, P0103, P0107, P0108, P0120, P0220, P0442, P0443, P0446, P0455, P1125, P1514, P1515, P1516, P1518, P2108, P2120, P2121, P2125, P2126, P2130, P2131, P2135 are not set.
• The engine speed is between 400-5,000 RPM.
• The change in engine speed is less than 125 RPM.
• Traction control is not active.
• The A/C compressor clutch is steady.
• The power steering is stable.
• The clutch switch state does not change.
• The brake switch state does not change.
• The above conditions are met for 1 second.

Conditions for Setting the DTC

The PCM detects that the MAP sensor voltage is not within the predicted range for 2 seconds.
Action Taken When the DTC Sets

• The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
• The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

• The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
• A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
• Clear the MIL and the DTC with a scan tool.

Test Description

The numbers below refer to the step numbers on the diagnostic table.
4.This step tests the ability of the MAP sensor to correctly indicate BARO.
6.This step tests the ability of the MAP sensor to respond to an increase in engine vacuum.
8.This step tests for a proper MAP sensor pressure with an applied vacuum.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics
Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Inspect for the following conditions:

• Vacuum hoses that are disconnected, damaged, or incorrectly routed
• Manifold absolute pressure (MAP) sensor seal that is missing or damaged
• Restrictions in the MAP sensor vacuum source
• Intake manifold vacuum leaks

[ma123]

Thanks for all the info Bill, I shouldve given more diagnostic info when I wrote about the codes.

When I turn the engine off after these codes are thrown, let it cool and drive it a time or two, the codes disappear like your info says they should (after 3 ignition cycles it doesnt fail).

And according to this info, the p0106 MAP code has to be triggered before the p0101 MAF code. So that means my MAF sensor is fine, it's just reading a messed up pressure from the MAP sensor.

It wouldn't be a vacuum leak, because these codes don't trip at 3-4 psi for like 4-5 seconds... A vacuum leak that would be detected at 7psi but not at 3-4 psi just doesn't sound right.. I mean if it were there it'd likely be there at 4psi too. Also I'm not throwing any codes that show a certain bank is lean, so I'm not positive it's a vacuum leak

Here's what gets my attention:
"The PCM calculates a predicted value for the MAP sensor based on throttle position (TP) and engine speed. The PCM then compares the predicted value to the actual MAP sensor signal. If the PCM detects that the MAP sensor signal is not within the predicted range, DTC P0106 sets."

What does it mean by the 'MAP sensor signal is not within the predicted range'. Is it possible at all that the huge amounts of air coming in on the stock tune would make it trigger this code outright? I guess the only way I could find out is start tuning in speed density mode and see if it triggers the p0106 code again? I hate to do this under boost cuz the AFR is so lean

[ma123]

I'm boosting through the valve cover ventilation tube to the crankcase from the bypass/discharge valve I thought about it a lot and took a look at the info of yours bill, and that has to be what it is. I can't think of anything else.

[ma123]

I put a filter on the valve cover and it's not showing anymore codes which is good, I'm one step closer to start the tuning.

I called vortech s/c tech support and they said if I want to tune using speed density mode from the MAP sensor (after I disable the MAF) then I need to run a one way check valve on the vacuum line to the MAP sensor... do I need this before I start tuning the fuel trims?
Thanks, Mike

[UR50SLO]

Hi folks, I have a v6 silverado with a 5spd and just installed a vortec supercharger kit from an older s10. I run a 12:1 fmu on the stock injectors, with a water/meth kit that I've yet to hook up (haven't gone over 6-8 psi yet).

Get rid of that FMU.. it's going to kill your engine.

Get a Marine Intake from ebay for 199.00 and put the correct size injectors in it then fuel it with Hptuners.
Go to www.fullthrottlev6.com under 4.3L tech for more info on my Marine intake thread.
~Scott

[Bill@HPTuners]

http://www.fullthrottlev6.com/forums...ghlight=marine

I thought about doing this conversion when the intake first became available(I had a 98 S-10 with a powerdyne) fueling via the pcm will be a better way than fueling via an fmu IMO as stated.

[UR50SLO]

I thought about doing this conversion when the intake first became available(I had a 98 S-10 with a powerdyne) fueling via the pcm will be a better way than fueling via an fmu IMO as stated.

It's been a great conversion for us over the last 30,000mi. It's 20lbs heavier than the stock manifold but worth it.
Better fuel atomization point of entry smoother inside plenum with no junk in it and with
the HPTuners program you can dial in the injector size and edit timing for boost.
We will be over 170,000mi on stock engine soon.
~Scott