P0106 Code on a GMC: MAP Sensor Performance (GMC Guide)

P0106 on a GMC is "Manifold Absolute Pressure (MAP) Sensor Performance." The MAP reading is in range, but it does not agree with what the engine computer calculates it should be. That makes it a logic code, not a wiring code — and on a GMC the cause is very often not the sensor. GM has documented P0106 on the Sierra and Yukon several times, and the most important document is a surprise: on 2014–2021 Sierra and Yukon V8s, GM says P0106 together with P0506 can mean a broken valve spring. GM has also replaced MAP sensors outright on early-2021 Sierra, Yukon and Savana builds, blamed loose intake bolts on the 2.5L Canyon and 2.0T Acadia, found a pinched harness on the 2016 Sierra and Yukon, and traced it to MAP wires broken inside their insulation on the 2004–2012 Canyon.

What Does P0106 Mean on a GMC?

The MAP sensor measures absolute pressure inside the intake manifold. At idle, with the throttle nearly closed, manifold pressure is low (high vacuum). At wide-open throttle it rises close to atmospheric pressure. With the key on and the engine off, it should read the same as the barometric pressure where the truck is parked. The engine control module (ECM) uses the reading for load, fuel and spark calculations.

GM's wording for P0106 is MAP Sensor Performance; older GM truck tables call it "MAP Sensor Range/Performance (Rationality)." GM's 2019 tables for the Sierra and Yukon V8 group describe it as a failure "such as when a MAP value is stuck in range." The separation from the neighboring codes matters:

How GM Tests the MAP Sensor on GMC Engines

GM's test has changed a lot over the years, and the version your GMC runs explains what is likely to set it.

Vortec trucks, late 1990s. GM's 1999 table for the 5.7L L31 in C/K pickups and G-vans (the Sierra and Savana) checks whether the MAP value falls inside a window based on throttle position, at a steady idle. It needs 24 failures in 100 samples and is a Type B (two-trip) code. The same table carries the circuit codes P0107 and P0108.

Gen III V8s, 2001–2006. GM's truck tables compare measured MAP with a predicted MAP from a lookup table of throttle position and rpm. In the 2004 and 2006 tables for the 4.8L, 5.3L and 6.0L, it takes 20 failures in a 30-sample test, Type B. Notably, GM's 2000 table for the first Gen III truck V8s (4.8L LR4, 5.3L LM7, 6.0L LQ4) lists P0107 and P0108 but no P0106, and its 1998–2000 tables for the 7.4L L29 list none either.

Gen IV and Gen V V8s. From the 2007 Gen IV tables onward, GM uses the Intake Flow Rationality Diagnostic. The ECM calculates two modeled manifold pressures from the MAF, throttle position and rpm, and fails P0106 when the measured MAP disagrees with both. GM's 2007 table for the 5.3L LH6 and LY5 sets the limit at 15 kPa and — a detail specific to Active Fuel Management trucks — only runs after at least 2 seconds in all-cylinder mode. GM's 2019 tables for the Sierra and Yukon V8 group (section "L84 / Common") use 22 kPa, between 400 and 5,400 rpm, plus an engine-off check that the MAP reads within the expected atmospheric range after the truck has sat. It is Type B.

The practical consequence is the same in every generation: because "expected MAP" is calculated from other sensors and from how well the engine is breathing, a vacuum leak, a skewed MAF or a mechanical problem inside the engine can make a perfectly good MAP sensor look wrong.

Which GMCs Set P0106

GM's tables list P0106 for the Vortec 4.3L, 5.0L and 5.7L trucks of the late 1990s, the Gen III and Gen IV V8s in the Sierra, Yukon and Savana from 2001, the Gen V 4.3L, 5.3L and 6.2L, and the newer four-cylinders in the Canyon, Terrain and Acadia. GM documents name P0106 on these GMC groups:

• 2014–2019 Sierra (and Sierra Limited) with the 4.3L LV3, 5.3L L83 or 6.2L L86; 2019 new-model Sierra 1500 with the LV3, L82, L84 or L87; 2015–2019 Yukon with the L83 or L86 — broken valve spring, PIP5423B.
• 2020–2021 Sierra (5.3L L82/L84, 6.2L L87, 6.6L L8T) and 2021 Yukon (L84/L87) built July 1–December 16, 2020 — broken valve spring, PIP5752M.
• 2021 Sierra, Sierra HD, Yukon and Savana built January 1–February 15, 2021 — faulty MAP sensor, PIP5787A; plus service update N212332660 for 2021 units in dealer inventory.
• 2016 Sierra 1500, Yukon and Yukon XL — pinched 5-volt reference harness, PIP5344.
• 2015–2017 Canyon 2.5L (LCV) and 2017 Acadia 2.0T (LTG) — loose intake manifold bolts, PIP5529B.
• 2004–2012 Canyon with the 2.8L, 2.9L or 3.7L (LK5, LLV, LLR) — MAP sensor wires broken inside the insulation near the connector, PIP4409F; and, with the Envoy 4.2L, a rough idle from a cam actuator solenoid problem that can store P0106, PIP3694F.
• 2016 Savana with the 4.8L or 6.0L (L20, L96) — hesitation or sag with P0101, P0106, P0121 and P1101, fixed by an ECM update, PI1538.

Duramax diesels have their own P0106 documents — for example PI1257 (2007–2009 Sierra 6.6L LMM, MAP sensor relocated to stop icing) and 19-NA-127 (2019 Canyon 2.8L LWN, an ECM software update). Diesel diagnosis is different and is not covered here.

One gap worth knowing: GM's 2008 and 2011 tables for the 3.6L LLT used in the first-generation Acadia list no P0106. On a 2007–2012 Acadia, an intake air problem usually shows up as a MAF, fuel trim or P1101 code instead. If a generic scanner shows P0106 on one of those, double-check the code and the engine.

The Sierra and Yukon Valve Spring Story

This is the GMC-specific reason not to buy a MAP sensor first.

PIP5423B covers 2014–2019 Sierra and Sierra Limited with the 4.3L LV3, 5.3L L83 and 6.2L L86, the 2019 new-model Sierra 1500, and the 2015–2019 Yukon with the L83 or L86 (alongside Chevrolet, Cadillac and Corvette V8s). The condition is a service engine soon lamp with P0106 and P0506 — idle speed lower than expected. GM's stated cause: a broken valve spring. The procedure is to remove the valve cover and inspect for a broken spring; if one is found, inspect the intake manifold for a collapsed runner. GM says to replace the broken spring if the valve did not drop and damage the engine. GM does not explain in the PI why this pair of codes results. A plausible reading is that a cylinder that cannot seal its intake valve upsets manifold pressure in a way the MAP model cannot explain — but that is our inference, not GM's wording.

PIP5752M repeats the warning for later trucks: 2020–2021 Sierra with the 5.3L L82 or L84, 6.2L L87 or 6.6L L8T, and the 2021 Yukon with the L84 or L87, built between July 1 and December 16, 2020. The complaint is a service engine light, misfire and engine noise with possible P0300, P0106, P0506 and the P3189–P3190 family. After a cylinder leakage test on the affected cylinder, GM's instruction differs by engine: on the 6.2L L87 with less than 800 km (500 miles), replace all valve springs; above that, replace only the broken one. On the 5.3L L82/L84 and the 6.6L L8T, replace only the affected spring. Check the intake runner for that cylinder either way, and if there is cylinder leakage, inspect further for engine damage. GM references Powertrain coverage for these repairs.

So on a 2014-or-later Sierra or Yukon, P0106 with P0506, a misfire code or a ticking noise is a reason to pull a valve cover before replacing anything on the intake.

GM's Other GMC Documents for P0106

PIP5787A — a genuinely bad MAP sensor (2021). For 2021 Sierra and Yukon with the 5.3L L84 or 6.2L L87, and the Sierra HD and Savana with the 6.6L L8T, built January 1 to February 15, 2021, GM lists P00C7 ("Intake Air Pressure Measurement System Sensor and Multiple Sensors Correlation"), with P0106 and P0108 possibly present. GM's cause is a faulty MAP sensor, and the correction is to replace it and re-evaluate. This is one of the few GM documents for P0106 where the sensor really is the answer — and only for that narrow build window.

N212332660 — dealer inventory only (2021). GM's service update covered about 540 U.S. vehicles, including 2021 Sierra LD and HD, Savana, Yukon and Yukon XL, for an erratic MAP signal with P0106 and P0108. Dealers replaced the MAP sensor (part 12711681). It applied to vehicles in dealer inventory only and expired May 31, 2022, so for practical purposes it has passed — though a dealer VIN check is free.

PIP5344 — the 5-volt reference (2016). For the 2016 Sierra 1500, Yukon and Yukon XL with the 4.3L LV3, 5.3L L83 or 6.2L L86, GM lists a service engine lamp and/or reduced power with any of P0106, P0107, P0697, P2122, P2123, P2127, P2128 and P2138 — codes that share 5-volt reference 3. If published diagnostics are inconclusive, GM says to inspect the harness near the left instrument panel junction block, where it can be pinched on a mounting stud. See our 5-volt reference circuit guide.

PIP4409F — broken MAP wires on the first-generation Canyon. For the 2004–2012 Canyon with the 2.8L LK5, 2.9L LLV or 3.7L LLR, GM describes an intermittent rough running concern and/or SES light, history misfires on all cylinders, and any of P0106, P0107, P0171, P0300, P0502, P1107 and P2431. If service information does not find the cause, GM says to inspect all MAP sensor circuits for being broken inside the insulation near the MAP sensor connector — "typically, the break will be within inches of the MAP sensor connector." The repair uses TXL wire of the correct size and new terminals. A wire that looks intact can still be broken, so a wiggle test while watching MAP data matters here.

PIP3694F — cam actuator solenoid on the inline engines. For the 2004–2012 Canyon and 2004–2011 Envoy with the L52, LK5, LL8, LLR or LLV, GM covers belt noise, rough idle and/or P0014 and P0017, adding that "if a rough idle is experienced, a P0106 may also be stored." The checks are the camshaft actuator solenoid screens and crankshaft end play. On those trucks, P0106 alongside cam codes points at the cam system, not the MAP sensor.

PI1538 — 2016 Savana software. For the 2016 Savana with the 4.8L L20 or 6.0L L96, GM lists a slight hesitation or sag with P0101, P0106, P0121 and P1101. If service information does not find a root cause, GM says to update the ECM, referencing Emission coverage.

PIP5529B — loose intake manifold bolts. For the 2015–2017 Canyon 2.5L (LCV) and the 2017 Acadia 2.0T (LTG), GM lists stall, hesitation and any combination of P0068, P0101, P0106, P0131, P0137, P0171, P0324, P0326, P0331 and P0506. If service information does not lead to a fix, GM says to check the intake manifold bolts for looseness, then remove one bolt at a time, add medium-strength threadlocker and torque them in sequence to the service specification. GM says not to replace the intake manifold gasket unless testing shows it still leaks after the bolts are torqued. The bulletin labor time is 0.4 hour.

Symptoms of P0106

• Service engine soon or check engine light
• Idle lower than normal, often logged as P0506
• Rough idle, hesitation or stalling — named in PIP5529B on the Canyon 2.5L and Acadia 2.0T
• Misfire and a ticking or tapping noise on a 2014–2021 V8 with a broken valve spring
• Reduced engine power when the shared 5-volt reference is involved (PIP5344)
• Lean codes such as P0171 when a vacuum leak is the root cause
• Sometimes no driveability change at all

Causes and How to Confirm Each

How Is P0106 Diagnosed?

1. Record every code and freeze frame. P0106 with P0171 suggests a leak; with P0506 or a misfire on a V8, a valve spring; with P2122/P2127/P0697, the 5-volt reference; with P00C7 on a 2021, the sensor itself.
2. Have the VIN checked for PIs and updates — especially on a 2014–2021 Sierra or Yukon, a 2016 or 2021 Savana, a 2021 Sierra HD, or any Canyon.
3. Compare MAP to barometric pressure with the key on and engine off after the truck has sat. They should read about the same.
4. Watch MAP at idle and on a snap of the throttle. It should drop at idle and respond quickly and smoothly.
5. Listen to the valve train on a V8 with P0506 or misfire codes, and plan a valve cover inspection before buying intake parts.
6. Smoke test the intake and, on the 2.5L and 2.0T, check the intake manifold bolts.
7. Check the 5-volt reference and connector if other sensors on the same reference also have codes.
8. Replace the sensor last, unless a PI for your build dates says otherwise, then clear and road test.

Parts and Cost

Order a MAP sensor by VIN. GM changed MAP sensors across generations, and turbocharged Canyon, Terrain and Acadia engines also carry a separate boost pressure sensor that is not interchangeable.

GM Documents That Name P0106 on GMCs

Have a dealer check your VIN against current bulletins and campaigns rather than relying on any article, including this one.

What Other P0106 Pages Get Wrong

• "P0106 means a bad MAP sensor." On GMC trucks, GM's documents more often point at valve springs, bolts or wiring. Only a narrow early-2021 build window has GM replacing the sensor.
• "It's harmless on a V8." With P0506 or misfire codes on a 2014–2021 Sierra or Yukon, GM sends technicians looking for a broken valve spring.
• "Replace the intake gasket." On the Canyon 2.5L and Acadia 2.0T, GM says retorque the bolts with threadlocker first.
• "Every GMC uses P0106." GM's tables for the 2000 Gen III truck V8s, the 7.4L and the first-generation Acadia 3.6L do not list it.
• Treating it as a wiring code. Open and shorted circuits normally set P0107 or P0108 — though a shared 5-volt reference fault can set P0106 too, as PIP5344 shows.

For the general GM explanation of this code, see our P0106 GM guide. Cadillac Escalade owners will find the same valve spring documents in our Cadillac P0106 guide.

Frequently Asked Questions

Is P0106 serious on a Sierra or Yukon?

It can be. By itself it is often a driveability or emissions issue, but on 2014–2021 V8s GM links P0106 with P0506 or misfire codes to a possible broken valve spring. If you hear a tick or the engine misfires, have it inspected promptly.

Why does my GMC show P0106 and P0506 together?

GM's PIP5423B links that exact pair on 2014–2019 Sierra and 2015–2019 Yukon V8s (and the 2019 Sierra 1500) to a broken valve spring. The check is a valve cover inspection, plus an intake runner inspection if a spring is broken.

Should I just replace the MAP sensor?

Not as a first step on most GMCs. The exception is a 2021 Sierra, Sierra HD, Yukon or Savana built between January 1 and February 15, 2021 with P00C7, covered by PIP5787A. Check your VIN first.

Where is the MAP sensor on a GMC V8?

On the Gen III, IV and V small-block V8s it sits on the intake manifold, sealed to it by an O-ring. Inspect that seal and the port when the sensor is out — oil and carbon can skew the reading. Confirm the exact location for your engine in the service information before buying parts.

My 2010 Acadia never sets P0106. Why?

GM's 2008 and 2011 tables for the 3.6L LLT do not list P0106. Air problems on that engine usually show up as MAF, fuel trim or P1101 codes instead.

Can a vacuum leak set P0106 on a GMC?

Yes. Since 2007 the test compares measured MAP with values calculated from the MAF and throttle, so a leak or loose manifold can push the reading away from the model.

Is there extended coverage for P0106?

We found none. The 2021 MAP sensor service update covered dealer inventory only and expired May 31, 2022. GM's valve spring PI references Powertrain coverage, which depends on your truck's age and mileage. A dealer can check your VIN.