Powertrain, generic (extended)

P2091 "B" Camshaft Position Actuator Control Circuit High (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2091 says the control circuit of actuator B on bank 1, normally the exhaust phaser valve, sits too high. GM's high-side version on the 3.6 L LFX checks for a short to supply while the output is off and, like P2090, treats it as Type A after 20 of 25 samples; 18OBDG02 uses Type B. On the low-side controller of table 23OBDG07 the same code means the pin stays at supply voltage even though the driver should be pulling it to ground, and it takes about 1 s to confirm, two trips for the lamp. Ford shows P2091 in its 2014 petrol code list as a lamp code that both key-on and running self-tests can find. A short of this kind can overheat the driver, so the ECM usually switches the output off and leaves the exhaust cam at its default angle. Out-of-range timing of the same cam is P0014 or P0015.

Likely causes

Exhaust valve control wire touching a supply wire
Incorrect splice or pin swap after earlier wiring repair
Failed output stage in the ECM

Symptoms

  • Engine warning lamp on
  • Exhaust cam stays at default angle, slightly reduced performance

Repair estimate

DifficultyMediumDIY possible
Parts and labour€30–350
Time0.3–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

oil control valve exhaust bank1oil control valve wiringengine control module

Related codes

P2090P2089P2095P0013P0014P0015

References: gsi.ext.gm.com, gsi.ext.gm.com, performanceparts.ford.com.