Powertrain, generic · Fuel and air metering (injector circuit)
P025E Turbocharger/Supercharger Boost Sensor A Intermittent/Erratic
Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible
Boost sensor A measures the pressure between charge air cooler and throttle (Ford TIP, GM TIAP). P025E counts brief excursions outside its valid voltage range that are each too short for the low or high code P0237/P0238 – Ford's limits are below 0.19 V and above 4.88 V. Ford counts these events continuously and sets P025E after 10 in one drive cycle. Boost control then runs on a substitute value or is switched off, leaving only base boost. Typical causes are a loose or corroded connector or a wire breaking under vibration and heat.
Likely causes
Loose contact or corrosion at the sensor connector
Wire or 5 V reference breaking from vibration or heat
Sensor faulty internally (erratic signal)
Shared 5 V reference disturbed by another sensor
Symptoms
- Check engine light on
- Occasional loss of power, boost limited
- Jerking on acceleration
Repair estimate
DifficultyEasyDIY possible
Parts and labour€30–200
Time0.3–1.5 h
Typical range across vehicles; the real cost depends on what the testing finds.
Parts involved
boost pressure sensor asensor wiring
Related codes
References: law.cornell.edu, fordservicecontent.com, newtonnet.co.uk.