The MAP sensor circuit is out of range — the ECU has no reliable load reading.
P0105 — also written PO1O5, P 0105, 0105 — is the OBD-II code for manifold absolute pressure (map) circuit malfunction. Same code, same fix: this page covers every spelling of it.
The brain of the car has lost its sense of touch; it can't tell how hard the engine is breathing, usually because the sensor is gunked up or a wire has frayed. Very common on Vauxhall CDTi and older Fiat Multijet engines.
P0105 is a sensors fault code, typically costing £40–£260 to put right in a UK garage.
What P0105 actually feels like to drive
- The car feels like it's dragging an anchor when you try to overtake.
- Idle is all over the shop, jumping up and down like a yoyo at traffic lights.
- Black smoke out the back when you bury your foot, especially on diesels.
- It 'kangaroos' or jerks violently if you lift off the throttle suddenly.
- Engine Management Light (EML) is on, sometimes with 'Service ESP' on Vauxhalls.
What causes P0105?
- Failed MAP sensor
- Blocked MAP vacuum port
- Wiring or connector fault
- Split intake vacuum hose
UK vehicles that throw P0105 most often
- Vauxhall Corsa D/E 1.3 CDTi (2006-2018)
- Fiat 500 1.2 8v (2008-2020)
- Vauxhall Astra J 1.7 CDTi (A17DTR engine)
- Ford Transit Connect 1.8 TDCi (2002-2013)
- Honda Civic 2.2 i-CTDi (N22A engine)
How P0105 is fixed
- Replace MAP sensor
- Clear the MAP port with carb cleaner
- Repair vacuum leaks
- Repair loom
The P0105 misdiagnosis that wastes money
I see it all the time—lads rushing to buy a new MAP sensor the second they see this code. They spend £80 on a Bosch unit, swap it, and the light stays on. Half the time on these older Corsas and Astras, the sensor is fine but the tiny vacuum port on the manifold is absolutely choked with black carbon and oil. The sensor literally can't 'see' the pressure. I've also seen people replace the sensor when the real culprit was a tiny split in the vacuum line tucked under the engine cover where you can’t see it.
What a UK garage should charge for P0105
A mobile diagnostic will set you back £50-£80 just to read the code. If it’s just a blocked port, I’d charge an hour’s labour (£60-£90) to clean it out. A new sensor from a factor like Euro Car Parts or GSF will be £40 for a budget one, or £90 for a proper Bosch/Denso unit. If you go to a main dealer, you're looking at £250+ once they add their 'diagnostic fee' and 100% markup on the part. Keep it simple: stick to an independent and ask for an OEM-quality sensor.
P0105 repair cost in the UK
Most P0105 repairs land between £40–£260 including parts and labour. The spread is wide because the cheap fix (a sensor, a hose, a leak) and the expensive fix (a major component) throw the same code — which is why a proper diagnosis before parts are bought saves the most money.
Bob's tip on P0105
Before you let a garage sell you a new sensor, ask them to 'check the live data for the MAP reading with the ignition on but the engine off.' At sea level here in the UK, it should read about 100 kPa (atmospheric pressure). If it reads that, the sensor is likely okay and you've got a wiring or vacuum leak issue instead. Also, insist they check the connector pins for 'green death' (corrosion)—a common UK salt-air problem that causes high resistance and triggers P0105 for no reason.
Can you drive with P0105?
Yes but performance and MPG will drop.
Urgency: medium.