TCC solenoid stuck engaged — causes engine to stall at low speed.
P0742 — also written PO742, P 0742, 0742 — is the OBD-II code for torque converter clutch stuck on. Same code, same fix: this page covers every spelling of it.
This code means your automatic gearbox is 'staying in gear' when you stop, acting like a manual car when you don't use the clutch. It's a common headache on Vauxhall Insignias and older Volvos.
P0742 is a transmission fault code, typically costing £200–£900 to put right in a UK garage.
What P0742 actually feels like to drive
- Engine stalls every single time you come to a stop at a roundabout or red light.
- The car 'lurches' or shudders violently just as you're slowing down to a crawl.
- Feels like the car is 'fighting' the brakes when you're trying to stop.
- A noticeable drop in fuel economy because the lock-up is fighting the engine at the wrong times.
- Hard shifting or a 'thud' when the car finally manages to disengage coming to a halt.
What causes P0742?
- Stuck solenoid
- Contaminated ATF
UK vehicles that throw P0742 most often
- Vauxhall Insignia 2.0 CDTi (AF40 Transmission) 2008-2015
- Volvo V70/S60 2.4 D5 (Geartronic) 2005-2012
- Ford Mondeo Mk4 2.0 TDCi (Aisin Warner AW21) 2007-2014
- Saab 9-3 1.9 TiD (AF40 Transmission) 2004-2011
- Land Rover Freelander 2 2.2 TD4 (Aisin AWF21) 2006-2014
How P0742 is fixed
- ATF service
- Replace TCC solenoid
The P0742 misdiagnosis that wastes money
I've seen so many lads jump straight to 'gearbox is toast' and quote for a full re-con unit, which scares the customer half to death. They also tend to throw a new crank sensor or throttle body at it because the car is stalling at junctions, thinking it's an engine management issue. Nine times out of ten, it’s just the TCC solenoid gummed up with old, burnt fluid or a bit of debris. Don't let a garage sell you a £2,000 gearbox before they've even dropped the pan to look at the valve body.
What a UK garage should charge for P0742
A basic diagnostic plug-in will run you £50-£80. If it’s just a fluid service and a solenoid clean, you’re looking at £200-£300. However, replacing the TCC solenoid usually involves dropping the transmission pan or side cover; with genuine parts (often Aisin or GM) and fresh ATF, expect a bill between £450 and £600. If you go to a main dealer, they’ll likely refuse the solenoid repair and insist on a full valve body replacement, which north of £1,200 easily.
P0742 repair cost in the UK
Most P0742 repairs land between £200–£900 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 P0742
Before you let anyone tear into the box, ask them to do a 'stall test' and check the live data for the TCC slip rpm. If the car feels like a manual where you've forgotten to dip the clutch when stopping, that's your P0742 right there. Insist on a 'double flush' using high-quality ATF (like Millers or Fuchs) rather than the cheap universal stuff some factors push. If the fluid comes out smelling like burnt toast and looks like Guinness, the damage might be internal, but a solenoid swap often saves the day.
Can you drive with P0742?
Yes but stalling risk.
Urgency: medium.