Volvo 940 se turbo estate 1995 engine cuts out whilst driving will restart in minutes have renewed fuel filter ignition switch fuel pressure ok will be ok for a while then fault returns

The engine is not designed to run without the turbo. Fuel pump recirculates fuel to the tank to control pressure while driving and engine is running so poorly fuel is being diluted. Fix the turbo.

could be the fuel pressure regulator. Could be clogged vacuum lines as well.

Check ground wires.

check the large relay in the fuse box and push it down it works a number things

I am a volvo tech and your problem is fuel pressure ralated and i had same problem in 1995 850 turbo and the fuel pump was the problem and a used one is around 35.00

Check the turbo waste-gate actuator spring for proper tension.

Check the fuel pump relay (white inside and back of fuse area behind the cig ashtray). They get old and quit.

Second, check frayed wires on the crank angle sender - they could be grounding out on the rear of the engine.

Perform a check on the ECT switch (toward rear of head under the intake manifold (hidden over the oil trap). It's a nuckel buster to remove, and ou don't want to break it.

Also check spark plugs for wear and gap. Check coil wire, and plug wires for jumping spark.

Have you checked compression on non firing cylinders? Likely has blown head gasket between these two cylinders if located side by side.

crank sensor problem

on the engine drivers side below the air intake/below the brake fluid reservoir/ follow the large red batery cable