If a Volvo s40 throws its timing belt does it ruin the engine?

It can sometimes depending on where the valve smacks the piston and what speed you are driving

Your S40, I'm 90% sure, is an interference design, meaning if you don't change the timing belt every 100,000 miles and let it break, yes the engine is damaged. The valves will lock in an"interference position", so when the piston reaches top dead center, it hits the valve. You have a dead engine!

P0015-camshaft position actuator B-Bank 1 timing over - ******.

1.9 ltr right? Engine prone to sludge. Try and engine flush like seafoam (don't drive with it in your engine.... run it for a few minutes then shut it down) then change your oil and filter to a good quality synthetic. Then clear the code. Won't hurt it if you drive it with this code but can be annoying.

I have an owners manual in PDF that i can send you if you want. Email me at [email protected] with your make, model & year and i will be happy to email you a copy. I may have a service or haynes manual on PDF fomat as well but will need to make sure. If you email me for the owners manual if i do have the service manual i will send that as well just remind me to look. Have a great day.

The 1.9 Liter has a cam belt which MUST be replaced at 105,000 miles. Also replace the water pump which is driven by the cam belt to save labor costs later one. This is an INTERFERENCE engine and as such if the belt breaks you will have serious engine damage. Therefore do not neglect this service.

They could have been incorrectly fitted not to factory spec so they disintegrated this may be due to you went with cheapest place possible.

Click on the following free direct Link. It has the Timing: Belt and Mark Diagrams for your 2001 Volvo S40. Plus additional Instructional and Directional Diagrams.

Let me know if this helped, or if you have additional information or questions. Feel Free to contact me at FixYa.com!

http://www.2carpros.com/car_repair_information/year/2001/make/volvo/model/s40/2001_volvo_s40_timing_belt_diagram_marks.htm

Volvo Radiator, Thermostat and Sensors Your cooling system's temperature controls include all coolant temperature sensors, Volvo thermostat, Volvo radiator or expansion tank cap, cooling fan(s) and fan clutch (if equipped). These cooling system parts function primarily independent of the engine but control the engine either through cooling or by sending control signals to your Volvo's electronic systems.
The Volvo thermostat is a spring-loaded valve that opens and closes based on the temperature of the coolant flowing through it. A high temperature reading followed by a drop to normal temperature (or a continuously low temperature) is a common first sign of a sticking Volvo thermostat. However, many other conditions may cause these symptoms, so you need to know how to eliminate each possibility.
The Volvo radiator or expansion tank cap is also a spring-loaded valve reacting to system pressure. It serves to maintain proper system coolant level at predetermined pressures. It must always be replaced with an exact replacement cap with the same pressure setting. Never use other caps except for short-term emergencies!
A belt-driven fan blade for pulling air through the Volvo radiator is usually on the Volvo water pump pulley and should have a fan clutch to control it. The fan clutch allows the fan to turn with the belt at low engine speed and "free-wheel" at higher speeds. A bad fan clutch either doesn't allow the fan to spin at low speed (overheating in traffic) or doesn't allow it to free-wheel at high speed (potential overheating on highway or reduced gas mileage).
An electric fan can be either by itself (usually front-wheel drive) or auxiliary (used with a mechanical fan). Both types are controlled via a temperature sensor - in the Volvo radiator or upper Volvo radiator hose or on the Volvo thermostat or Volvo water pump housing. This sensor is usually an on/off type switch with a fixed temperature setting. (Some vehicles may have 2-3 settings for multi-speed fans.) This sensor is commonly called an "auxilliary fan switch".
Other common temperature sensors are: 1) gauge sender (variable output); 2) warning light sender (on/off type); 3) lambda and/or fuel injection sensor(s) (variable to control fuel injection settings); 4) thermo-time switch (cold start valve control). Your Volvo may have other sensors as well.
Temperature control is critical to both performance and emission control. Unfortunately, this system is the most difficult to troubleshoot without proper equipment and diagrams. It's even more difficult with computers that adjust timing, idle speed, vacuum and fuel delivery automatically to make up for potentially faulty temperature sensor signals.
Maintenance of your cooling system sensors is virtually impossible since there's nothing really to "maintain". Keeping them clean both internally (coolant replacement) and externally (engine cleaning) is the best way to ensure trouble-free driving. Checking and replacing all parts at the factory-recommended time or mileage limits helps as well

YOU MAY HAVE A IDLE SPEED CONTROL VALVE PROBLEM, CLEAN IT FIRST, THEN DISCONNECT THE BATTERY, FOLLOW THE PROCEDURE I HAVE ATTACHED.

Here is the most common cause of this stall and idle speed issues, it is the idle speed control air-bypass valve and throttle valve, they get full of gunk over the miles and cause idle issues (stalls) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.