HELLO, I purchased a 2000 s40 1.9T for the couple days i have had the car I like it BUT some times after driving the car 20 min. to hours, with no problems. Then will park it for 20 min. or so try to restart and it just turns over and over. the one thing i have noticed is with key in on position temp gage is pegged. After the car has set for hour or so I turn key to start position temp gage is down low as should be and car then starts.. Ran all day with no problems, with temp gage at middle to low. yet once shut off and 5 min. later gage says pegged and wont start.. OH the kicker is the cooling fan wont shut off even with key out runs battery down eventually

So only code 118 temp sensor.. Guess i am wondering will temp. sensor do that?? keep fan going and make it not start??? getting fuel , seems to shut spark off. it has 150 thousand on it and everything in eng. bay and under car look very very good. And car was well maintained Do I start changeing sensors?? Runs great with normal temp till shut offand NOT overheating i can touch exhast its normal temp. no boiling over no smoke from tailpipe at all. White or blue..

 

Thank you

 

Sounds like you need a new engine coolant temp sensor. Easy enough to replace (you need to remove the two torx screws holding down the thermostat cover then move the upper hose out of the way. If you want to test the sensor before removing, you can unclip the lead (its the singularly most complex connector I've seen LOL) and use a VOM to measure resistance. Should be under 200-300 ohms with a cold engine... or you can simply replace the sensor ($20 after market, $40 OEM Volvo)

 

Thank you . I replaced sensor and so far so good. No more wondering if I would be sitting while engine to cool.. Still think it was odd that she wouldn't start and fans stayed running with ignition off. learn something new every day. Now a couple of engine/trans mount to calm down the vibration and this s40 should last me awhile.. Thanks again for info. very much appreciated.

 

these cars have a cool down timer so with a false temp reading its telling the fan to stay on (I forget exactly how long the timer is for...) - mine did the same thing until I replaced it. For the tranny mount, look at the one off the front by the passenger side. There should be some prior posts on the board with pics to help.

 

When I replaced my engine mounts the bad ones were the two on the bottom. The trans mount and main engine mount both appeared good. Watch out for the change in style of the main engine mount. The aluminum arm changed which changed the mount itself. You can make it fit with some grinding.... just be aware.