Volvo Repair: volvo v40 t4. wont start from warm, water temp guage, volvo v40 t4

Question
Hi there. I've had a volvo v40 t4(2000 reg) for 6 months. It's got 65000 miles on and has never missed a beat. The other day was red hot outside. I drove for 25 miles, park it up for 2 hours. Came back to it and would not start straight away. If you keep pumping the throttle it will eventually start, but the idle stays at 2000 revs and kicks abit of smoke out the exhaust when revved as if it's over fuelling. I have noticed that the water temp guage is reading very hot even though the car has been stood for around 2  hours. Could it be a faulty temp sensor?

Answer
It very well could be.  The ECT adjusts fuel for the cold start or hot start and if its been sitting it should be no hotter than 1/4-1/2 gauge reading at startup.  You can only be sure though if you read off the diagnostic trouble codes looking for an ect fault code.  They will ALWAYS set with an ECT failure.  Any shop should be able to do that for you.  Also if you do have to replace the ECT besure to replace the thermostat at the same time.  It is very cheap insurance and it is all in the same location.  The type of problem could be caused by alot of things but check the ECT first since you noticed a problem there.  The shop that does the computer readoff should be able to tell you if there is anything else going on there that may suggest a different problem.

James