OT - Volvo V70 starting when hot
Turbo Mini Forums

Guys,

Totally OT but figured you're better clued up than 99% of car forums and if I remember correctly several years back a few of you had V70s as tow cars.

Mines developed an odd problem which only seems to occur in cold weather, basically it does like starting when the engine is warm, starts fine if the engine is cold, but if I go to the shops and haven't let the engine totally cool it won't start, it'll turn over fine but there's no sign of life what so ever, not even trying to start. Any ideas? other than sitting in the car wait a hour for it to cool down, which is pretty much the response time of any of the breakdown services, so it works fine when they eventually arrive. I'm guessing it's a temperature sensor of some sort but I'd rather not do a random parts swapping exercise in the off chance that it works.

Cheers

Rob

What engine is it as I am a apprentice at a Ford an Volvo main dealer I can ask the mts

Don't go to to the shops rob, get fit and jog there lol

Coolent temp sensor, goosed and or loose wire to it

Rob,
Even if the car is running again it most likely will have stored a fault code.
Might be worth checking this.

It is known that a faulty temp sensor (or bad connection!) can cause flooding.
Possibly something you can see in wet spark plugs..(?)
This is in the 5-cyl Volvos.

Good luck,
Han

Dazed and Confused....

un plug the temp sensor and try a cold start, dont quote me but i think if the sensor is unplugged the signal the ecu will get is of a high temp ( even though its cold )

if it fails to start as if it would when hot it could be the sensor

i had to change the thermostat and temp sensor on mine but mine was the other way on, would not get hot and was chewing fuel

Yes i moved to the darkside

Instagram @jdm_brett

Thanks guys, that's greatly appreciated, will have a look at the temp sensor.

The engine is the classic 2.5l 20v naturally aspirated straight five.

The sound of the NA 5 cylinder, mmm, nice.
I loved my 850 20V...

Good luck solving your problem,
Han

Dazed and Confused....

Measure the resistance of the temperature sender when cold and when hot. Unless Volvo do it differently to most other manufacturers, it will most likely be an NTC (negative temperature coefficient) sender so should be several thousand ohms when cold and a few hundered ohms when hot. If you google hard enough you may be able to find the actual temperature/resistance tables for the actual sensor installed for a more detailed analysis.

Schrödinger's cat - so which one am I ???