Hi all, well my 2.0T 1999 S40 is still not starting right and is getting worse. When I try and start it the engine starts but cuts out unless I give it some gas and even then sometimes when I take my foot off the pedal the revs drop and it cuts out. It seems to run ok after I drive off but just doesn't start properly, oh and after it starts it smells of gas. I've replaced the Fuel pressure regulator and spark plugs, but they didn't help. Unfortunately here in the UK nowhere reads codes for free so don't know if there's any but non of the warning lights are on, once when it didn't start the lambda light came on and stayed on until I started it up again.

Thanks Nick

 

You might have a bad ECT sensor.

 

Is it easy to replace? Im not sure where about it is.

Thanks Nick

 

The ECT sensor is on the front of the motor. If you follow the upper radiator hose to the motor it is in the front aluminum part.

You might also want to do the thermostat. It is easy to replace the sensor with the top of the thermostat housing off. So if you are in there you might want to do both.

 

I've replaced the ECT sensor today and it starts from cold perfect now and the revs are fine which is great thanks, only problem now is it doesnt start every time when warm. When ive been driving and turn it off when I start it again not long after sometimes it doesnt start without a bit of gas. Ive noticed that if I unscrew the fuel cap and put it back on it starts perfect. What could this be?

 

Something in the evap system might be bad.
Have you checked the fuel pressure regulator to make sure that isn't leaking?

 

I replaced the FPR with a new one from volvo but dont know how to test it?

 

The if you already replaced it then I would not worry about it.

Did you ever get the codes reset?

 

No I was told it would cost £50-100 ($100-200) to do, the warning lights do come on and go off ok dont know if that means anything. Can the ECU be reset by disconnecting the battery for a while? and would that clear any codes?

 

You can try that but also remember you will need your radio code.

Best would be to find someone that can reset the codes. Some Non-Dealers can reset them.

 

Ok I will try resetting the ECU first, what could be wrong with the evap system?

 

There might be a valve not working properly.
But that might be because there is still codes stored in the ECU. Thats why you need to reset the ECU first.

 

Well on Sunday I reset the ECU and it started great every time and ran really well until today. I went to start it and it wouldn't start, then after a few times it started badly and the lambda symbol on the dash is on all the time now, it struggled to pull off, the engine seemed hesitant. Got down the road and it wouldn't pull off from the junction then it accelerated on its own and pulled out without my foot on the gas! Now it really struggles to start every time and is un-drivable. What could be wrong? What does the lambda symbol on the display mean?

 

That Lamba signal means there is now codes stored in the computer. You need to have the codes read to tell you what is going on.

 

Just an update, took the car into volvo for a diagnostic, they read the codes and they were contradictory and just there because it failed to start. They cleared them and tested all the sensors (inc lambda) everything was fine so they cleaned my throttle body and idle control valve which was full of gunk and now its great. They said if it happens again it could be my RPM sensor or I need a new idle control valve. Thanks for the help tech.

 

hi rickrarey, im new to this volvo stuff but i have a code reader but i live in aberdeenshire,