S60 2.5T Hard Starter Unless

[icecold40]

I have a 2006 S60 2.5T that is hard starting unless you put slight pressure on the gas pedal
If I push just the slightest amount down on pedal it will start right up
When the car is cold and I try to start with no pressure on pedal, it will start, stall, start, stall
but if I put a slight pressure on pedal it will start right up. It's almost acting like the old carbureted motors.
The car has 200K miles and my suspicion is the Throttle Position Sensor thinking that much use
on that sensor has it slightly worn out.
Am I totally out of it on this one or am I close to a solution

[RickHaleParker]

Best bet is the Electronic Throttle Module (ETM) is dirty and needs cleaning, debris in the ETM is choking the engine when the butterfly at it's minimum. This is evidenced by the fact that when you give it a little air it starts.

Another possibility is the MAF is dirty and not correctly detecting the air flow. I would start with cleaning the MAF sensor because it is a 5 minute job ... if you have the correct security bits and a can of MAF cleaner.

[icecold40]

Couple of questions:
Where is the ETM and can I clean it and how
the MAF was replaced 1 1/2 months ago and was cleaned recently as a precautionary measure

[RickHaleParker]

Underside of the intake manifold. Spray Carb cleaner on a rag, prop open butterfly, wipe inside clean.

Part 1


Part 2

[mrbrian200]

The 2006 uses the Bosch style throttle body. You can try cleaning it, but from my experience and your description of the problem there's a good chance you'll probably end up replacing it. Either the integrated TPS is bad, or the internal mechanism that opens the throttle plate is worn out. Pressing the pedal down commands the throttle plate to open further overpowering physical sticking that is keeping it from opening the normal opening (smaller amount) during startup.

Also connect it to an OBD diagnostic and make sure the coolant temperature sensor is giving a proper reading for the actual engine temperature. If it's reading hot when it's not you'll usually see cold start issues. But from your description/symptoms my money's on the throttle body.

My bit of advice, if you end up replacing the throttle body I would probably recommend the xemodex 'upgraded' unit where they've modified these with a contactless throttle position sensor. PN VO.1020.30711554H.00.20 If you buy one from Volvo/Bosch you'll get one with TPS that uses a set of mechanical sweeps like the original.