F60 TLR 2009 hard to start and stalls during the Idle Speed Control test on YDS

[men7mdck]

Hi forum.....i'm hopping one of you guys will be able to help.

My tender runs two F60 TLR (2009) and both engines are progressively getting harder to start. Once started though they run smoothly at revs and idle. To note, when i hook it up to YDS and activate the ISC test it stalls the engine. What should I look at?

I have changed the ISC, spark plugs, changed the fuel, checked the fuel pump, changed the fuel filters, checked the valve clearances and all sensors are normal according to YDS.

Thanks
Matt

[99yam40]

fuel rail pressure in spec?
did you drain and or clean the VST ?
does the intake manifold pressure reading match weather station info on atmospheric pressure when you just turn the key to the on position?

Just some thoughts