When was the last time you changed the fuel filters? Maybe there some water in the main (can) filter causing you problems. Also, maybe its the fuel itself? Are you burning standard diesel or bio? Adding any anti-gel to it? I use the power service white bottle in the winter - it helps disperse water, stops gelling and adds a few cetane numbers too. Sounds to me like you have a fuel issue based upon what you have already done.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz