Engine/Transmission (1994 - 1998) Hard to start and poor mileage.

[kebees4]

A friend just called and asked why his 1994 Cummins suddenly became hard to start and mileage went from 18-19 down to 2-3 mpg's. I told him I have no idea but would post it here for some help. It has a new fuel filter(2 months old) and this is not driven every day but once in a while. Can anyone point him where to look?

 

[Joe G.]

The timeing has probably slipped.

 

[DBrickel]

Did he check for fuel leaks around the lift pump?

 

[kebees4]

Thanks for the replies. I passed the info on to the owner. He has no leaks and is going to look at his timing.