[walt501]

Question from a diesel noob - once in a while when I turn the ignition on to warm the glow plugs my truck makes a humming/vibrating sound from the engine compartment. It only does it one out of say 50 start-ups. Anyone know what this sound is? Truck starts fine with or without the noise. Thanks, appreciate the knowledge on this site!

 

[GrampyJim]

Check to see if it sounds like it coming from the right side (passengers) fender... most likely culprit is the vacuum pump building up to capacity.

 

[abartoe]

I am assuming it is probably the vaccuum pump.

I get something similar it is almost like the truck is farting by the abs module, but not always.

 

[kwazyca]

[ QUOTE ]
Question from a diesel noob - once in a while when I turn the ignition on to warm the glow plugs my truck makes a humming/vibrating sound from the engine compartment. It only does it one out of say 50 start-ups. Anyone know what this sound is? Truck starts fine with or without the noise. Thanks, appreciate the knowledge on this site!

[/ QUOTE ]

Mine does it too.

Vacuum pump.

Tom

 

[Lambert]

Mine does it also but I noticed that the frequency and duration of the sound increased after I put the edge evolution program in. Go figure.

 

[walt501]

Thanks all for your help. I didn't think it was anything to serious, but thought I would check. I'll listen for the vac pump next time it makes the noise.

PS- traded a Suburban for the 7.3 Ex. Haven't enjoyed a truck this much in 20 years! Thanks Ford and KTP employees!