Loud noise at idle and off acceleration

[blingn]

Well my diesel did not want to start this morning. I might have added to this buy putting the pedal half down like in my old ford diesel. When it was cold out I would hold the pedal half way down to start it. So I did the same on the new one. Now when I got it started it is making a loud noise at idle and right off idle. It sounds like exhaust. When I let off the acc pedal it is making a loud exhaust noise that it did not make before. It feels and sounds like there is an exhaust break on. I am searching now and have not found the exact problem that I have.

[Bob D]

Mines done it for years, like 5 or so, but only when its really cold. Keep in mind here in Wa really cold is about 25°F. Once it warms its fine. Kinda sounds like you uncapped the headers. Lol

Never worried about it. Figured I had a tiny leak and when its really cold, it leaks more as the metal shrinks. Once it expands, its is fine. Actually now that I think about it. It was about the time the BIG exaust was put on.

[blingn]

Originally Posted by Bob D

Mines done it for years, like 5 or so, but only when its really cold. Keep in mind here in Wa really cold is about 25°F. Once it warms its fine. Kinda sounds like you uncapped the headers. Lol

Never worried about it. Figured I had a tiny leak and when its really cold, it leaks more as the metal shrinks. Once it expands, its is fine. Actually now that I think about it. It was about the time the BIG exaust was put on.

It is cold to california standards 32 F. Newer truck to me and have never heard it before. 96 f250 t/d

[RD97]

It sounds like it's probably the exhaust backpressure valve operating normally.

[blingn]

Originally Posted by RD97

It sounds like it's probably the exhaust backpressure valve operating normally.

not doubting you, just new to diesels, why did I notice it now when it was cold and not before? thanks

[4micaman]

Originally Posted by blingn

not doubting you, just new to diesels, why did I notice it now when it was cold and not before? thanks

Cause that's what the EBPV is designed to do. Close (fully or partially) when the PCM sees oil temps below a certain point. It's to aid in bringing the engine up to a normal operating temperature.

[blingn]

thank you for helping out, sorry for the newby question. I went and started it at break and the truck started right up and ran good with no noise. I am going to let her warm up more tomarrow morning. I am thinking of putting a remote start alarm on it. thanks again.

[4micaman]

Originally Posted by blingn

thank you for helping out, sorry for the newby question. I went and started it at break and the truck started right up and ran good with no noise. I am going to let her warm up more tomarrow morning. I am thinking of putting a remote start alarm on it. thanks again.

No worries. No apologies needed. If your trucks block heater is working, just plug it in an hour before leaving on cold mornings. In cali, that should be more than ample time to prevent the "jet" or "buzzing" sounds the EBPV will do.

The first time mine did it. Scared the crap out of me. All I could see was dollar signs flashing before my eyes!

FWIW, Idling your truck to "warm" the engine will kill your fuel mileage. Besides, kilowatt hours are much cheaper than the fuel you'd burn.