'97 , 6.5 no power, SES light off and on

[Bobby Williams]

I have a 97 dually service truck. For the last 2 or 3 years the power output is off and on. When it is off the SES light is on. The PMD seems good, replaced turbo boost sensor, connectors, ect. It has 273,000 and I'm trying to get 300,000 out of it so I can retire without having to buy another truck. I'm in central N.C. if that matters. Thanks.

 

[snarl95]

Have you pulled the codes?

 

[JMJNet]

Welcome!!!

Check the code.

This is my suspicion.
Check the vacuum hoses that attach the vacuum pump to the Turbo Solenoid to the Turbo?
It may look good but you just have to touch them, they usually crumble and needs replacing due to age.

 

[GM Guy]

welcome to the site!

Get a notepad and head on down to any of the chain auto parts stores. I dont like much if any of their parts, but they do check codes for free.

If you have any other 1996+ vehicles, consider getting the cheapie 40 dollar code reader from Harbor freight, it is a decent basic reader.

Codes will greatly help in the diagnosis. It could be vaccum controlled boost related, or something totally different.

Have you checked fuel pressure?

 

[Garymac]

Check to see if vacuum pump is holding at waste gate and or gate is closing properly?