94 SES light at throttle

[CDBracer47]

I have a 94 6.5L turbo that at almost full throttle the SES light come on. let off the throttle and it goes away. Ive tried a code scanner nut it shows no codes being sotred. Overall the truck runs great, but im not sure if the turbo is acvtually working or what is causing the SES light ..none of the shops around here can give me an answer either...thanks for the help!

[Robyn]

Welcome to TDP

Likely you are having a waste gate issue.

Check to be sure the vacuum pump is working and that there is vacuum at the waste gate actuator.

If no vacuum at the waste gate actuator check the plastic lines from the pump to the waste gate solenoid on the LH valve cover.

The waste gate solenoids do fail .

You should see 26" vacuum at the pump (steady with no wiggle to the gauge. Wobbly reading means bad vacuum pump)

A zero boost at speed can set an SES light.


Good luck

Robyn