1994 runs ruff 157 158 335 codes

[Mikey Machine rvellone]

High voltage 4.12v from maf sens ,no reading from egr vac sensor CODES 157 158 335 ,need direction on wire diagram, back probe wire harness for grounds, and typical voltage readings on sensor connections egr vac , air vane temp , tps ect,i no longer have access to mitchel on demand. truck runs ruff stalls , seams to have miss on #4 cyl may be separate issue. no misfire codes. i just registered this morning as member .

 

[telsar]

Look on BBB Industries tech info and see if they have your wiring diagrams:

https://www.bbbind.com/

 

[Mikey Machine rvellone]

Found it Thank you ,Now for the back probe and continuity testing, I will start with grounds , then power reference .