Surging Steep Grades Uphill Highways Speeds

[RrCoX22]

Vehicle is surging going up steeper grades on the highway, the surging is consistent almost for 3 seconds on/off until a level plane is reached. Not sure if this is fuel related or if anyone else has experienced such an issue. On level grades it doesn't do this at all, runs fine, only steeper inclines. I have not been able to test at lower speeds but don't recall it happening then.

 

[ppc]

Vehicle is surging going up steeper grades on the highway, the surging is consistent almost for 3 seconds on/off until a level plane is reached. Not sure if this is fuel related or if anyone else has experienced such an issue. On level grades it doesn't do this at all, runs fine, only steeper inclines. I have not been able to test at lower speeds but don't recall it happening then.

I would examine very closely the the main engine wiring harness where is passes next to the EGR. The load on the engine causes movement of the harness in that area. There are many threads with details and pictures the damage caused by the heat if you search.

 

[mudgudgeon]

Vehicle is surging

What vehicle?

 

[bhsdriller]

maybe this one in his sig

1994 FZJ80 White Factory 3x Locked

 

[alia176]

also, could the transmission be slipping under extreme loads? The clutch bands could be worn out given the age and mileage.

 

[retlaw]

I experienced similar with a another vehicle. It was a bad fuel filter.

 

[mudgudgeon]

maybe this one in his sig

1994 FZJ80 White Factory 3x Locked

What sig?