Newbie needs help 1990 7.3 idi e4od

[Fishermansteve]

I have a 1990 F250 with the 7.3 IDI E4OD Trans. Problem. ..no tach , only 2 gears, od light staying on ( dim ) speedometer intermediary acts up. I am totally new to Deisel engines . Only thing I have been able to check is the fuse under the dash. Where do I start ???

 

[quickster]

sounds like truck is in limp mode. try the tach sensor first. to the right of the oil fill. use the search here. this site can tell you everything. type in limp mode and see what you get. good luck

 

[trackspeeder]

Check the TCM relay under the hood. (Driver side fender)

A dim OD OFF light indicates no power to the TCM.

 

[icanfixall]

Both above suggestions are best places to start looking.