90 7.3 second gear and no tac

[smuesse]

I just picked up a 90 F250 7.3 with E4OD. Its stuck in 2nd gear when its in drive, the tach does not work, and the OD light stays on. I can manually put it in first. I have checked all the fuses under the dash and cleaned the wire connector that is on the side of the tranny by the shift linkage. Still no fix. Any suggestions on other things to check. I read something earlier about a tach sensor, i plan to check that but im wondering if there is another fuse or Relay i dont know about.

[smuesse]

I replaced the Tach sensor and it did not fix the problem I started tracing down wires and found a burned fuse link by the passenger battery. I fixed that and all is good. This truck runs so good and is so cheap to maintain, I think im going to sale my 05 6.0 and keep this truck.

[BadF250Boy99]

did your tach completely die? mine on occasion will show its idling around 100-150 rpms when i know its not if i tap the gas pedal it will eventully start reading correct i wonder if this fuse link could be my issue

[smuesse]

No the Tach was Dead because there was no power to the ECM relay. Sounds like you may have a bad tach or Tach sensor. If you need a new sensor ill sale my old one. I replaced it thinking that was the problem.

[Shadowfax]

old thread but for anyone else that finds this I had the same issue, turned out to be the #22 maxi fuse under the hood was blown by the fuel heater. Caused the tach to not work and truck go in limp mode when put in drive.

I replaced the fuse and unplugged the fuel heater and all is good.