crazy gauges on 1998 12 valve

[josh89]

hey guys i was wondering if anyone out there has had this same problem. I bought the truck a few months back with no issues present besides having a dirty fuel filter. I changed the filter and it ran fine. Fast forward to this month. I start the truck up one morning and drive it down the block. I notice my tach jumping very rapidly. The truck drives and shifts fine but the tach is violently bouncing around from 1,000 to 4,000 and back with no real pattern. After this happened i noticed my fuel gauge fall from practically full to empty. I knew this was not correct because i had filled the truck up the night before. The fuel gauge has since been very unpredictable. Sometimes it will read correctly and sometimes it reads completely full. Other times it reads completely empty. I have no clue as to what is going on with this truck. Yesterday i was driving and it was shifting fine. Once i got up around 55 mph or so and let off and tried to get back on it felt like the tranny was slipping almost. Has anyone ever experienced this before? The truck is an early 1998 12 valve with an automatic tranny. Any help would be great.

[Btp 2332]

Havent had this problem yet with mine, hopefully someone will chim in who has. Bump it to the top for ya :thumbsup

[Racer9]

Probably the ESS, engine speed sensor. Down by the balancer on the front of the motor. It should be about a playing card thickness from the balancer. Also check the wires leading to it, they can be worn through around the water pump.
Fuel gauge is a common problem, the sending unit's aren't very reliable.

[josh89]

thanks for the response. would the ess throw off the tranny? This truck hasnt really been beat on at least since ive had it...and its shifted fine the last few months. I hauled some round bales a week ago and the tranny didnt skip a beat. Now all of the sudden it shifts but sometimes is rough and almost feels like its slipping. Between the weird tach and the bouncing fuel gauge it just seems to weird to have all of this happen at once. Seems like something electrical to me such as a sensor.