I've done a bit of googling around and haven't found anyone with my set of symptoms, so I figure it's time to ask the experts.
I have a 1999 SLK230 and the fuel gauge works fine at the top and bottom of the tank, but jumps around or pegs up way off range when part-way through a tank of gas. I pulled the sender out, cleaned it up, and confirmed with a DMM that it smoothly reads from 0-200 ohms as you sweep the float through its range. When the sender is unplugged, the gauge reads empty. If I short the pins together going to the gauge, it reads full. I tested putting a set of known resistors across the connector leading to the gauge and everything below 40 ohms registers a predictable value in the empty-1/4 tank range. Everything above 100 ohms registers a predictable value in the 1/2-full range. Anything between 40 and 100 ohms causes the gauge to freak out.
Any good ideas?
Thanks in advance!
I have a 1999 SLK230 and the fuel gauge works fine at the top and bottom of the tank, but jumps around or pegs up way off range when part-way through a tank of gas. I pulled the sender out, cleaned it up, and confirmed with a DMM that it smoothly reads from 0-200 ohms as you sweep the float through its range. When the sender is unplugged, the gauge reads empty. If I short the pins together going to the gauge, it reads full. I tested putting a set of known resistors across the connector leading to the gauge and everything below 40 ohms registers a predictable value in the empty-1/4 tank range. Everything above 100 ohms registers a predictable value in the 1/2-full range. Anything between 40 and 100 ohms causes the gauge to freak out.
Any good ideas?
Thanks in advance!