MPG Gauge

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CarBot
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PSU_Crash wrote: All other gauges work as they should 100% of the time, aside from occasional jitters in the oil pressure gauge.
If everything else is solid and only the MPG gauge is acting up, that points away from a general cluster power feed problem and more toward either the MPG gauge itself, its local connections/solder joints, or the specific signal it uses for “fuel flow.”

The oil pressure gauge jitter is pretty common on these and is often sender-related or just a slightly noisy connection, so I wouldn’t automatically tie that to the MPG issue unless you also see other electrical oddities like dimming lights or multiple gauges twitching together.

Given your “tap the brake and it comes back” clue, I’d still put my money on an intermittent connection rather than a failed gauge movement. The most productive next step is to pull the instrument cluster and do a careful inspect/reseat. Look for any looseness or corrosion on the multi-pin connectors, and inspect the solder joints on the MPG gauge and the cluster board for hairline cracks (they can look fine until you flex the board slightly). Reflowing suspect joints often fixes intermittent behavior.

If you want one quick test before pulling the cluster: next time it’s pegged high, turn on headlights and rear defrost (big electrical loads) and see if the MPG gauge changes behavior like it does with the brake tap. If loads affect it, that’s another hint you’ve got a marginal ground or connection feeding that gauge.

If you can share whether it ever pegs low, or if it only fails by pegging high, that also helps. Pegged high specifically tends to mean “no injector signal seen” rather than “no speed signal,” assuming the car is moving normally.

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PSU_Crash
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Thanks @CarBot !
I'll try to turn on some loads the next time I'm out driving.
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PSU_Crash wrote: Thanks !
I'll try to turn on some loads the next time I'm out driving.
Sounds good. If electrical loads make it wake up or change reading, I’d focus on a marginal ground or connector in the cluster/dash area. If loads don’t change anything but bumps or brake pedal movement do, I’d focus more on a flaky connector or cracked solder joint at the MPG gauge/cluster board.

When you get a chance, also note whether it comes back only while the brake lights are actually on, or if it comes back just from the pedal movement even with a super light tap. That detail can help separate “electrical load effect” from “mechanical jiggle effect.”

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