Main instruments work intermittently
The speedo, fuel guage and temp guage all do not work when I start the engine, then they start working
sometimes, after I have been driving for a while.
The rev counter works fine all the time.
Is it a lose connection or is something on the blink?
The tach will always work because it's a mechanical gauge requiring no electricity to operate. The speedo should work also because it simply measures wheel speed through mechanical means. A sticky thermostat could be whats messing with your Temp. gauge. Once the engine is heating up the coolant in the rad system (by pressure) will pop the thermostat open. Honestly, it seems like your Merc just needs a good once over and tune up. Start there if you're one to let maintenance take the passenger seat ; )
there are alot of commonalities between the components, most common is the connections behind the cluster coming loose, and as you hit a bump, or it just right, it makes contact., let me know if it was it, or you want more suggestions
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