The oil level sender and the oil pressure sensor both have that style connector. I assume your gauge works since you didn't mention anything about it, check that the sender in the sump is connected.

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The oil pressure gauge does not actually work on the cluster. It is always pinned at 3, so this could possibly fix it. Would the oil pressure gauge connection be somewhere near the area of the oil filter?
Thank you

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1991 Mercedes-Benz 190e 2.6- FOR SALE
1998 Audi A4 1.8T

OP should be pinned at 3 until it is totally warmed up. Honestly there are a handful of connectors on the engine that use this boot/connector. Also, to answer your question the engine temp sensor is different than the coolant temp sensor...the engine temp sensor goes to the FI computer and assesses whether or not the engine is warm & to use the O2 or MAPS, the coolant temp sensor goes to your gauge. I might have that mixed up

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth