Weekend Coupe Project - VDO oil pressure gauge (archive)

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About a month ago, I purchased a VDO oil pressure gauge and sender from JonM at LeatherZ and an A-pillar pod from egauges.com (you can get the pod from Jon too but he happened to be out when I ordered). I took the A-pillar cover off a couple of weeks ago and cut the hole in it for the gauge. Finally got around to the rest of the job this weekend.

I took care of the wiring and gauge first (inside), then the sender (under hood). You need 4 wires for the gauge. One for power, one for ground, one for dimming, and one that goes up to the new sender (the dimming power wire allows the new gauge to be controlled by the instrument dimming control). The ends are terminated with push-on connectors that fit onto the back of the gauge. The wires are run from the A-pillar down into the footwell area, where the ground is connected to the grounding nut (behind the side panel with the dead pedal), the power wire taps into to any violet/X wire and the dimmer wire taps into any gray/red wire.

The sender wire goes through the firewall (which puts it into the fuse box), back out of the fuse box, then forward to where the oil filter is. You replace the original sender on the filter housing (which gives you the "idiot light" for oil) with a new sender which gives you both the idiot light and pressure. The original wire and the new sender wire are terminated with crimp-on o-connectors to connect to the new sender.

Of course before you mess with the sender you have to drain the oil, so this was an opportune time to do an oil change. Used the Pela Oil Extractor which worked really well.

This was probably the toughest project we've done to date, primarily because it entailed both interior and engine changes. Opening the fuse box in the engine comparment to run the sender wire was a bit daunting but like other things once you've done it it's not too bad. I was very happy to see the gauge work correctly, and no oil leaks when we took the coupe for a test ride.

Thanks go to JonM for the instructions he sent and to Ron Stygar for his help real-time and from previous posts.

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