[chadepperson99]

The oil pressure gauge quit working the other day on my 2000 Mariah 258 needing a little assistance. So far I've tried using an ohm meter, on the sending unit got a 1.5 reading with the engine off, and couldn't get a reading with it running. So I'm thinkin maybe a bad sending unit? I was wanting to check the gauge but I have no idea how to get to it, I assume they have two nuts on the back holding them on and I see no way coming under the bottom to get to them, thanks for any help and suggestions!

[Brewfixer]

Just ground the wire from the sending unit and watch the gauge. If the gauge travels full scale, chances are the gauge is fine and your sending unit is the culprit. This is the quick check method. My experience is that most of the time it is the sending unit at fault as the analog gauges are fairly bullet proof.

Good luck

[chadepperson99]

I'll give that a try, does the key just need to be on or does the motor need to be running? Thanks

[chadepperson99]

Well tried hooking a wire up to the blue and grounding it, with both the key on and again with the engine running, gauge didn't even twitch, I'm guessing bad gauge now, anyone have any, tips or tricks on removing the gauge?

[mikeyt]

I'm leaning towards a bad connection (like a ground wire) causing the problem. As Brewfixer says, those gauges are almost bullet proof and seldom fail. Pull connections, clean & reconnect at the gauge, the fuse panel and the grounding block.

[chadepperson99]

Originally Posted by mikeyt

I'm leaning towards a bad connection (like a ground wire) causing the problem. As Brewfixer says, those gauges are almost bullet proof and seldom fail. Pull connections, clean & reconnect at the gauge, the fuse panel and the grounding block.

Any tips or tricks for pulling the gauge, I really can't see how to do it, as far as the fuse panel won't all the gauges quit working,? As far as the grounding block where is that located, sorry for all the questions I'm new to this and trying to educate myself.

[mikeyt]

No, each gauge is wired independently. Usually the access to the fuse panel is from up underneath the drivers console but many Mariah's also have a flip up cushion in the bow area just in front of the drivers console that allows access to the back of the gauge panel.

There is a grounding block on the rear transom wall usually on the driver's side behind where the battery sits.

PS: And check the connections of the small wires that are attached to your battery.

[chadepperson99]

Originally Posted by mikeyt

No, each gauge is wired independently. Usually the access to the fuse panel is from up under neath the drivers console but many Mariah's also have a flip up cushion in the bow area just in front of the drivers console that allows access to the back of the gauge panel.

There is a grounding block on the rear transom wall usually on the driver's side behind where the battery sits.

Yep my fuse panel is right under the steering wheel, I'll try cleaning the connections tomorrows and the same with the block, as for the gauges mine is a cuddy and didn't see any access, unless there is one where the stove sets.