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Discussion Starter #1
whilst driving this morning my cars oil pressure fell to zero and alternator light came on. The engine runs normally.
I have checked all the fuses which are fine, any ideas?
 

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Both the oil pressure sensor and the alternator are on the lower engine wiring harness, which is prone to failure in 119 motors of 1993 to 1995. You don't mention the model year of your car.
 

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Hi Deanyel thanks, the car is a 1995, any idea of the way the harness fails? if I strip back the harness and is the failure easy to see?
 

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Hi Deanyel thanks, the car is a 1995, any idea of the way the harness fails? if I strip back the harness and is the failure easy to see?[/QUOT

The casing for the wires degrades and crumbles ,which is hard to spot and the wires short out which Ive read on here,this can happen anywhere on the harness and its recommended that the engine harness is replaced,search engine harness and you will see what problems it causes :thumbsup:
 

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Indeed, crumbling insulation, but only on the small sensor and ground wires, not on the big wires to the starter and alternator, which makes it a pretty easy harness to rebuild. There's only about 4-5 wires that have gone bad.
 

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Discussion Starter #6
Thanks for the advise, i have had a look and there are some bare wires!! the next job is to trace where they go to and pull new ones
 

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They all go to the same place. I've always taken the whole harness off and rebuilt or replaced it. That would be slick if you can just pull some new wires individually on the car. Let us know how it goes.
 

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Discussion Starter #8
i found that the wires from the alternator and pressure switch had lost there insulation and were touching, fortunately the problem didn't go too far into the loom/harness, I replaced the wires and the alternator and oil pressure gauges work. Now to find the sender for the oil level any idea where it is?
 

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Most likely the problem goes up further than you can see but if you don't disturb it you may be OK. The oil level sensor on a 119 motor is accessed by removing the lower oil pan. The wire is on that harness and goes through the upper pan? probably to get to the sensor. It's in that same vicinity, right side of the engine.
 

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Discussion Starter #10
thanks for the info, I saw the outlet from the pan, the wires look fine so... I guess another job for next weekend
 

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I wonder if they didn't use biodegradeable insulation on that wire because it was going into the engine, hard to say.
 
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