Sorry for the long story, but I'm really desperate for some help so thank you in advance.

I have a 2000 Disco with 140,000 miles on it. Driving it from MN to FL, the temp gauge was rising so we pulled into a repair shop and were told the water pump was leaking. Replaced the water pump.

Then we drove off and within 10 miles the oil light came on. (error code knock sensor) Towed back to the shop, no water in the oil and they pressure tested (so they said) and the pressure was good. We were told that the knock sensor must be triggoring the oil light because all tests were fine. They test drove for 1/2 hour, no oil light. We drove off for about 1 hour and the oil light started flashing and slight tick or knock sound from the engine. Error code said misfire in cylinder 8. We pulled off and the next shop told us we had a bad wire, he fixed the best he could (late in day) and the oil light was off and no tick sound from engine.

We drove another 2 hours with no light and no sound, then the oil light started flashing again and the tick sound was back (a little louder this time) and error code misfire cylinder 8, I pinched the wire again and it drove well for another hour, then started again. This time misfire 8 and 4 and damaging Cat codes came up. We pulled in to another shop, thinking we needed new wires and were told it has no oil pressure (need new oil pump) and they also said there was no way the oil pressure had been tested the previous day.


Question 1) Any ideas whats going on?Iif there was no or low oil pressure why was the oil light coming and going? And why were we able to make it disappear just by reconnecting a bad spark wire?
Question 2) Can the oil pump be damaged when replacing the water pump?

Any help would be greatly appreciated. Im stranded in the middle of nowhere with a new job to start in Florida and don't want to be an out-of-towner being taken advantage of. Thanks

 

Send me your number and I'll call you right back, but hurry cause I am only going to be around for awhile this morning.

 

Answer 1) It sounds like oil pump. Before mine went, it light came on and after I turn the engine off and started again, it was gone (this happened 3 times throughout a 12 month period). Spark wire was just a coincidence I believe. Specially if you heard the knocking......not enough oil pressure to reach the top of the engine. Adding all this up, equals to a new oil pump.

Answer 2) Oil pump is inside front engine cover. It cannot get damaged while replacing water pump.

If they checked the oil pressure and there wasn't any.....sorry fella.

 

Thanks so much for the advice Mike and Boris.

Man I am having one of those nightmares you read about other people having. It has taken me 5 days to drive 12 hours.

 

Let us know how all your up-coming phone calls turn out.

 

I would add that it might be possible to damage the front cover, and possibly the oil pump, when replacing a water pump. The water pump bolts are various lengths, and if the wrong bolt was tightened down in the wrong hole, it could fracture the front cover, not sure if it would touch the oil pump, but it might dump metal trash into it.

 

You can order a oil pump from atlantic british pretty cheap. It sucks to do. Took my disco 1 and I 8 hrs. But I also removed the radiator because I needed room to work and the radiator was shot. If you want, now would be a good time to take the oil pan off and check for metal GUNK. Also see how loose the bearings are/ movement. Sorry about this. Just don't drive it anymore because a oil pump repair is cheaper than a new engine and or disco or a new car even...

 

I looked for the life of me and could not find a oil pump for the Discovery Series 2 models on Atlantic British website. The closest thing I found were oil pump gear kits. Land Rover Parts, Accessories and Information

If you found the pump please forward the link. May come in handy one day.

Just an observation.

 

Yes, that's the one that I bought.

 

re: We were told that the knock sensor must be triggoring the oil light because all tests were fine.

Oil light is connected to one thing, a pressure switch. Knock sensor and ECU can't turn it on. Drawing attached.

This is not much help now, but I would point out the virtue of having the RAVE on a USB drive in the glove compartment. Even if the owner is not an avid DIY mechanic, the indy shop would appreciate being able to look over the manual.