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mk3s defo dont have low fuel warning lights. Trust me. Its just coincidence. Look at t'symbol above the light in the clocks - what is it?

Yeah the oil light should blink when the engine isnt turning over, The temp light should flash a couple of times before going out (this is the one you think is a fuel one I bet)

It just so happens that ive still got my old CL clocks complete with all 4 of the red LED's: left to right, 1) is battery 2) is oil 3) is coolant temp 4) is braking system and handbrake.


But the oil light going out aint right. So yes I would assume oil pressure sensor failure. I would guess its the high pressure sensor as the buzzer only comes on when you rev it doesnt it? (assuming you have 2 sensors that is)

Its temp then, (the second light from the end). My CL clocks never had that light. Yes, problem occurs upon revving. Varies though, as to what rpm it occurs at. some days as low as 2k rpm and the buzzer goes off.

Karl.

Yeah, 2K rpm is where it switches reading from the low pressure sensor to the high pressure one.

Btw (usless bit of info) the one at the right hand end that doesnt do owt is for diesels, its a glow plug indicator although Ive never seen a set of clocks with one because there wasnt a mk3 diesel polo in the uk

Gareth_GT_Hatch wrote:Yeah, 2K rpm is where it switches reading from the low pressure sensor to the high pressure one.

So theres a chance I've 2 sensors? If thats the case that isolates high pressure one as faulty.

Karl.

I would assume so. I dont know which sensor is the high pressure and which is the low pressure one though. It might be possible to unplug each of them in turn with the engine off to see if it makes any difference (no difference would expose the faulty one). Do you know where the oil pressure sensors are? Theyre pretty easy to find.

Your help in locating them greatly appreciated...

Thanks.

Karl.

If the car ever had a petrol light, then i should certainly know What you described as the "petrol light" is almost certainly the coolant temp light...

What revs do you generally get the buzzer at? My manual states that if there's a problem with oil pressure, the light flashes, and the buzzer sounds "at engine speeds over 2000rpm"...

Oil level *at* max isnt a problem, though over max is. The general theory is - at or near minimum, you SHOULD top it up, from about one-quarter to one-half way up you CAN top it up, and any further than one half or 2/3rd you're best to leave it. Carrying out the simple operation of waiting for it to hit MIN, opening a 1-litre top up and emptying the contents into the engine should take it neatly to the MAX mark. (i should expect you have a little leeway either side... no-ones perfect.... otherwise they wouldnt have installed a rev limiter either )

Right, theyre next to each other on the back of the cylinder head on the right hand side on the engine bay (as you look at it) One has a blue wire coming from it, the other has a yellow wire. You might need to take off the airbox to see them better

i had this problem when i changed the clocks in my old polo its because your car only has a senor for checking low oil pressure whereas the gt has one for checking the low and high pressures to overcome this problem what i did i know its a bodge but i soldiered a wire connecting on the back of the clocks from the high to the low to fin ot hich ones need to be soldiered look at the wiring diagrams in the back of the haynes manual ( haynes book of bull s**t!) lol

I don't suppose you have any diagrams? Or if I scanned the manual in for the clocks, then would you be able to show me which connections need doing? Even better would be a pic of the connector plugs, and where you soldered them.

Thanks.

Karl.

Is it just the later cl's that have only one sensor?
My 91 j plate has the clocks in and its fine.

I will try the sensor. Best thing I can do is pop the bonnet and identify whether I have one or 2 sensors. If its 2, the high pressure is causing problems. If it is one, there is a bit of electrical bodgery to be done.

Thanks again everyone.

Karl.

Right, tried the car again after it had reached running temperature. Starts flashing and beeping at me at round about 2100rpm. There is now no variation. I removed the airbox prior to running the car and had a look for the two sensors. I assume these are the sensors, just which one is which?





I am thinking the smaller of the two is the low prssure, so the bigger one is high pressure? Am I right? Both lead into the car via the bulkhead. Which one do I replace, and which part? the plug going to the instruments, or the socket from the engine? (Thats all assuming I have found the right sensors?)

Thanks.

Karl.

dude you're miles off:



It looks to me like youve only got one oil pressure sensor. The one ive arrowed is the only one i can see (the other one should be next to it) Could have done with a bigger pic but never mind. Note that the thing above the yellow box is nothing to do with the oil pressure sensor, The oil pressure sensor is underneath this in a way and has 1 wire going to it.

You are indeed right. Now then, that means I either need to do some dodgy soldering, or if someone can tell me whether Genesis clocks have provision for one sensor, that would be much appreciated. And thanks for steering me in the right direction Gareth.

Thanks.

Karl.