Low oil pressure light on

Hi, I am after some help please. I have a 2010 Touran 1.6tdi blue motion, the low oil pressure light came on for a few seconds then went off. I changed the oil pressure sensor switch drove it for about 20mins then came back on again for a few seconds before going off. The next day done the same, done oil and filter change and same result after about 20mins driving it comes back on for a few seconds. Just changed oil pump and pick up strainer and it has done exactly the same. Doesn't come on at idle just when warmed up. Anyone got any ideas? Could it be a wiring issue? Bearing problem?
many thanks for your help

Hi mate.
If it were me I'd do an oil pressure test next. It's easy to do as I've recently done it on my Transporter trying to sort out some noisy tappets at idle also only when hot. (still haven't got to the bottom of it yet)
I got the test kit from Machine Mart and it's pretty good quality at 45 quid but seen cheaper, similar kits on ebay.
It could be a wiring issue though as you've said but I would be keen to see what the oil pressure is like. I think if the pressure is low it could be the bearings as you've already changed the pump, Must have been a big job that ?
Sorry I can't be more helpful, Knowledge is a bit limited.

Fit a new pressure sender switch first if you don’t have access to pressure testing equipment. Only buy the switch genuine from the dealer using you REG to identify the correct one, I have lost count of the number of cars that have warning issues where people have fitted the wrong switch. I get it as 036 919 081 D and they cost £23.93.

Good point regarding the switch, I know it's been changed but it could be the wrong one of course.

I actually missed that point so yes, where did the switch come from and what is the part number?

Hi all. Done pressure test and It’s at 0.5 at idle (at 80c) when min is 0.6, and at 2000rpm it’s only 1.9 bar, the spec is between 1.5 and 5 bar (within spec but still low) been told choices of
1: Bin it off
2: strip big end shells to inspect crank and if all ok replace shells and retest with fingers crossed!!

Any ideas??
Thanks

That is not good, you have to decide whether to strip down or replace.

Does sound like rebuild time. I'm assuming it's got high mileage ?

I suppose it all depends on what the motor is worth to you. If you've already invested money into it elsewhere it might be best to get the engine re built.

It's all a question of money though isn't it ? I think the same with my Transporter, It needs a new gearbox and along with that will come a Flywheel and clutch, also needs the Crank seal doing while it's out. Engine is giving me a nightmare with new tappets I've had fitted and then there's the bodywork which is needing attention. Do I get rid and buy something else which could give more unknown hassle or spend on the one I've got ?

If the rest of the car is good and you rather like it, If it were me I'd probably spend some money on getting the engine sorted rather than buying another load of trouble especially If you can do the job yourself. That's just my thinking anyway but good luck with it if you decide to strip and re build.

Can I ask where you got the oil pressure figures from ? I'm wanting to know what the pressure should be on my Transporter at idle but all I've got is a figure what it should be at 2000 RPM (which it was well within).

Cheers

I had a 2L CR TDI 14 chassis Octavia in today with a noisy top end. No warning lights but quite clearly tappet rattle. We did an oil pressure check which showed 4 Bar at idle for a moment and then dropped to 1 Bar no matter how it was revved, I think it is the oil pressure regulator valve but as this costs about £90 and means removing the A/C compressor, the owner wet himself and ran for the hills.

Would you say that 1bar at idle is rather low ? I realise every motor is going to be different. I'm only asking as I'm trying to find out what my Transporter (2.5 TDI) should have at idle but to no Avail yet. I have a maximum pressure of 4 bar, seems to peak at 3000 rpm and around 1 bar at idle. 3.4 bar at 2000 rpm.

Off topic on this thread sorry but still trying to find the reason why new tappets are rattling at idle. Personally, I think the tappets are to blame as they are non genuine (INA)