Topic

Morning,the only part that isnt working on my "F" ,is the oil temp.gauge.Ive had a good look under the car ,and the small plug which had the lead for the oil warning light ,only has that lead connected . I assume the wire for this gauge,comes off the same plug as the oil warning light .However there is only one lead coming from that plug, How can I remove the plug from the casting I dont want to try pulling it out in case there is another way Len

The plug just above the oil filter is the oil temp transducer. It should have 2 wires. One for temp gauge and one for ECU. High temp warning light comes off gauge on TF's, but early F.s had a different gauge so not sure.

To remove plug from sender push in metal clip and pull. You push clip from bottom of plug in your photo.
To remove transducer from oil filter housing unscrew anticlockwise with spanner. Oil will leak out so have a new one ready to thread back in.

Cheers, Mark

Thanks very much My "F" is an early MK 1 apparently I found this ut when looking for door switches The plug has two holes for wires,but only one wire going in Len

Looks like you have a broken wire , should have two. Cheers, Mark

From my point of view something is not correct here. There should be two (2) sensors above oil filter as per picture below.

This applies to all MG Fs and TFs.

First one ( C1666 ) should have 4 wires and is oil temp gauge sensor. Second one ( C0187 ) should have only one wire and is oil pressure switch which have earthing through fixing.

My car is an early MK1 dont know if this makes a difference lEN

Actually seems that there is a difference for early MG Fs. Of course there are 2 sensors as described above, but oil temp sensor do not have 4 wires as all later MG Fs and TFs.
It has only 1 wire Brown/Blue, as I can see on the picture in the first post.
Oil temp warning light is connected to same wire, but that light will be in use only in case of VVC engines, as it says in diagram.

Different versions seem to have different systems.

My TF135 has an Oil Temp warning light sent from sensor by oil filter, via Oil Gauge to Oil Temp warning light. If you unplug Oil Temp gauge the warning light comes on because the resistance changes. Just for interest if you fit and aftermarket digital oil temp gauge the warning light comes on much earlier as gauge has a different resistance. (Also gives you a panic attack!) I looked this all up when my original gauge died and wanted digital/accurate replacement.

My VVC 143 has an additional Oil Temp Sender mounted on the VVC gear on top of the engine. The VVC gear has three plugs , Blue and Brown for solenoids and Black for Oil Temp Switch

Both early and later Oil Temp gauges had same amount of wiring, just earlier ones had separate bulb wiring. Both gauges have signal in, power in and earth, plus power and earth for illumination. (5 wires)

So oil temp is needed by 3 things. ECU, Warning Light, and Oil Temp Gauge. It looks like there are different ways of doing this between early and late MGF / TF and also VVC engines. Interesting.

If you have access to Pscan OBD tool ( or someone with one) you can measure oil temp in real time if your ECU is receiving temp signal so you would know if that bit is working and it is just a gauge side fault.

I've gone down the rabbit hole, curiosity got the better me so delved into the EPC.

You kneed to know the VIN of your car or even engine numberto know which Oil Temp sender or transducer you have for early cars

MGF to VIN AD001017 Pt No YCB100270 150c gauge
MGF VIN AD001018 on with 170c gauge Pt No YCB100290
MGF from engine number J31/646503 and J32/646202 to VIN XD511058 Pt No YCB100350
MGF from VIN XD511059 on to MG TF Pt No100160 which has been superseded by Pt No MEK000020

Any others? LOL

Thanks for your help On the VIN PLATE ,THE NUMBERS ARE E11*93/8*0017*04
and SARRDWBGB*D507512 Abit corroded arnt we all .

OK , so your car should be late 1988/1999 with a 120ps Engine RH drive manual gearbox

That eliminates the first and last ones. If your engine number is under J31/646503 or J32/646202 then you have Pt No YCB100290 sender

If engine number is over that you have Pt No YCB100350 sender

markvrs wrote:

Different versions seem to have different systems.

"Just for interest if you fit and aftermarket digital oil temp gauge the warning light comes on much earlier as gauge has a different resistance. (Also gives you a panic attack!) I looked this all up when my original gauge died and wanted digital/accurate replacement"
Yes, I had that panic attack & it was a short while before the penny dropped. I circumvented the problem by tucking the original gauge in the void behind dash until I could resolve the problem properly. That was 18 months ago, you can get a lot more interesting stuff done in 18 months than to work out a suitable resistor to overcome that particular issue.
M