I don't suppose anyone knows why my MPG gauge never seems to work? I've owned the car over a year now and have only ever seen the dial work once. (The one time I did see the needle, it was just a small yellow needle like the petrol and temp gauge) Is it possible my fuel economy is that bad that the dial doesn't reach 25? Also just an additional question, could anyone tell me what dash I have? I've looked all over the internet and can't seem to find a mk2 with the same clocks as me. Thanks
Hello, joe, As I understand these instrument clusters, the mpg indicator has a vacuum pipe attached at the rear of the module. I take it that this comes from the inlet manifold.
Thanks, I'll take a look. I've seen from another thread that the gauge can work off the reverse light switch. As it stands, my reverse lights don't work so could this also be a factor?
No sorry not sure best to check connections for corrosion and if the dial still works or if there is a vacuum leak.
yes for the needle to work you need a working 5th gear switch on the gearbox, these are only fitted on early box with the big multi pin plug. if you only have a 2 pin plug on the box this is why the mpg gauge wont work right. the shift light is controlled by the vacuum switch hanging around in the engine bay somewhere, has red/white and brown wires on the 2 pin plug. this is common with the wiring to the reverse switch, the 5th gear switch and vacuum switch share a common earth thru the plug which connects the reverse/mpg wiring loom to the headlight and engine looms. its an unsealed spade plug so make sure all is clean and tight
Any chance anyone has a diagram of the shift light wiring and mpg gauge? Where can I find the vacuum switch and reverse light switch? The needle has momentarily worked so I must have the big multi pin plug if it’s worked in the past. I’d just like to get an accurate reading of my mpg because the mfa never goes above 20mpg which I ready could be a faulty reading due to a vacuum line. If anyone knows the full layout of the shift light and mpg vacuum lines and switches, that’d be great
I’ve now confirmed from the VIN it’s a type 19 but with a different engine in place. I’m yet to confirm what engine it has but I do know it’s 16v with KJet. Hope that helps
I take it it's had a 16v conversion done at some time as they are 8v clocks aren't they and didn't a 16v come out in 86
Yeah 16v engine. Shouldve clarified type 19 8v originally but now 16v with same clocks. There’s a lot of unplugged wiring in the engine bay and I’m struggling to match it up to stuff
check my signature link for 'g2krecuce1.pdf' that should hopefully help you on the 16v wiring side. do you know if its had full 16v loom put in or had 8v loom adapted? the 16v loom has extra wiring in it for the ISV and over-run cut-off valve, with the isv control module sat behind the console. often not fitted, instead idle speed increased and/or 8v AAV unit swapped in place of the isv to get engine running without heres a MK1 MPG gauge & upshift diagram. Its all the same as MK2 except for the clock pins as they use different cluster sets, can be reasonably sure that'll have been left alone when loom was done: F62 - vacuum switch F68 - 5th gear switch G51 - mpg needle N60 - solenoid valve for mpg needle K48 - gearshift light
Thanks for the help. I’ll take a look. As far as I know it hasn’t had a full loom switch, you’ve told me in the past to unplug the isv relay and it made no difference to the performance of the engine so I’m guessing it’s still 8v wiring
