I have had my 5 a few weeks now and after my little diesel corsa before i thought it was gona use a bit more fuel but like 100 miles from £20 is bad isnt it, ib bin thinking its ovefueling for a a while now until yesterday when it was a cert when my mate revved it lighly for me and i felt liquid fuel on my hand from the exhaust.
Anyone got any tips of what/ where to look first ( im pretty handy under the bonnet so will do it my self but im still getting to grips with this car yeat…first jap n’all )
The liquid from the exhaust is probably condensate (water) rather than petrol. Check the ECU for fault codes; a faulty water temperature sensor and/or O2 sensor could cause it to run rich. Depending on the exact model of MX-5 that you have, the O2 sensor could cost as little as £12.50 to replace.
100 miles from £20, assuming £1.17 per litre = 17.09 litres/4.546 = 3.75 galls. 100/3.75 = 26.66 mpg. About what I’d expect as the bottom end of fuel consumption. If your fuel was more expensive your mpg is better!
What sort of driving are you doing? Daily commute in stop start traffic or blasting round country lanes. That’d be about right.
Check your tyre pressures and the weight of your right foot first. Cheap/easy improvements to be had there.
I get 27-32 commuting and up to 47 on the French Peage on my trip back from CLM - but we were travelling at a steady 65, nursing two sick Triumphs back home with the convoy.
Blasting round country lanes I am getting 30 to 32mpg from a 90 1.6 so it may well be down to the nature of driving you do. By comparison I get @ 42 to 45mpg from my Octavia VRS going a bit faster, which is pretty impressive given it weighs a lot more
IMHO most MX5’s run slightly rich, I’ve had two Mk1’s (both 1.6) and my current Mk2.5 (1.8) have always had slightly blackened plugs.
That’s not to say I think there’s a fault, from what I remember reading somewhere it’s best that way. I ended up buying one of these in the end http://www.scangauge.net/ just so I could get a good measure of what’s going on - great bit of kit by the way.
Work is only 6 miles away for me, the first 3 miles of which are up hill so that doesn’t help (nor does my lead foot). Out of a tank I usually see 230-250 miles which is rubbish to be fair but I do a lot of short journeys so it’s to be expect.
IIRC, they run especially rich over 4k? Something to do with detonation/pinking prevention? Best I’ve squeezed out of our Mk2’5 is about 33mpg. The 1840cc Auto? Don’t go there!
