Changing MX5 NC2 Fuel Filter

Technical Area Engine, Transmission, Exhaust etc
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  1. My model of MX-5 is: NC2
  2. I’m based near: Manchester
  3. I’m looking for technical help or recommendations on:

Hey guys,

Looking to change the fuel filter on my MX5 as Im getting horrible MPG, something close to 21-23, while I hear others get like 28-30 :frowning:

I can’t find too many videos on how to get it done, I’ve found one for an NB where you remove the fuel pump fuse - then the fuel cap & start the car to drain the fuel from the system,

then they proceeded to remove & install the new fuel filter - would this be the same case on the NC or is there anything else that I should know of before I start breaking my car,

Any other recommendations for fixing my MPG would be great - I do want to see if the car is running rich but first the fuel filter,

Thanks all

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I think you need to look in other areas first.
How many miles has the car done?
Plugs need changing?
Thermostat broke?
Brakes binding?

Never really heard of anyone needing a fuel filter change, always a first of course.

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cars done around 83k miles,

I changed the plugs to brand new ones not long ago,

Not sure about thermostat & I dont think the brakes are binding - How can I check to be sure though?

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Gauge on the dash should show slightly below the centre mark when at normal operating temps. Slow to reach that mark (within 2-3 miles normally, less in summer) it’s not doing its job.
Brakes, well if binding one or more discs could be getting hot. Me, I give it the touch test, the alloy wheel not the brake discs. If hotter than the others it’s binding. Bear in mind the fronts will get to a higher temp with use than the rears.
TBH if the car won’t go forwards or backwards easily on a flat road/driveway when pushed from stationary maybe a brakes binding. It’s got to be binding pretty badly to reduce the fuel consumption to what you say and I think you would most likely smell realise it too. Don’t touch hot brake discs, you can’t get a temp meter to check this sort of stuff out.
Other than the above (easy to check) its either fuel related, maybe a sensor somewhere in the system faulty.

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I think if there was that much friction from binding brakes, you would smell them.
I certainly did when mine were binding.
Use MickAP’s advise and go through it methodically👍

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What condition is the air filter in?
Is the car auto or manual gearbox?
Have you checked for fault codes?

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Symptoms of a blocked filter would be fuel starvation but you don’t mention if the car revs freely or not or shows any hesitation to rev freely.

Assuming the brakes are not binding and the air filter is clean then I would have an emissions test to check for rich running. I would also check for any engine fault codes and the exhaust system for signs of leakage.

You do say the spark plugs have been changed, are the correct type fitted? An MX5 parts supplier once sold me 1.8 plugs for my 2.0 NC.

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