Miata has slightly low idle below 1000 rpm

[BlitzWing]

Not a major issue but this is something that has bugged me since I got the car. It idles on the line below the 1000 mark. I've been told its ideal to have it between that line and the 1000 mark line.

I've done the idle reset and it actually idles at the correct point until I turn off the engine and remove the paperclip and try it again.

could it be an ECU issue? the car drives fine in every respect. I've swapped HT leads so maybe the spark plugs are on their last legs or coated in crap? (I don't have a socket to remove them I lent it to a friend who "lost" it)

[Left0verCurry]

Idle should be at 850-900rpm. Looks like its normal on your car if it idle one line below 1k.

[BlitzWing]

maybe it was because my old 97 had a higher idle and this car came with a lighter flywheel but it just seems a bit off

[WASABI]

I'm curious as to what exactly you are feeling? I have mine set to 800 RPM (1.6L) and she feels great, very peppy. Is your 94 a 1.8 in the UK? I ask because I thought you could still get a 1.6 after 93... that being said, would there be a different feel when you reved a 1.6 compared to a 1.8?

[BlitzWing]

my current car is a 94 RS-Ltd so its a JDM import with a 1.8 and the lighter flywheel otherwise normal to any early 1.8. My 97 was a UK spec 1.8 with the later model 1.8 revised engine. Both almost stock bar headers and exhaust. Maybe I'm just feeling the effects of cold wet weather after a long summer (well long for the UK)

a bit off topic we could still get the 1.6 up to I think 02 maybe into the Mk2.5's but I've never driven a 1.6.

[WASABI]

Hmmmm, as a cheap maintenance items, I would throw in a correct set of plugs, NGK blue wires (they last about 30,000), oil change, and fuel filter. Then you'll start a baseline that you start from. Good luck.

-Jim

[Madaboutmx5s]

Hmmmm, as a cheap maintenance items, I would throw in a correct set of plugs, NGK blue wires (they last about 30,000), oil change, and fuel filter. Then you'll start a baseline that you start from. Good luck.

-Jim

Good advice as idle problems, etc can be sorted though the above. Your car (my old car) sounds fine for idle. If it was using too much fuel I'd say O2 sensor, coolant temp sensor, etc but unless you getting idle droop I'd leave it alone.

[BlitzWing]

guess I should update this the problem just kinda went away over a few weeks don't know what set it off.

[kung fu jesus]

Did it coincide with a cold snap in the weather?

[speedypenguin]

^I was going to suggest this too. My car has idle problems once in awhile when it's very cold.

[BlitzWing]

could have been. It's been colder lately but my commute is much shorter these days and I've played with the idle some more. I've put it down to a few small factors adding up.