Revs changing and loose gear knob
Discussion
Recently the car has changed the way it revs when starting. Sometimes it starts normally and goes to 1500rpm, before slowly dropping as the car warms up. However recently it has started "blipping" up to 1900rpm before dropping quickly down to 1500rpm and then behaving normally. It's like I have my foot on the accelerator when it starts for a second or two. This happens when warm and cold. Any ideas on what it could be?
Also the handle on the gear knob is loose, but it's not the actual stick itself. It just turns around without moving the stick. A bit annoying when driving and it ends up facing the wrong way! Is there an easy way to fix this? From what I understand you'd normally unscrew the stick by using the gear knob. Since this won't move the stick then that's not an option, and the gaitor prevents access to the stick itself. Do I just have to cut the gaitor and unscrew the stick and replace the gear knob?
Also another point while I'm posting. The car seems to like to "wander" sometimes, and is quite crashy on bumps. Is this the bushes that are gone/ going?
As you can tell I'm not very technical, so any help is appreciated.
Also the handle on the gear knob is loose, but it's not the actual stick itself. It just turns around without moving the stick. A bit annoying when driving and it ends up facing the wrong way! Is there an easy way to fix this? From what I understand you'd normally unscrew the stick by using the gear knob. Since this won't move the stick then that's not an option, and the gaitor prevents access to the stick itself. Do I just have to cut the gaitor and unscrew the stick and replace the gear knob?
Also another point while I'm posting. The car seems to like to "wander" sometimes, and is quite crashy on bumps. Is this the bushes that are gone/ going?
As you can tell I'm not very technical, so any help is appreciated.
For the wandering/crashy ride, check your tyre pressures! Mine were at 32PSI when I bought the car and it felt precisely how you describe it. Backed them off to 28PSI and it's lovely. While you're at it check for uneven tyre wear, as if the tyres have been overinflated for a while they might be wearing out fast.
I know the knob is attached to the stick, the problem is it's now just turning without the stick turning (basically it seems like the thread has been stripped, if that is possible).
ETA: Tyre pressure is ok. Tyres are also new as the previous ones when I got the car were from 2005! Toyo T-1 Rs all round.
What manuals are there for the NB, as far as I'm aware there is only the ones for the NA 1.6 and 1.8l cars. I've just searched the internet in the past when I've needed to find out stuff (e.g. replacing the power aerial).
ETA: Tyre pressure is ok. Tyres are also new as the previous ones when I got the car were from 2005! Toyo T-1 Rs all round.
What manuals are there for the NB, as far as I'm aware there is only the ones for the NA 1.6 and 1.8l cars. I've just searched the internet in the past when I've needed to find out stuff (e.g. replacing the power aerial).
Edited by Mx5guy on Monday 18th July 14:59
Is your knob (*snigger*) one-piece or is there a metal collar at the bottom of it where the stick goes in? If so it's an aftermarket replacement so the collar might well unscrew to reveal grub-screws that should hold the knob in place.
When you say the tyre pressures are correct are you saying that because you've checked them or because you are trusting the tyre fitter to put the correct pressure in? In my experience they never do. However much I insist that I need 27psi and however much they say they will do that they always come back with at least 32psi, often much higher.
When you say the tyre pressures are correct are you saying that because you've checked them or because you are trusting the tyre fitter to put the correct pressure in? In my experience they never do. However much I insist that I need 27psi and however much they say they will do that they always come back with at least 32psi, often much higher.
beeblebrox said:
MX-5 Lazza said:
However much I insist that I need 27psi and however much they say they will do that they always come back with at least 32psi, often much higher.
Maybe the fitter puts 27PSI in before fitting the wheel back onto the car?MX-5 Lazza said:
Is your knob (*snigger*) one-piece or is there a metal collar at the bottom of it where the stick goes in? If so it's an aftermarket replacement so the collar might well unscrew to reveal grub-screws that should hold the knob in place.
When you say the tyre pressures are correct are you saying that because you've checked them or because you are trusting the tyre fitter to put the correct pressure in? In my experience they never do. However much I insist that I need 27psi and however much they say they will do that they always come back with at least 32psi, often much higher.
I have checked them. The last time was 2 weeks ago, but I checked last night just in case, and they were correct. I didn't trust the tyre fitter to "get it right" when they were done and so checked them straight away, but they were actually very close.When you say the tyre pressures are correct are you saying that because you've checked them or because you are trusting the tyre fitter to put the correct pressure in? In my experience they never do. However much I insist that I need 27psi and however much they say they will do that they always come back with at least 32psi, often much higher.
My knob is original! It's the 10th Anniversary one. I tried playing with it a bit more and it just keeps turning so the plastic thread must be broken. I guess it's just trying to see how to get it off, and get a new one (hm, now should I get an original one or go for something new...
). I do like the original, and don't want anything metal due to driving the car in -20 during winter (getting my hand frozen to it does not sound like a good idea!).I've booked the car in to get checked for the wandering about/ bumpy ride. It's just spoiling the great driving. Unfortunately they don't have time before the trip to Trollstigen and Geiranger this weekend,

An alignment check will probably clear up the wandering. As for the car's cocking about with revs then you can try resetting the base idle.
It's all on miata.net/garage somewhere but it basically involves cleaning the air flow meter (The bit that's attached to the top of the airbox), cleaning the bit below the throttle body (can't remember it's name off the top of my head now) then shorting some pins (GND + 10 iirc) in the diag plug and turning the idle adjuster screw on the TB until you get it at about 800.
Takes about 1/2 hour and mine's perfect now. It used to kill itself at lights and wake up the neighbours on cold mornings.
It's all on miata.net/garage somewhere but it basically involves cleaning the air flow meter (The bit that's attached to the top of the airbox), cleaning the bit below the throttle body (can't remember it's name off the top of my head now) then shorting some pins (GND + 10 iirc) in the diag plug and turning the idle adjuster screw on the TB until you get it at about 800.
Takes about 1/2 hour and mine's perfect now. It used to kill itself at lights and wake up the neighbours on cold mornings.

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