engine idea when put into gear

[metal matt]

Gents
I'm looking for a bit of info from anyone with an MX5 build. When I put my car into gear the revs go up from normal ideal. I've done some reading and looking on the MX5 forums and they all point to the clutch switch. I currently don't have one but My question is what have you guys done about yours, fitted the switch or bypassed it.

https://www.flickr.com/photos/124541083@N02/
https://haynes.co.uk/forums/showthread.php?t=13262

[Numplumb]

Hi my mx5 16 does the same when I depress the clutch pedal also when i press
The brake pedal I have the clutch switch fitted
Regards Mick.

[RichardH]

interesting to know the outcome of this, im starting on my loom shortly and was intending to bypass the clutch switch, seems it may be required?

[RichardH]

reading the saturn plans it says the switch make the engine take more fuel when the clutch is pressed therefore if bypassed it will overfuel all the time.

[metal matt]

I haven't had a chance to have a look yet but reading through things there is 2 switches on the clutch. The first is for (push the clutch in to start). I found out about this one when trying to start my engine for the first time.
The second switch is the clutch switch, which I believe from reading and looking on my wiring diagram go's to the cruse control (push clutch in turns off) if I'm right.

So my symptoms are when I put it into gear the revs go up. Reading about this it is not picking up on the Switch so the ESU is compensating for it thinking it is going to stall I think.

I did also read something about it over fuelling when they don't work.

I will try to bypass it to start with to see iv the revs change then if they don't I will have to try and squeeze down into the foot well and try and fit this switch.



https://www.flickr.com/photos/124541083@N02/
https://haynes.co.uk/forums/showthread.php?t=13262

[flyerncle]

Not had much to do with MX 5 but most engines that have sensors on to lift the revs when loaded ie power steering /ac etc either put air into the manifold or move the throttle body.

[metal matt]

Found this and a good bit of reading on the switches

http://forum.miata.net/vb/showthread...=282088&page=6



https://www.flickr.com/photos/124541083@N02/
https://haynes.co.uk/forums/showthread.php?t=13262

[Numplumb]

Originally Posted by flyerncle

Not had much to do with MX 5 but most engines that have sensors on to lift the revs when loaded ie power steering /ac etc either put air into the manifold or move the throttle body.

On mine the revs go up slightly when I put on the headlights

[garyt]

hi , now its running again went and tried mine, in neutral standing still it idles fine, clutch in still idles fine, put it in gear and without touching the throttle the revs rise.... not alarmingly enough to notice and as soon as I go to move its fine.
Its almost like an anti stall if there is such a thing. Its certainly not something for me to worry about... yet

[garyt]

mmmmmm
thinking about this . if sticking the clutch in makes no difference UNTILL its put in gear then it cant be a clutch switch as this would only see clutch in or clutch out . so there must be a sensor in the box as this is the only way any sort of signal can be sent to the ecu. as with the clutch in and no pressure ont throttle there is no other signal sent.
yes switching something on would cause a rev increase because you are putting a load electrical / mechanical on the engine so for example lights on = more currant drawn so revs rise to supply more alternator speed etc,

methinks some searching is in order mmmmmm