MX5Ireland

Our Eunos is misbehaving. When started from cold it will idle fine and if left to warm up for 2 mins and the driven it is fine.

However, if started from cold (must be properly cold, left for 6 or eight hours), if you drive it it is dead, and will cut out if left to idle in the first few mins of driving.

Once warmed up it is fine, runs perfectlyu smoothly.

Any ideas what could be causing this? I have checked the HT leads, all are seated correctly, no obvious loose connections.

check the intake tubing for a leak,
then your O2 sensor,
Idle Control Valve would be next I reckon..

I've a 90, and EXACT same issue! Checked everything on it still can't find the issue, I've just settled to letting her tick over for 3-5 min, then driving off!

Hoping to not settle for good enough, there has to be some solvable problem here and I wanna know what it is. Goinf to take out the throttle body and take a look this evening. Will also check for leaks - not likely, as it runs very well under normal conditions.

There is a sensor at the back of the engine hear the bulk head... I think its the water temp sensor and there fore could be causing your problem

somclan wrote:There is a sensor at the back of the engine hear the bulk head... I think its the water temp sensor and there fore could be causing your problem

Good point, I'm thinking that it has to be temp/dampness related, so that rules out the crank sensor.

It would seem like the leads, plugs, coils or temp sensor has to be it really.

I guess I'll start cheap with the plugs and leads, then the temp sensor.

Anyone have a coilpack they're not using for a test? Long shot I know, but worth a go.

EDIT: Another question actually - I know there is a T sensor on the front of the engine, for the fan, and I know there is 1 or 2 more in the rear of the engine - how many T-sensors in all? And which one sends its signal to the ECU?

the one on the back of the head is the one for the ECU cold start setting AFAIR.

So there definitely are only 2 T-sensors on the engine? One front for the fan and one back for the ECU/guage - can anyone confirm that?

Looking at this there may be 3?
http://www.mx5parts.co.uk/advanced_sear ... 44&x=0&y=0

Theres three, heres the two at the back of the engine, the one in the thermostat housing (one wire) is just for the fan.

That's the biz guys - thanks - I was suspicious from looking at the MX5parts site - looks like I'll replace the sensor and see how it goes - hopefully will be able to reach it if I can get the coilpack out of the way.

£27 is taking the mickey though - might try the local motor factors and see if I can find one - may be a unoversal fit like Lambda sensors.

cool. Let us know if you find an alternative.

BTW, check this out :
http://www.boundville.co.uk/temperature ... -375-p.asp

RIght, the temperature sensor is fine - disconnected it and no effect - and there are no codes in the ECU.

Running out of ideas now.

Doesn't that mean it might not be working tho?

<edit> Ignore me.. no it doesn't </edit>

BTW, when was the last time you changed your plugs and ignition wires? Worth doing anyway if they're a few years old.