What do you think is causing this?

[Armageus]

Just to confuse matters, they're referring to NGK Heat ranges in that thread, Bosch go the opposite way.

https://matchlessclueless.com/wp-content/uploads/2011/05/Temperature-range-comparison.jpg

Ah ok - that's not confusing enough

However I guess the theory could still be correct in that it may need a slightly cooler plug e.g. a Bosch "5" in order to prevent pre-ignition (assuming that's what occuring)?

Possibly only occurring in cylinders 1&2 if there is more of a hotspot at that end for whatever reason.

 

[Meaker]

Ok, it's a little tricky to get those over here.

One I saw recommended in that thread that I can get is:

50003-M40XL HKS and is their heat range 8.

Is that suitable as I am thoroughly confused now

 

[Frozennova]

Ah ok - that's not confusing enough

However I guess the theory could still be correct in that it may need a slightly cooler plug e.g. a Bosch "5" in order to prevent pre-ignition (assuming that's what occuring)?

Possibly only occurring in cylinders 1&2 if there is more of a hotspot at that end for whatever reason.

Assuming pre-ignition a colder plug may solve it, depends on the level of damage already done.

Ok, it's a little tricky to get those over here.

One I saw recommended in that thread that I can get is:

50003-M40XL HKS and is their heat range 8.

Is that suitable as I am thoroughly confused now

Based on what I can find then these https://www.opieoils.co.uk/pv-12459...plug-sparkplug-platinum-ground-electrode.aspx

 

[Meaker]

Thanks for the help

 

[Simon]

A low calcium oil will also help reduce chance of LSPI too

 

[Meaker]

A low calcium oil will also help reduce chance of LSPI too

How does the engine oil impact the ignition event? Is it a cooling thing?

 

[Frozennova]

How does the engine oil impact the ignition event? Is it a cooling thing?

Pre-ignition can be caused by the fuel pulling oil off the cylinder wall which then mix and ignite before the ignition event

 

[Meaker]

Pre-ignition can be caused by the fuel pulling oil off the cylinder wall which then mix and ignite before the ignition event

I see, interesting.

 

[Meaker]

Garage checked the coils and they tested fine, they are going to check the injectors and if they look good I'll go ahead and swap the spark plugs to the new ones.

 

[Meaker]

Ok I think it's gone now, I've got the hks plugs, shell vpower fuel and I gapped the spark plugs so they are all sitting nicely at spec.

Looks with the tune its picky but no hitching now

 

[jpaul]

so someone got spark plug 2 out, you must have changed 1 too, to drive to the dealer -

.... but without an explanation, or getting rid of the map, sounds high risk to continue using it in same manner

 

[Frozennova]

so someone got spark plug 2 out, you must have changed 1 too, to drive to the dealer -

.... but without an explanation, or getting rid of the map, sounds high risk to continue using it in same manner

There is an explaination... GDI engines are prone to Low Speed Pre-ignition, the combination of unsuitable spark plugs (Wrong heat range) and low octane fuel have been the issue from the get go. Manufactures are using various different strategies to combat it, ND MX5s are using Ion based knock detection and apply some faily heavy ignition retard to protect against it during low RPM/High load acceleration

 

[Meaker]

so someone got spark plug 2 out, you must have changed 1 too, to drive to the dealer -

.... but without an explanation, or getting rid of the map, sounds high risk to continue using it in same manner

It was just a little too hot when I tried with my crappy remover, a proper torque wrench had no issues.

Changed all spark plugs over, ran it as lightly as possible to avoid pre-ignition and drained the tank a decent amount and filled up with Shell vpower.

Double checked my gapping and cylinder 4 was about 0.5mm out so I fixed that, not sure if that tiny change will have made much of a difference.

Now it's running like it should and after a couple of days of running it in it's back to overtaking BMW 320d cars like it should

I suspect the NGK plugs straight from Hyundai probably would have been ok but I did not want to risk it.

 

[Diagro]

It was just a little too hot when I tried with my crappy remover, a proper torque wrench had no issues.

Changed all spark plugs over, ran it as lightly as possible to avoid pre-ignition and drained the tank a decent amount and filled up with Shell vpower.

Double checked my gapping and cylinder 4 was about 0.5mm out so I fixed that, not sure if that tiny change will have made much of a difference.

Now it's running like it should and after a couple of days of running it in it's back to overtaking BMW 320d cars like it should

I suspect the NGK plugs straight from Hyundai probably would have been ok but I did not want to risk it.

Why drain momentum and put in vpower?? Same bloody fuel

 

[Clarkey]

Why drain momentum and put in vpower?? Same bloody fuel