Spark plug damage

[The Hornet]

My car wasnt running smooth as i described in my previous post. MartinF suggested I check the hoses etc which I have just done. There all on and tightly secured.

That's the good news.

I then proceeded to check the spark plugs...

One of them is damaged..

The ceramic which surrounds the electrode on the end of one of the plugs has a 5mm X 7mm chunk missing. Now the bit I mean is the electrode which is inside the cylinder and fires the spark to the prong. Well its the ceramic which surrounds it which is chipped.

My guess would be that this has happened due to the heat as the car was running smoothly and then gradually became worse until it felt like it was not running on all cyclinders.

I have some Denso IK24's coming in next few days.

I'm just about to go take plug out and see if the chip blows out but if it doesn't does anyone know if there is a path way back to the oil, as if it has been crushed and mixed with the oil I'll need to do an oil change. Also do you think it may have caused any internal damage i.e valves or seals etc?? ?Urgent help would be appreciated.

I would say the car has covered about 150 miles whilst not running smoothly http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/sad.gif

Hornet.

[Martin F]

Well i never.......

Worst case its scored the cylinder walls and you'll have poor compression and need to strip the block down.

Best case it would of left via the exhaust port causing no damage.

[Suprz_RZ]

Left by way of the exhaust port, and not rammed its way through your turbine blades eh?

[Martin F]

Depends if its Jap or UK spec. Steel baldes on the UK spec would be a little more resistant, but hey i'm sure a lump of ceramic coming at them when they're doing 100,000rpm would cause a few problems unless the luck of the gods was with Mr Hornet and it travelled inbetween the blades.

[GavinL]

Any update on this?

[The Hornet]

Well i've fitted the Denso IK24 plugs and its running a little smoother but is still not right. My guess is that the pieces of ceramic must have damaged something http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/sad.gif I took it to Toyota main dealer and they said they couldn't find a problem and that they run like that (what a waste of space they are! they even said they can hear the turbo's spinning up and the dump valves working fine, thing is I haven't even fitted the BOV yet, what they heard was the Apexi intake noise, doesn't enspire confidence in Toyota main dealer).

I've got it booked in for rolling road next saturday.

After driving it a little more i can describe the fault a little better - It idles ok but now and then judders as if mis-firing, when accelerating with just a little bit of gas it judders quite badly. Also when keeping constant speed say 60mph it judders. If I push gas pedal about half way or a bit more it accelerates but judders and now and then the full power kicks in and out ? I can hear boh turbo's come in so don't think its them.

I'm still baffled really to what it could be. The car is J-spec, I have all my mods sat in garage waited to be fitted but want it running properly first http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/sad.gif The only mods fitted are Apexi intake and Blitz NUR Spec R Cat back. And the IK24's now. I have put my OPtima Yellow top battery in and re-wired the positive and added 2 extra chassis ground points just to make sure the power feeds are in top shape. I have already checked all the hoses as MartinF suggested but they all seem fine.

Any other ideas?

Thanks in advance.

Hornet.

[The Hornet]

Oh and even if I floor the car it still judders with full power juddering in and out now and then. Also I checked to see if I could see and smoke from the exhaust but it seems clean as a whistle. Although when I look in the end of my exhaust its very black, is that normal, as i would say its running a little rich ?

Hornet.

[Martin F]

Quote[/b] (The Hornet @ Aug. 09 2004,08:40)]I've got it booked in for rolling road next saturday.
I would strongly advise that you do not do this. Sorry if it seems a bit doom mongering but seeing some of these cars on the Dyno you can't believe the stresses that they can go through. If you have a minor issue i can see it all ending in a big bill.

The best way(reasonably priced) to eliminate problems by loosing that bit of ceramic from your spark plug is to have a compression and leak down test done. This will eliminate problems withing the cylinders.

Then for the turbo's it's really as simple as checking the boost being produced. Whilst it won't be 100% conclusive, chances are if your turbos can produce their normal levels of boost not too much can be amiss.

If all that checks out and you still have a problem then i'd suggest pulling the ECU faultcodes to see if they show anything up.

[GavinL]

Quote[/b] (Martin F @ Aug. 09 2004,09:10)]Quote[/b] (The Hornet @ Aug. 09 2004,08:40)]I've got it booked in for rolling road next saturday.
I would strongly advise that you do not do this. Sorry if it seems a bit doom mongering but seeing some of these cars on the Dyno you can't believe the stresses that they can go through. If you have a minor issue i can see it all ending in a big bill.

The best way(reasonably priced) to eliminate problems by loosing that bit of ceramic from your spark plug is to have a compression and leak down test done. This will ?eliminate problems withing the cylinders.

Then for the turbo's it's really as simple as checking the boost being produced. Whilst it won't be 100% conclusive, chances are if your turbos can produce their normal levels of boost not too much can be amiss.

If all that checks out and you still have a problem then i'd suggest pulling the ECU faultcodes to see if they show anything up.
You might want to visit Chris Wilson to get this investigated.

He has the facility to look into the engine bores with a scope and I'm sure he can to a leak down test as well

[The Hornet]

Have contacted Chris Wilson and cancelled the rolling road test.

Thanks guys, much appreciated.

Hornet.

[The Hornet]

Eventually got it sorted, two of the coil packs were faulty. Got them replaced under warranty and now she runs very nice again http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/biggrin.gif going on holiday for two weeks now so will fit the rest of my mod's when I get back. Can't wait http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/cool.gif

[Martin F]

Thats good news and even better that they were covered under warranty as the coil packs are not the cheapest part in the world.

Have a good one.

[The Hornet]

Yeah I gathered they are quite pricey like most parts for the Supra, thats why I bought it from a dealer and had them throw in a 2 year warranty inc. turbo's http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/cool.gif

Thought it to be a better idea than bartering on the price.