zrs6v4

I have a stock 95 SC300 and I just drove it yesterday and noticed it was misfiring a little so I popped the hood and heard a strange noise. I removed the timing cover and noticed the first plug wire had come off. I then shined a flash light in the plug hole to see the first section filled up with oil and coolant. So today I removed the intake and valve covers and noticed a few things

-The valve covers were only on hand tight.
- all the spark plug sections were full of oil and coolant

So what could be the cause of this happening, I noticed that there were 3 large allen head screws in between each plug and was wondering if there was a gasket in them that could be bad.

any advice is awesome, I dont think this is a big deal because I noticed it quickly, but havent came across this in my lifetime, hah.

- I did plan on replacing the plugs and VC gaskets. So let me know if youd replace anything else while Im in there.

5sp_jzz30

iTrader: (2)

usually misfiring can happed when the coolant hose on the back of the head breaks and pours coolant on plugs 5 & 6.

this has happened to me and to a couple of other members.

the hose frays after years and also due to had trans and motor mounts.

check the hose and replace your VC gaskets.

KC95SC400

iTrader: (3)

You might need to re-seal the spark plug tubes as well, if they are removable. Not sure on your motor.

KC

5sp_jzz30

iTrader: (2)

theres no spark plug tubes. the 2jz has 2 separate valve covers with the plug sitting in between the cams. there are no seals.

KC95SC400

iTrader: (3)

I didn't really think so but wasn't sure.

I work at a Toyota dealership and we don't see SC300s, or even Supras very often so.......... They do tend to leak on 4cyl Camry's though.

KC

zrs6v4

thanks, I was actually thinking my heater core hose was looking rough. It must have leaked so bad it overflowed into the other cylinders. I will get the VC gasket set and heater hose.

is there anything else that may be leaking coolant badly into the spark plug grooves?

megamax

iTrader: (9)

bumping this thread, I'm also having this problem. I have temp bypassed my heater core and now I find coolant on my spark plug tips, fresh off a complete rebuild, I have no coolant in the oil or overheating, any ideas?

RXRodger

iTrader: (2)

What about the throttle body coolant circulation hose, what condition is it in? Any evidence of it leaking?