coil pack

[toro126]

hi guys need help,

my wife was driving today and the corolla started to mis and backfire a little bit, so i jumped in to the drivers seat got on the m5 then i gave it a thrash, 10 mins laters heard a wired noise and car had no power and sounded like exaust leak. i realised i was running on 3 cylinders got home and found dat the seconed coil pack cracked out of place pushing the engine cover out. i removed the coil pack which was melted and broken removed the park plug and it was completly burnt out....why would this happen any help thanx

[DJKOR]

When you say 'burnt out' are you referring to the top (connection side) of the spark plug or the bottom (cylinder side). It you were referring to the former, the damage you would see there would most likely have been caused by the ignition coil arcing to whatever metal was nearby in the the spark plug cavity. As for it coming off and causing that in the first place, it's hard to determine exactly how that came to be. Usually it is held in fairly tight, and doesn't just come loose like that. Has the engine been serviced or worked on recently?

[CHA54]

is it indonesian or japanese made?

If the coil split down the side at the seam it can arc out to the head, suprising the ECU kept firing and didn't switch into limp home mode after the IGf signals from that coil stopped.

I've heard of some of the indonesian coils failing.

[toro126]

is it indonesian or japanese made?

If the coil split down the side at the seam it can arc out to the head, suprising the ECU kept firing and didn't switch into limp home mode after the IGf signals from that coil stopped.

I've heard of some of the indonesian coils failing.

no, its jap. THE BURNT OUT BIT ON THE PLUG IS WHERE IT SPARKS FROM AND THE THREAD IS GONE. i tried to put new spark plug but the thread is gone on the head.the tip of the coil melted and broke.so naw i gotta remove the head.its got 158,ooo km on it.its a 2004 corolla.i juz dont know wat caused this.

[DJKOR]

Damn. When I first read your post and you mentioned how it pushed the cover up, I thought this was the kind of scenario you were talking about. I didn't really think that it actually did happen. That's pretty serious. When were the spark plugs last changed? And by whom? Over tightening them could have led to that.

[CHA54]

you should be able to get the plug thread helicoiled to repair it without needing to remove the head.

[toro126]

you should be able to get the plug thread helicoiled to repair it without needing to remove the head.

the plugs were changes bout 4-5months ago.by a friend.what worshops or mechanics do helicoil? cylinder head recons?

[toro126]

the plug thread has thread on it but near the tip the thread is a bit wavy.the new plug feels like it want to wind but then juz lets go and keeps spining it doesnt really wanna grap.

[CHA54]

look up mobile thread repair people in yellowpages etc, eg http://www.aussieweb.com.au/details.aspx?id=1693483

[Spirited]

thats a bugger to hear mate. Hope you can get it fixed well.

I think possibly, with the plug being burnt up, is it possible that the thread was stripped when the plug was installed?

The problem also sounds electrically related, although I couldn't tell you whether the way the plug was installed could have affected the coilpack operation.

Goodluck.

[MT]

WOAH :o

[toro126]

my car is back on the road naw... i got a helicoil done from mobile dude action thread repair. i put performance plugs plus the new coilpack. i also installed a hd exedy clutch and machine flywheel and trd thermostat goes sick. but naw atfer all that my car on idle it sits at 1500-1800 rpm.it wont go down.iv checked for vacuum leaks checked all connections, checked cable and throttle body, plus i talked to my mate at toyota.

every says to me to give the computer time to adjust....is this true?

plp tell i should re programe my ecu coz of wat happened to the coilpack.

[chicken]

Ill take a stab and guess could it be the trd thermostat? The engine can't warm up because the thermostat won't let it!

[toro126]

no it happened even b4 i intalled the thermostat.if im freeway drivn say im going at 120 on 5th gear then i put into nuetral the revs drop down to 1000 rpm then jumps to 1800 rpm then back to 1000 rpm so on and so on. it will only go away when i have it in gear.at the lights on idle its sits at 1500-1800rpm.

the funny thing is when i switch the a/c the revs drop down to 1200 rpm then to 1800rpm when thea/c clutch goes on.

[xoom]

i think maybe an ecu reset is in order .......

[SuperDave]

When you take off without any throttle application does the car stall or struggle and you have to slip the clutch for a while? Reason I ask is that the Sportivo requires a small amount of throttle to get off the mark, where as a 1zz doesn't. Who ever did your work may have thought, "thats odd, I'll adjust the throttle cable". When you blip the throttle what rpm does it return to?