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Crumz
11-08-2010, 10:02 AM
Mostly stock S14a SR20DET 208,000kms

2 Weeks ago came up the hill on my way home, was giving it to the car the whole way so as expected shit was 'warm'. Dropped a cylinder round corner from house, no biggie, nurse it home, pull into driveway. Popped the bonnet to check with car idling, then she stalls.
Soon found I had no ignition. Car would crank, but no indicators, windows, dash lights etc.
Had a check around and called my uncle (auto sparky).
Discovered immobiliser circuit board had split, loosing a contact (the one that feeds ignition). Fixed that, started car to find mis.
Found number 4 misfiring, expecting it to be a plug, I whipped the coil pack out only to find that it's insides had become it's outsides. Cooked, hard.

Car sat until I got another CP yesterday, took it for a quick, hard drive, no issues.
Went down the hill just now, coming back, not driving as hard, but still above 4500rpm changes, drops a cylinder again. Again get her home.
Again have cooked the CP, hard. f##ker was smoking for 10 mins after stopping (I believe that may have been the 5+ minutes of driving with it already dead). Again was cylinder number 4.

So. What causes a CP to fry? I could have said yeah these are old, must be the issue, but both being number 4, and a newer one in, it's something to do with that cylinder, either the wiring or the way it's sitting.

Possible it's rubbing on the plug wall and shorting that way?

Possible the immob is f##ked and causing shorts? Autowatch alarm system. Thinking I might just delete it from the car, but need a few tools first.

Anyone come across anything of the like before?

Anyone near Roleystone got SR CPs?

alexinperth
11-08-2010, 10:55 AM
Maybe if the CP is held in the charging state for a long time, it overheats? Thing is, it must be misfiring the entire time it's stuck like this.
The cause of this must be a failed coil driver inside the ECU, or a short in the wiring loom.

180SXTCY
11-08-2010, 11:28 AM
Adam check to make sure the coil pack harness is earthed correctly and look for shorts. I think I've got a set of s13 coil packs in the shed.. Pretty sure they r going to be the same as s14 ones

180SXTCY
11-08-2010, 11:28 AM
Oh btw wat ecu is in ur 14

Crumz
11-08-2010, 01:33 PM
John, they are the same, I've confirmed that. If you could drop them at mine I'd be ever so grateful, fly out for work again tomoz.
ATM ECU is still stock.

harness is a definite maybe, but at $220 (S15 price at least) I don't wanna bother, specially considering it would only be getting 3 more drives before engine change anyways.

Alex, definitely not misfiring the whole time.
Ignition module is on my list as possible as well.

180SXTCY
11-08-2010, 01:49 PM
adam pm me ur number and depending on what time i get home tonight ill go down the shed see if i can find them and also the harness and you can give that a shot.

datsqik
11-08-2010, 06:52 PM
Ive seen one where someone had played with some wiring when they installed a boost controller causing the wiring to melt on the exhaust. This wiring was connected to the igniter.

alexinperth
12-08-2010, 10:54 AM
drops a cylinder again. Again get her home.

This was probably long enough to cook the coilpack. That's what I meant by "misfiring the whole time". They're only designed for a short duty cycle, and having them charging 100% of the time will kill them.