2004 nissan 2.4L blew out #3 spark plug boot

[Niti QX4]

Symptom: 2004 Xterra 2.4L blew out #3 spark plug boot

Situation: was driving on the highway after filling up the tank. Lost power and shut off. After failed restart attempt, opened the hood and found the #3 spark plug wire missing from the plug hole.

Found the plug wire and boot hanging down in the engine Bay.

Reinstalled the plug wire and still no change in being able to start the engine. It turns over OK, but it seems to have no ignition.

Has any one else had this Occur, and is there a chance this damaged the ignition coil because the spark had nowhere to go?

[VStar650CL]

It is possible for an open wire to overheat and kill a spark coil. It depends largely on how long it was run that way, because the retained heat from being unable to discharge is what kills it.

The only things that can really "blow" a plug wire loose are a) a very loose spark plug combined with (or causing) a backfire, or b) a combination of a plugged PCV with a bad skirt seal in the valve cover, creating pressure in the crank that's conveyed into the plug recess. If the #3 hole isn't full of oil, I'd be inclined to think (a) is more likely.

Given the circumstances, I'd advise popping the distributor cap to see if the shaft is turning. You may have dropped the timing chain.

[Niti QX4]

I found a “loose” spark plug, so that makes sense for the pressure buildup.

I’ll check the distributor next. Thanks!

[Niti QX4]

Well, looks like the coil is smoked. It appears to have jumped in one place for sure, and possibly a second as well.

[Niti QX4]

By the way, this is a CM1T-227 coil, but amazon keeps sending me to CM1T-230 instead.

Just to confirm with the more knowledgeable here; the 4-cyl (2.4L) uses the 227 and the 6-cyl (3.3L) uses the 230?

I ordered the 227 since that is what was in it, and it was working before the plug boot went flying.

[VStar650CL]

We generally call those deformations "warts", and they're caused by overheating of the coil primary, the driver FET (power transistor), or both. When a plug wire comes loose it's generally the primary windings that overheat, and it looks like that's what happened to yours.

Nissan never sold those coils separately to my knowledge, but I'm pretty sure the 227 is the right one for all the KA24DE's.

[Niti QX4]

I would like to see what the difference is between the 227 and the 230. I would guess a size difference to compensate for the six firings versus the four.

(ie: The winding saturation point due to the frequency change; 6 vs 4)

https://www.electrical4u.net/electrical ... aturation/

I'm guessing here, but if saturation is the issue for the change, then a 6 cyl coil could be used in a 4 cyl, but not the other way around. BUT only if it would physically fit into the distributor.

Are the distributor bodies the same size for the 2.4 and the 3.3 such that either coil would fit?

[VStar650CL]

You'd have to measure, but I believe the base on the VG dizzy is a bit bigger than the KA. Not that it necessarily affects which coil will fit, unless there's a mechanical design difference.

Tsat isn't generally an issue for engines running at street speeds. The time to reach the knee point for almost any automotive coil is way faster than the engine can spin. They all run around 4~10 milliHenrys, and even a 10mH coil has a reactance limit of 1.6KHz. That would equate to 32,000 RPM for a 6-cyl engine. Even if you did somehow exceed the coil's Tsat, what you'd see at first is a drop in spark energy and not a misfire, because you'd simply be discharging it partway up the charge ramp. Keep in mind too that we're not stuck with a fixed dwell like an old points ignition. Any engine with a PCM or spark module can (and will) vary the dwell time according to the demand.

To sum up, it's probably more a matter of whether the 227 and 230 will fit in the same hole. I'm guessing they don't, even though they look similar.

[Niti QX4]

Just adding a "Summary" for the search engines:

2004 Xterra 2.4L, 5 Speed - Crank, No Start (SOLVED)

SYMPTOM: Crank, no start.

SITUATION: 2004 Xterra 2.4L, manual, blew out #3 spark plug boot. Was driving on the highway after filling up the tank. Lost power and shut off. After failed restart attempt, opened the hood and found the #3 spark plug wire missing from the plug hole.

Found the plug wire and boot hanging down on the side of the engine.

Reinstalled the plug wire and still no change in being able to start the engine. It turns over OK, but it seems to have no ignition.

FINDINGS:
1. The plug boot blew out due to a slightly loose spark plug
2. The crank, no start - is caused by a burned out coil. When the plug boot blew off, the spark had no where to go so the coil overheated and failed.
3. Replaced the coil, the cap, and the wires for good measure.
4. Works fine now.

[VStar650CL]

[Q451990]

So which coil did you end up using?

[Niti QX4]

CM1T-227