Random Misfire Cylinder #4

[JeffHicks]

I continue to track down weird little issues with the crippled '04 V70 I bought...

On cold & cool starts, it will stumble a bit and has a miss. After running for several seconds it will begin to hit on all 5 cylinders & run great.

Finally I got another misfire code. Cylinder #4 - one of the cylinders I've had a previous random misfire on. This is the cracked wire cover I found.




Now... Would a nice coat of Liquid Tape do the trick for this wire? Or would you recommend replacing it entirely? Your thoughts?

[abscate]

Jeff - you might need to cut that and splice it back together firmly to make it work, not just tape it. Solder would work too.

[JeffHicks]

^ Thank you!

I will likely end up doing that in the long run (specifically, when it's no longer winter!). But for the time being I decided to coat it good with "liquid tape." For the next month or so I have no driving to do, outside of puttering around town. That should be a good gauge of whether or not I've solved the riddle.

[abscate]

I think the 2004 and 2005 wiring are the same on the coils...

Note the different color wires are the control signals - grounded at the ECU to fire the coil.

The Green white supply 12 VDC to the coils.
Terminal 2 provides fire diagnostics to ECU ?
and the SB wires from Terminal 3 are grounds.

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[terryjr]

haha, dont say #4 misfire around a Subaru guy, sure way to give him anxiety. Almost always means a cracked piston ringland

[JeffHicks]

haha, dont say #4 misfire around a Subaru guy, sure way to give him anxiety. Almost always means a cracked piston ringland

Head gasket.

HEAD GASKET!!!!!

[terryjr]

ya thoise too. I have about 16 head gaskets hangin up in the garage. Only one or two actually blew the rest were ringlands and bearing failures