Possible blown head gasket?

I might try replacing the coil pack before I take it to my mechanic. That sounds like its an easy fix if it's the problem

 

Switch coil packs with the cylinder next to it to see if the misfire moves. If it does your coilpack is bad if it doesn't next switch the plug. If the misfire still doesn't move then check injectors and last compression. Good luck I hope it's nothing major.

 

Head gasket leaking fuel? Fix the miss fire before you kill the catalytic converter.

 

This doesn't sound like a head gasket to me. I would go with the Coil Pack or Fuel Injector stuck partially open.

Do not drive it with the fuel in the oil of with the injector leaking as two very bad things can happen: Hydrolocked cylinder resulting in bent piston rod or worse... and the fuel washing the lube off the cylinder wall and causing scoring and wear then burning oil and a loss of compression.

 

I'm looking at coil packs and it looks like there the same coil packs between the 6 cylinder and the 4 cylinder. Is this correct? I don't wanna order a 4 cylinder coil pack by accident

 

Test it all first before you just start changing parts and chasing the problem. Yes all the coils are the same. That is how you can swap them around to test to see which one is bad if any.

 

A quick check for leaking spark: In a dark garage, mist water over the coils and wires. Look for arcs.

 

before you spend a dime on parts, do the troubleshooting legwork, if you just start buying parts, it could end being rather expensive...

coil packs aren't really cheap, if that is where you plan to start...

 

I've got the same code on my 05. And I've been noticing it idling rough at startup for 20-30 seconds. And whooshing coolant going through the heater core right afterwards whenever it does it. And I can see a trace of white smoke out the tailpipe when it's idling rough. Searching around on the code it does sound like a blown head gasket in my case. I just bought it so I'm hoping the dealer will do a good will repair. Otherwise I'll likely do it myself. Certainly wouldn't be my first head gasket job but it would be a first on something with variable valve timing. Could be interesting...

Of course I have yet to hook up my leak down tester to see if it blows bubbles into the coolant. Haven't even pulled the plugs yet. But both were changed out within 5k miles of it being traded in. Makes me wonder.

 

I checked the coil pack and it didn't work yesterday then today I pulled the spark plug and it was awful. I replaced it with a brand new one and the code immediatly went away

 

Old spark plug on the bottom out of the misfiring cylinder and the brand new one on the top

 

The plugs on the 4.0L are due for changing every 30k....

 

dat gap

 

I haven't had the truck longer than 20k miles and I assumed that the dealership I got it from would have replaced them

 

psh. don't you know, the fuel is pre cooled through the coolant system before it hits the rails. that's how the 1gr gets its ability to run 87 at 10:1.

the head-gasket acts as the heat exchanger

sorry op I have to poke a little fun at your mechanic. used motor oil ALWAYS has a bit of a gasoline smell to it as the two occasionally intermingle when the piston is on its downstroke. if your rings were absolutely perfect, it would never happen, but they aren't and never will be. fuel and sub-sequent combustion are actually the number one reason for having to change your oil. . . . . .the more you know

I am super glad It just happened to be a bad spark plug, and a bit surprised nobody mentioned it before you found it

 

Getting the engine to operating temp burns off most of the waste fuel. The oil may have a faint odor. With a misfire, more raw fuel is being dumped in. The oil will reek of fuel. It has been noted before.

 

You only going to change one? They were shot 5,000 miles ago.

 

Not to mention coolant in the cylinder washes down the cylinder walls which hurts the ring sealing and allows more fuel to pass through. I had a tiny crack in the combustion chamber of the #5 cylinder in my old FJ40. Never saw any smoke (well not white smoke) but the oil smelled like gas and it burned oil like crazy. Used very little coolant and with a leaky radiator anyhow I never figured it out until I rebuilt the engine a few years later.

The more I read and with what I have noticed on mine I'm pretty damn sure my 05 has a blown head gasket. It's intermittent though. Started it up this morning to put my Capri back in the garage and it was perfect. Yesterday it stumbled and pushed a little white vapor out the tailpipe at every startup. And whenever it does it I can hear air bubbles in the coolant passing through the heater core as soon as I start driving it. Yet it runs perfectly fine after about 30 seconds. I'm crossing my fingers the dealer I bought it from will cover it. Otherwise I'll be buying some specialty tools and digging in. Thankfully I noticed it when (a) I have a slim chance my 30 day/1000 mile warranty I got might cover it and (b) I have 2 other cars to drive until it snows. If this happened in the winter I would be seriously hosed. Both my other cars can't even make it out of my driveway in the snow.

 

i just thur this with my sons truck, 02 prerunner w/285k. similar codes as yours. i was thinking head gasket too. but i ordered new coil packs and plugs 1st. do the cheaper things 1st. truck sounded like it was running on two cylinders and i thought it was toast. i replaced the coil packs 1st. ran like chit, replaced the plugs and she ran like a champ again. my son wanted to sell the truck before fixing it. now he is keeping it. gl with your truck.