Misfire codes question

Hello,

I’m hoping I can get some guidance on what I should look for or test out. Here is what happened;

I own a 09 V8 with 200K+ on it. Recently changed my driver side axle. In the process of changing it I got some lights turned on. A SOLID CEL, BLINKING VSC OFF and SOLID ATRAC. Upon startup and seeing those codes i didn’t notice any symptoms, maybe a bit of a shake while parked. I then did not drive or turn it on for 5 days. The days leading to this were cold and rainy. Once I completed the axle change, I turned the vehicle on. I did turn it on with high fan speed and high temp. This is because I also changed my upper radiant hose and lost a lot of coolant in the process. This was done because I had noticed a leak coming from the worm clamp. Now at the startup, I immediately saw a large cloud of white smoke from the exhaust. To me, this did not smell like anything. I even walked into this cloud but could not identify an odor. I then test drove it and had no issues. Drove to an auto parts store for code reading.

Scanner read misfire on cylinders 2,4,6. Checked the spark plug (first one on the right when facing engine) and saw the tip was black. There also seemed to be a bit of gunk(?) inside the coil at the top where the coil meets the plug. These are Denso Iridium long life plus, 0.44” gap that were installed by me 2 years go. So less than 100K mi. Guy at the store stated this was a ignition coil issue and i should change them all out.

Wanted to see what ya’lls thoughts are on this? I have read this could be a head gasket issue but i did not notice a sweet smell. On the drive back I forgot to check if white smoke appeared again but the drive was smooth. No other symptoms were noted.

Any help or info is greatly appreciated.

 

Wanted to give an update. Turned the car on today and had zero white smoke. Oil in dipstick looks normal. Radiator cap had some coolant and it looked fine. Coolant reservoir was empty but thats because after spilling all the coolant in the lower radiator hose, i did not fill up the reservoir. Guess the vehicle “drank” it up and just needed a refill. I will saw the inside of the reservoir was dirty. There was some deposit at the bottom. Looked like dirt maybe and the little coolant that was in there was not clear. Washed it out and put fresh coolant in.

 

For the misfires, pull all the coils and inspect them for any cracks on the body that reaches down to the spark plugs. If you find any with cracks, replace those. You can get Denso coils from rockauto.com and they should be cheaper than going to the dealer. Denso is also OEM for Toyota. I agree with it potentially being a coil issue but I wouldn't change ALL of them unless they all shows signs of cracking on the tubes. You can also move the coils around to different locations and see if the misfire issue follows the coils or not.

Head gaskets are not a common issue on the 4.7L V8 at all, so I really doubt that is the problem. The V8 is an aluminum block with cast iron heads, so the heads are not prone to warping.

Try not to use worm gear clamps, especially for the radiator hoses. Buy new OEM squeeze clamps/constant tension clamps from Toyota. They seal much better and are more reliable. They can be reused but I would replace them after a couple hose changes. Personally, I'd replace them whenever I do timing belts as I do new hoses at that time as well. Just good measure.

The coolant reservoir is there to provide additional coolant to the system as every thing cools down. The system will suck coolant from the reservoir as needed to maintain the level in the radiator. Make sure the reservoir always has coolant in it to the "Full" line and you should be fine. The sediment you saw in there is normal and from the cooling system. Washing it out is a good idea whenever you are servicing the cooling system.

 

Yes I will check each coil for any defects and replace. I did jump the gun a little a buy a pack of coils by Walker. Might return those and just buy OEM ones that I need. Also bought Denso plugs so hopefully this is what fixes the codes. In the case of the coil that I did check, there wasn’t a crack but there was some gunk. Is that a sign that it should be replaced as well?

ok so about the clamps. I did buy OEM spring clamps and could not for the life of me figure out how to fit them over the hose! I bought Gates and it did not just slide over. Of course after putting the worm clamp back on I saw that there is a special tool to help with spring clamps. Will try again because these worm clamps have been a nuisance. The “old” hose I replaced was maybe a year old and had no tears in it. Was just that worm clamp causing leaks during temp changes.

As for the reservoir tank, thanks for the explanation. That helps answer some questions. Wasn’t sure if maybe the dirty coolant was a sign of something serious.

 

The OEM spring clamps should come locked open from the factory with a little metal tab that you have to pull off after you slip them over the hose and are ready to clamp it in place. Otherwise, Knipex makes some special pliers for squeezing open spring clamps like that. You can find them on Amazon.

Gunk on the coils could be just about anything. Likely some left over dielectric grease or something of the sort. Clean them off and they should be fine. You can use q-tips to clean inside the boots too if needed. Just soak the q-tip in a little brake cleaner and swab away.

 

Well i just checked the 4 coils on the right side of the engine (when facing it) and they each have large cracks along the barrel. The one furthest from the bumper looked significantly worse and had some brownish powder/coating. All look to be original parts, 09 Toyota with over 200K miles. So safe to say this could be causing the misfires? Probably best to just buy 8 new coils. Looking at OEM prices at rockauto is nuts!

 

Yeah, I would replace all 8 if it were me. I actually did just that last year, replacing all 8 on my 2003, somewhere around the 340k mile mark. Denso from rockauto.com aren't cheap, but they are still cheaper than buying OEM from Toyota and as I said, Denso IS OEM for Toyota.

 

Well i changed all my plugs and coils. All 8 coils were cracked along the barrel. Plugs looked fine but i still changed them anyways, they only had 11K miles on them. Codes have cleared and stayed cleared. Thanks for the tips and advice!