WHAT THE F* is happening ?!

Thanks for tuning in to my clickbait title, but its true, i dont know that the F is happening with my Tundra.

Last night, i went through a series of maintenance items, rear diff fluid, oil change, cleaned my air filter, and sprayed down my MAF with a little cleaner....When all the was done I was running low on light but wanted to knock out my spark plugs so I started with the passenger side plug that is closest to the front of the truck.

Changed that plug AND THAT PLUG ONLY, before it got dark and I decided to wait until this morning. I replaced that plug with an OEM from Toyota, double checked the part numbers and the GAP on the plug before I put it in. Tightened everything up to torque spec, old plug came out easy, new one went in just as easy.

Go to start the truck this morning, fires up, but now the truck is vibrating on idle, its significant enough to know something is wrong, Check Engine Light is present, and a Pre-Collision Sensor Warning and Trailer Brake Controler Malfunction are all present. I through hmm, maybe the spark plug is bad, so I took it out, and put the old one back in. Once again, super easy, everything seated fine.

My trusted shop is a 1/2 mile from my place and I drove it there and truck would feel very strange at around 45-50 mph, but otherwise drove fine.

My oil level is perfect, i put 8.5qts in yesterday and I verified that with the dipstick. There is 0 oil leaking anywhere. The coil pack i pulled out looks in totally perfect condition, the wiring harness that plugs into it looks in perfect condition. I have 0 wires nicked or unplugged. The scan tool at the shop read a ignition misfire code of some sort. We attempted to clear the code, but the truck wouldn't allow it.

PLEASE post any and all information you have on this for me, even if its just a hunch or somewhere to look. Waiting for the shop to ring me and see what they have found but honestly super weird. Maybe there's some fuses I need to pull and inspect? Literally everything else looks great visually and once again I only pulled the 1 single spark plug, the rest are completely untouched.

 

Clickbaited for sure.

Sub'd to know the outcome. My first thought would be the MAF. I've read that those are very finicky.

 

Yeah but to throw such a wild amount of codes? And also for it to then read some sort of ignition code. I have had a MAF go back in my 07 FJ. It immediately threw a code, but the code was directly related to AFR ratio or something like that. The code itself pointed my directly to the MAF system, and i knew right away i needed a new one. I swapped in the new OEM, disconnected the battery for 10 minutes and the code was gone upon firing up the truck. Also what gives with every other sensor going haywire....I really wish trucks had fewer electronics.

 

Maybe counterfeit plugs? Did you get them on EBAY?

There are some pretty sharp people here! They are probably going to ask you what specific codes are being thrown.

 

MAF sensor cleaner CRC.

SHOP JUST CALLED. Turns out one of the OTHER plugs had somehow come slightly loose. The electrical connector. I must have bumped it just right while laying everything out in preparation to do the job. It was unplugged just enough to not look like it, but not fully seated. Ill take this as a very weird learning lesson. triple check that everything is seated absolutely perfect before firing up your truck. Glad that's sorted out. It would have been so strange if it had not been something so simple. For those curious it was Cylinder 1, which is the opposite side I worked on, and the furthest back as you look toward your engine. I truly have no idea how the would have came loose since I purposely didn't start on that side since that's the easier one to work on.

 

It got sorted, but nah i got the OEM plugs from Toyota, and after the issue, i went ahead and put back the plug i had swapped anyways so that couldn't have been it. All OEM from my dealer.