Multi-cylinder misfire when cold (2010 5.7 non-flex)

I have a very strange problem. Recently on my 5.7 non-flex fuel w/ 97k I had to fix my starter as the solenoid went out (click but no start). I had my OEM starter rebuilt by a reputable shop that I’ve used before for Toyota starter repairs. Did the whole remove the header and exhaust process in order to do the work. Put it all back together and truck fires up with no issues and remains seemingly perfect for a week. Now the new story and I’m not sure if this is related. One cold morning I fire up and get 4lo/trac/engine lights flashing. Read codes with my Bully Dog programmer, p0300, 301, 303, 305, 307. Let it run a couple minutes. Shut it off, restart and it runs absolutely perfect. Clear the codes and chalk it up to the starter repair the first time. 4 days later same scenario, EXCEPT this time all the EVEN cylinder codes this time. WTH? This scenario has happened about 4 times in the last 2-3 weeks. Only when the motor and climate are cold in the morning. I’m in N FL so the temps have been fluctuating pretty widely. When it happens, it’s throwing codes for different cylinders every time. Once it only gave P0300. All the routine maintenance is up to date. Have not replaced spark plugs yet and figured that’s where I’ll start this weekend. I’ve searched the forums but seeems all threads are only about one cylinder, maybe two, never alternating all 8. Please help!

 

Do a tune up, run a bottle of fuel injector cleaner through the tank, what brand of gas are you using and what octane?

 

91 octane and ran a bottle of seafoam a few days ago as someone suggested the same idea. However, the thing happened yesterday morning. Maybe plugs will be my solution.

 

Changed the plugs last weekend with new OEM. Made it 5 days before I got the same codes. P0300. Truck is running perfect still. Help!!!!!

 

sorry to hear this...hope you get some ideas soon...this sounds like an odd one.

 

Soooooo, turned out to be a bad Crankshaft position sensor. Swapped it out about a week ago and zero issues since. Hope this helps someone I. The future.

 

You ever get codes thrown from the Crankshaft Position Sensor itself or just the misfires?

It seems like I am having the exact same issue with a 2010 5.7L that I just bought off a used lot. Cold weather startup sometimes (no real pattern) runs rough with CEL flashing, let it warm and up shut off, restart and everything is perfect. Random P0300, and P0300x individual cylinders (again no pattern).

Seems like I might have inherited a bigger problem that I bargained for, I am really hoping this is the solution. The local mechanic I had do the basic plug/coil look over (replaced a few of each that looked worn) said to ask for money back/run away. Called the last Toyota dealership service location on Carfax in 2017 and they said the same thing, not super encouraging.

 

So I'm having the same issue. My starter went out. Doing some trouble shooting I changed my CPS and then did the starter. I've got A solid CEL, blinking 4lo, blinking VSC off, and a solid Trac control light. I've changed the gas cap, ran 2 bottles of heat through, 91 octane all to get a random cylinder misfire. Some days it will be 300, 301, and 305. I could clear all those to get a 300, 304, 307, 308. Some days I get them all! I'm going to put the old CPS sensor in and let everyone know what's going on. Truck runs fine. Just get the lights and codes.

 

When my starter went out, I got the CPS code, swapped it with an Import Direct part. Long story short it was the starter. Another thing to consider is the wire harness that travels in there with the starter. If any wire was damaged your issue may be there, what sucks is the space in there.
If you need more assistance consider posting a new thread.

 

Well it was the CPS. As soon as I put the old one in, all the lights went off and no random cylinder misfires. The bad CPS sensor was bought from Oreillys. I hope this helps someone down the road.

 

I bought a similar one 5 years back, I'm starting to have failed starts. No clicks no nothing. May be time to go back.