Recommendation and cold start problems

When it is really cold or humid the truck will stumble or take 3 attempts to start.

I recently hit 100000 miles on my truck what is the recommended tuneup at this stage?

Thnx for any help.

 

Is your truck Flex fuel? It’s a common problem with Flex fuel engines and there are many threads about it

 

This sounds like a classic air/fuel issue with fuel injected engines with a side of less common but also not unusual weak spark.
Do the easiest thing first, check for an obvious vacuum leak hose that's fallen off strange whistling noise, etc.
The next easiest things are to clean the throttle body and the MAS (mas airflow sensor), this is two different cans of cleaner.
If take out the plugs and look at them, if they're gross you have problems, they're just old but look fine replace them with OEM.

Next level is to clean the fuel injectors, go to shop that has the nifty tool that will run 100% cleaner through them.
The same shop should have a high quality scan tool that can see what the computer is doing with the air fuel mixture while it's running and should be able to give you a good idea of what's going on (i.e check the MAS while it's running).

Don't want to go to a shop to clean the fuel injectors, run the fuel down to 1.4 tank put in a couple bottles of cleaner the run it at down as low as you dare without running out of gas on the road. If the OEM MAS for you truck is less then taking it to a shop for diagnosis, just replace it but only use the Toyota OEM MAS, aftermarket once are nothing but trouble.

You're staying on top of the regular maintenance oil/filter and air filter but just in case check the air filter sometimes things happen suddenly to it even when it's changed on a regular basis like a dead squirrel or even several live mice. Rodent urine is not good for a MAS sensor.

 

Try a bottle of BG 44K it is good stuff for a long term cleaning of the fuel injectors and fuel system. You can purchase it at Napa stores. $32.00 approx per bottle.

 

If you have not already, it is time for spark plugs for sure with 100k. Throw a new air filter in there while you are at it.