Stubble when starting

I have a 2012 tacoma with a 4 cylinder engine. When trying to start the engine, it sometimes stumbles during cranking till the engine fires completely. A couple of times, the engine just kept turning over till I lightly pressed on the accelerator and the engine would fire. I have 97000 miles on the truck.

 

Have you cleaned the throttle body?
Checked that fuel fuel pressure holds with the engine off and builds quickly when cranking?

 

The throttle body looks perfectly clean. I have not checked the fuel pressure.

 

What other diagnostics have you done? Did you try replacing the spark plugs?

 

I changed the sparkplugs even though the old ones were still in great condition. The fuel rail does not have a schrader valve for me to check the fuel pressure.

 

I wish I could help more, it's really hard to say. There are so many different reasons it could stumble...

I had a stumble and long starts until I replaced my coil packs and vvti solenoids with after market ones. So basically I concluded it was some kind of spark issue.

 

You have to have a tee adapter to check fuel pressure.
Something like this.
https://a.co/d/6Xu86lK

 

The throttle body may look clean from the outside but what about the inside? Hold the plate open with the handle end of a screwdriver, get some cleaner on a rag and clean it up in there. Sometimes I'll even remove the TB completely to flip it over and clean it better

 

I’m having very similar problems. I’ve already changed spark plugs coil pack and it ran good for about five maybe 10 miles then I went from just having a misfire, but having a rough idol to losing all power and anytime I would try to give it gas it would completely kill. Sorry this doesn’t obtain to where you were trying to go with it, but I can’t figure out what to do next

 

I have had my throttle body cleaned and have had the fuel pressure checked. When fuel pressure was checked, my truck was starting fine at the time and was holding pressure. The engine stumbling is much worse when the temperature outside is hotter. When cooler temperatures, hardly notice the initial stumbling.