08 Tundra wont run once warmed up. Any ideas?

Hello all
I had my tundra die on me while driving one night. Couldn't get it started back up. I had it towed back to the house. I had trouble with battery earlier in the week, but was able to charge it. So I replaced the battery thinking that might be the issue, but it didn't help. Still wouldn't start. I added some gas to the tank even though the gauge was reading 1/4 full. Was able to get it started. but it died again once it warmed up. I replaced the fuel pump. Same problem. I also replaced the spark plugs to no avail. I did find oil in 3 of the spark plug tubes on the left side. Not sure if it's related or not as I've heard that's a common problem. Hoping someone might have some ideas. Any help would be appreciated. Thanks.

 

Clean the throttle body and mass air flow sensor. I had a 4Runner I replaced the battery on and it wouldn't stay running afterwards. Cleaned MAF and TB, let it relearn the idle, runs like a champ.

 

How much oil were in the spark plug cylinders? Whats your battery voltage at once it warms up?

 

Alternator are the culprits!!!! See forum on this issue. Especially if you up in the 150+K miles

Faulty plugs would give a rough idle before shutting down

 

Yes, alternator could be the issues. Slipped my mind.

 

I will check the MAF and throttle body.
The battery sits at about 12.5 when warm.
I think I checked the alternator a few weeks back but I will check again to make sure.
Not sure how long it should take for the computer to relearn the idle.

 

There was a bit of oil on one plug and much less on the ones on either side.

 

sediment in the gas tank?

 

Nope. No sediment. It was clean.
I actually just got it going. After replacing the fuel pump, I hadn't let it idle for long enough. I let it go for about 10 minutes and it upped the idle. Running like a champ now.
Thanks for your help guys. Super excited.

 

Alt should be about 14.2ish (or close to it) when running, 12.2-4 when not running. If your engine is running and you are at 12.5v and you said youve replaced the bettery...most likely yer alt.

 

Do you have codes stored in the ECM?