04 Tundra won't relearn idle after battery change

250K miles. I changed the battery and as usual it would not idle right away. I have changed out the battery 4 times in the last 12 years and it has happened each time. It usually relearns to idle after a 15-20 minute drive, but not this time. I drove it for about 45 minutes. I checked for codes and it passed. I also held it at 500-1000 RPM for about 5 minutes both in neutral and idle and it did not relearn to idle. Any tricks at this point or start trouble shooting by cleaning the throttle body, MAF sensor change, etc.

Thanks

 

Ive always just drove the truck. Seems like it will dle very low for the 1st 20 minutes. Then steady driving for 10-20 minutes, then it's back to normal idle RPMs.

 

@Sea Goat What is the truck idling at?

 

it won’t idle unless I slightly push the gas.

 

@Sea Goat "Turn the key to the second detent (the actual run position, not start position) and let it sit there for about a minute. It may need to relearn the throttle stop."

 

Might be time to clean the throttle body...

 

@Sea Goat

You should put your truck info in your profile (year, engine, transmission, 4x4/4x2, cab layout). There are major differences over the run of 1st Gens: two versions of the V8, two versions of V6, two versions of auto trans, three cab layouts, etc.)

 

I've not had to do this on my Tundra, but on my old truck I'd have to hole the idle at 2000 rpm for 2 minutes. Might try holding at a higher RPM?

 

I was going to say this also. You may also want to make sure your last battery wasn't bad, by carrying it to the store and having it professionally tested. But in general, the symptoms you describe, i.e. "Every time I cause my ECU to un-learn and reset how it operates, i.e. I take it off battery for some time, the truck runs rough as fuck", it's indicative of the truck not being able to run with baseline parameters it would use, because something inside the system isn't right. i.e. your throttle plate maybe can't close to the amount necessary to function using baseline values.

You don't need to remove the TB to clean it.
DO NOT use anything except TB cleaner specifically for the job, CRC makes a great one.
DO NOT spray cleaner directly into the TB, spray it into a shop towel, then wipe in/around/behind the butterfly to get stuff.
DO NOT let the butterfly slam shut.
Remove the negative battery cable BEFORE you start, so you can force the computer to re-learn.

If you make one of those DO NOT items, you may end up fucking up more than you fix and really screwing yourself. If you need a video ... 1st one is without removing. 2nd one is with removal. These are both highly valuable YouTube channels if you have a Toyota.

https://www.youtube.com/watch?v=3B-a8WJtd8w

https://www.youtube.com/watch?v=HUG_4864ovU​

 

^^^THIS^^^

 

I’ve don’t that for 5 minutes twice. I’m going to clean the TB. I’ll report back.

 

Good stuff. Thanks.