From my own experience I'd do as HeyYou suggested, (PULL) the throttle body off and clean it as the DIYs tell to clean it, don't just spray cleaner down the TB. Pull all the sensors off (MAP, TPS, IAC) so they don't get messed up and carefully clean off the carbon and gunk, paying special attention to the IAC orifice . Disconnect the battery first thing, get a new TB gasket to install when cleaned up, do the start up procedure for the PCM relearn and see if that doesn't solve the problem.
The other thing for the late shift issue is when is the last time your transmission was serviced...( oil, filter and front/rear bands adjusted?) with the throttle body cleaned up the sensors may be expecting certain spec values from those too, just a thought...

 

Yeah tomorrow I'm planning on the full she'bang cleaning. Especially the IAC and TPS orifices. Also was thinking heavily on the tb gasket to at least see if it's split anywhere but then noticed they're only $2 haha amazing.

Going to change the oil/filter 1st thing in the morn at shop before reclean and Seeing as she's about to hit 100k I am thinking about a tranny flush/service with new gasket. She is clean and pink when I check the fluid today though. But what she is doing now is just higher than before. She was going high before too. I think I just try not to think about the tranny because I'm afraid of the outcomes. I love my van and get scared lol.

Ty JFloors really appreciate the input!

 

Do NOT flush the trans. Fluid/filter change, and band adjustment IS a good idea though. (just drop the pan, do what ya gotta do, and put it back together., no other machinery involved.)

I would take a good hard look at the TV cable, both ends. Sounds like it is sticking open, so the trans thinks you are really romping on the gas, and adjusts shift points accordingly.

 

HeyYou. It was the effing!!!!! TV cable. It was corroding and not giving enough slack (new england weather)

But also turns out it wasn't IAC or TPS but Plenum. I checked some other threads about same issues and saw you mention PCM a few times. I did volt checks and Pcm check all was good. I took TB off again and looked into see oil pooling and vacuum definitley pulling. So it's getting a new plenum today.

You da' man and Jfloors too. For now on I am using rockauto as well great freaking prices and OEM.

thanks guys!

 

for others who may not know what the hell is going on after all these fixes

 

Yep, good call for sure HeyYou and glad wasn't anything more for you TallmanLilVan.
I'd had a shifting problem a year or 2 ago where 2nd to 3rd would go to high rpm with no shift until letting off the pedal, also going up a grade on the highway would shift down to 2nd at 60-65mph by barley giving some throttle to keep speed on the uphill. Had done the TV cable adjustment and the front band adjustment on my '99 van, which helped alittle bit, but ends up the Governor pressure sensor/and solenoid replacement and a fluid (ATF+4) and filter change is what cured the shifting issues. Just something to keep in the back burner if you ever experience those type of symptoms. Glad to hear you're working out the problem