91 toyota pickup.. stumbles on acceleration

[skerfer22]

i have i 91 toyota pickup 22R 4wd 250,000 miles with regular mainteince. When cold runs fine but when it warms up it wants to stumble during acceleration through the gears... Checked fuel pump pressure good. changed fuel filter. Done tune up and adjusted valves. Idles fine. After it stumbles a little bit it seems to clear up until the next gear then the same thing happens.

 

[2ndGenToyotaFan]

Is it a 22R (carbed) or a 22R-E (fuel injected)? Just double checking. 91 was a little late for carbs, but not unheard of.

 

[2ndGenToyotaFan]

It's fuel injected, he PM'd me.

Check you TPS:

http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

Air filter, check your spark plugs and let us know how they look. How long since a tune up? Could be the fuel filter, but that's a pain to change as there is not much room in there.

Also the AFM:

http://www.4crawler.com/4x4/CheapTricks/AFM/index.shtml

Not really likely that it's the afm but it could be.

There's a good start for ya!

 

[Jukelemon]

The hot/cold issue is Key. I will check the FSM for you.

 

[Jukelemon]

States in order for hesitation upon acceleration

1- Check Brakes ( :
2- Check clutch for slipping
3- Check EGR valve
4- Check TPS

 

[2ndGenToyotaFan]

Out of that list the EGR is the only thing that changes with the engine hot/cold. I'd start there.