'90 E4OD wont shift properly

[Hway]

I have a '90 full size with a e4od transmission.I had it running doing 70 that was 2 years ago. I had to let it sit for a bit because of my surgery, then I took it out for a spin and I can't get it above 35 again.
I have changed parts over time.
I have changed the sensor on the pumpkin, changed the speedo gear, changed o2 sensor, alternator and a few others.
I even had it at transmission shop, they said it wasn't getting enough power but it was good.
Then I hit a bump then it was working right.
However since it sat for 3 months I can't get it running right.

 

[Tiha]

It sounds like it is an engine issue, not a transmission issue?

Not enough power to get enough speed or rpms to shift? Does that make sense.

Or what is it that makes you think it is the transmission?

 

[Jimbo26]

Go hit another bump, that'll git-er-done!

 

[Hway]

It sounds like it is an engine issue, not a transmission issue?

Not enough power to get enough speed or rpms to shift? Does that make sense.

Or what is it that makes you think it is the transmission?

The rpms is going high but will not shift. I thought when I took it to the transmission shop it would be transmission. They said it was good but it was the lack of power. I do know in later models a 3rd brake light would make it go in limp mode, so I checked all of my lights and if they were out, I replaced lights.
I'm not a mechanic but I'm willing to try to fix it.

 

[Hway]

Go hit another bump, that'll git-er-done!

Believe me I have tried that too.

 

[Tiha]

Is your speedometer working correctly now?

At one time there was a lot of talk about the MLPS switch retaining water can causing problems. It is the one under the shift linkage on the side of the transmission.

 

[Hway]

Is your speedometer working correctly now?

At one time there was a lot of talk about the MLPS switch retaining water can causing problems. It is the one under the shift linkage on the side of the transmission.

Speedometer is working correctly.
I will recheck the MLPS switch. I replaced it 4 years ago.

 

[Hway]

Ok, so I found my tester and with koeo I was getting code 56.
I cleaned the maf sensor and checked vacuum lines.
Then I cleaned the sensor on transmission passenger side.
Plus cleaned and rechecked the mlps.
Now my rpm needle is bouncing really high and will not come back down to normal no matter what.
So I ran tester again koeo now I'm getting codes 22, 56, 99.
I did koer getting codes 26,44

 

[Tiha]

Rpm needle is high, so like the engine is actually running really fast? Or just the electronic gauge is off?

High idle is often caused by vaccum leaks. I suppose a bad MAF could have something to do with that.

One thing you can try is start it up with the MAF unplugged, see how it runs.