Trans question

[Johnny Wayne]

I have a question about a trans issue. When i am driving between 45-55 in overdrive it feels like it is surging slightly. I have owned it for about 3-4 weeks now. I have not changed the fluid yet but I am planning on it over the next few days.

 

[miesk5]

I have a question about a trans issue. When i am driving between 45-55 in overdrive it feels like it is surging slightly. I have owned it for about 3-4 weeks now. I have not changed the fluid yet but I am planning on it over the next few days.

yo hondo!

go ahead & hange da fluid & filter first.

get Codes checked at AutoZone for free; make sure they do both KOEO & KOER tests. KOER test requires eng at norm op temp;

or diy

Self Test & Connector Location & pics, Bronco & Ford BEST PROCESS WITH DIAGRAMS! Source: by Ryan M

&

Self Test - KOER Self-Test, How To Run a Source: by Ryan M

Guesses:

Could be the Throttle Position Sensor (TPS),

worse cases as a guess;

Excessive variations in slip (engine speed surge) across the torque converter clutch

Excessive torque converter clutch engagement error

 

[2NDTOUR89]

Try this, disconnect the vacuum line going to the EGR, plug it and try it out. It could be a defective EGR valve or position sensor.

 

[Broncobill78]

a 90' huh ? any chance you're sporting an AOD ? Those puppies have a habit of stretching the Throttle Valve cable, once the throttle pressure gets out of whack surging is one of the symptoms but more importantly having screwed up throttle valve pressure cooks the tranny. My 88' has one, your 90' may not. Unfortunately that's about all I can add to the discussion unless you swap to a C6 & then I can help but why the helll would you do that ?