No acceleration

[tate22]

Any ideas why I wouldn't have any accerlation on the highway once in OD? I can put the pedal down and there is nothing. Even when I down shift to fourth there is a little but not much. Runs good other wise.

 

[JerryC]

Post more details on the rig.
Trans, lift, gears, tires, etc..

I this a new problem?

 

[tate22]

'89 E.B. All original , 2.9 ,manual 5spd, manual transfer case with manual hubs. Repaired a/c. Replaced front and back brake components, power steering pump, fan, & radiator over the 4 years I have owned it. 140k on it now. Acceleration problem since ownership. Just is nothing there when need it in certain traffic situations you need to avoid. I had a '90 XLT in late '90's early 2000's with out any issues except rusted through 1/4 panels and no a/c.

 

[tate22]

Hoping to some ideas before settling on taking it to mechanic. Other then that it runs great with good gas mileage.

 

[JerryC]

Have you done basic tune up work on the engine?
They aren't powerful to begin with and it is shaped like a brick so having it in good tune is a must.

Tune up, check/clean/replace the IAC, ACT, MAP, etc...

The catalytic converter can clog up, that would kill the power.

Could just be the gearing is too tall and if you have bigger wheels and tires then overdrive might just be too much for it.

 

[3rd Petal]

Honestly, it's probably just the nature of the beast. Especially if it has 3.45 gears, and is getting worn out from all those miles. When I had the stock 3.45's in my B2 with a 2.9 and 5 speed, all overdrive was good for was going downhill or on level ground. Any incline or to pass required 4th, or sometimes 3rd gear.

Like Jerry said, I'd recommend a good tune up, and if you live in an area that doesn't have smog laws, punch out your catalytic converter, or at lest make sure it seems to be flowing decent enough

 

[JerryC]

To me one indication of the Bronco II's intended speed range is what the mph is at 12 o'clock on the speedo.

On my 88 it's 45mph. LOL

 

[tate22]

Hey guys did everything you guys suggested. No change. I'll wait for the weather to warm up for the converter check. 3rd your description of overdrive is on the money.

 

[JerryC]

Here's a way to check the CC without using a wrench.

https://www.youtube.com/watch?v=d-jp1IIJVVk

You just need a vacuum gauge.

 

[tate22]

Cool,Thanks Jerry, I'll check it out.