element138

My first post on yotatech so, bear with me...

Mine is an '86 4wd with 22rec and automatic trans.

I notice a while back that the wire which connects to the throttle position sensor was disconnected and thought it was odd, so i plugged it in and as i began to drive, the truck began to lunge forward then the power would drop entirely (without stalling). this lunge-drop would repeat consistently every 2 seconds as i drove. so, i pulled over and disconnected the sensor and it's back to normal.

I'm wondering what might be causing this, if i should order a new sensor or what? It's strange to me that, with the sensor completely unplugged, the truck drives normally. I should also mention that there are a number of yellowish plug ends which lead to nothing (maybe someone disconnected something before I owned it?).

I am admittedly not very experienced with the mechanical arts so it is a bit difficult to articulate exactly what I'm experiencing.

Thanks for reading and for your patience and guidance!

Ocell

You should run with it connected. You need to calibrate the throttle position sensor so it's giving the correct positions to the ECU.

Here's a thread with quite a bit of discussion about it: https://www.yotatech.com/forums/f116...r-help-219947/

Ocell

Also, while the truck seems like it drives normally with the TPS disconnected, once you get it adjusted and reconnected the truck will be much more responsive, and your fuel consumption should improve as well.

element138

Thanks Ocell, I'm reading the thread now...I hope I can avoid buying a new sensor!

Ocell

I think you'll be able to avoid that. They don't seem to go bad that often, they just need to be adjusted, and they are VERY sensitive while you're adjusting. In/out of spec can be the difference of a couple light taps with a screwdriver handle.

Worst case, RockAuto has one for $55.

element138

very good. I'm taking it in to the shop where they've got the tools to make things right. thanks for the guidance!

p.s. Any idea what those yellow plugs may belong to?

scope103

Are those diagnostic connectors? http://www.4crawler.com/4x4/CheapTri...CheckConnector