Just picked up a blown up 94 2.3 2wd ranger and replaced the head it is running good no leaks smooth idle most of the time.

I have a high idle that I can bring down with just lugging the engine down a bit and it will stay there until I rev it again, another issue is there is a small vary small hesitation right off of closed throttle. I don’t really care about the second issue I am just trying to give a complete picture

Ive replaced IAC and tried to reset throttle screw to the proper position I can tell some one had cranked it up, after that I wasn’t able to get it back to it’s in stock position until I cleaned the throttle body.

If I unplug the IAC, the idle will drop down to about 500. Checked TPS Voltage and it’s a little over 1 volt no mater how far I back out the idle screw. I checked my 5 volt reference and it’s more like 6 volts at least on my temp sender for the pcm. No check egn light any ideas where to go next? I’m more of a OBD2 kind of guy I feel blind without my scanner. I can smoke the intake but everything has new gaskets from the head job.

Ive noticed that the intake might be off of a different year, as there is an intake air temp sensor in the manifold, but no connector to be found and there is an air temp sensor in the air box that’s plugged in.

Please help I've been working on cars for 10 years (I know I’m just a baby still) and feel like it’s my first day.

 

Welcome to the forum

Good info and testing

The 500rpm(barely running) idle with IAC unplugged means no vacuum leak

What about the PCV valve?
Its a variable vacuum leak, if valve is sticking then RPMs will go higher at idle, PCV valve closes at idle, high vacuum, then opens as vacuum drops, if its sticking a bit then high idle

Just guessing, you have covered most bases

 

tank you for the reply i have not tried a pcv and that sound like it might work haven't thought of it but i will try and report back

 

K I think I figured it out. I changed out the PCV the old one was raddled fine but looked like ****, 2 bucks just changed it. No change really but in the middle of summer I’d did not notice the heater was not working... the ecu temp sensor was not getting any flow past it my heater core was plugged bad

flushed every thing and I have good flow and now idle is good it stays at 1100 wile coasting over 15mph then drops down to about 700 under 15mph I swapped out coolant sender and sensor the sender would not move much before. But there was the slight hesitation coming off closed throttle is gone now

I noticed that before repairs, in the morning truck would run fine but got worse as it got hotter.

shes gonna be taking a dirt bike out to the desert today hope she’s all good

Hope this helps some one out there