98 Ranger Help

[onlyme]

I been searching the internet for an answer, but still a bit complexed. My 98 Ranger 2.5 has an issue, P0122, high idle, no other codes thrown. I bought this truck with this issue, I did however put a new TPS sensor on the truck, but the idle remains the same. I did test the TPS sensor and connector with a multimeter to make sure it was receiving voltage and ground, and I did the TPS sweep test with the throttle also. There was no spikes or dead spots, and the idle was about .96-.97 volts to 4.5 volts wide open.

I know however that the throttle plate screw was messed with, which I am not sure how to reset correctly. I believe that may be what's causing the issue, I know the truck is suppose to idle at like 750 rpm, but unfortunately my truck does not have a tachometer to read the rpm. Right now when it starts it idles so high it sounds like your cruising down the freeway when in neutral (it's a manual)

Is there a correct way to rest the throttle plate screw to the factory setting?

 

[tomw]

You travel the web... On the other site, I recommended turning the screw CCW. With the engine warmed up, just turn the screw. If you turn it too far, the engine might stall, but you can change it, and re-start the engine. It is not rocket surgery or brain science.
You might consider checking the IAC for cleanliness and operation. It should give a fast cold idle speed, and control idle when the A/C is engaged, or the transmission placed in D or R. If the idle stays high, it could be gummy.
tom

 

[enjr44]

I would disconnect the IAC and set the idle using the adjustment screw to just above stalling. The main reason the screw is there is to prevent the butterfly from hitting the sides of the throttle valve.

 

[holyford86]

There are adjustment procedures for setting tps baseline, if you dont have a tach you will need to gain access to a scan tool that shows live data to accomplish this.

Sent from my SM-G900P using Tapatalk

 

[onlyme]

I don't have a tachometer but I do have a scan tool and multimeter, so I removed the IAC even though it is almost new and cleaned it, and set the TPS voltage to .98 at idle and that seemed to fix the problem and clear the code.