[tmccorkel]

Here's a brief tutorial on my method of adjusting the TPS (throttle position sensor) on a Kia Forte.

Step 1: Gather your tools
A. Multimeter (set to DC voltage- 20 scale)
B. A pin or needle (mine have alligator clips attached to them)
C. A small phillips screwdriver

Step 2: With the engine off, locate and remove the connector from the top of the TPS sensor (attached to the left side of the throttle pedal)

Step 3: Insert pin or needle into the third wire from the left (orange). When inserting, make sure that you stick the needle where the wire comes into the connector (the side with the yellow retainer)- not the side that plugs into the TPS sensor. This is called back-probing.

Step 4: Plug the connector back into the TPS and connect the multimeter (positive to needle on TPS plug and negative to a good ground).

Step 5: Start the engine. Your multimeter should read ~ 0.78 volts (that's what mine was). If your multimeter is reading 0 volts, check your connections- you may not have a good connection with the wire inside the connector.

Step 6: Loosen the 5 screws circled in red, but don't remove the sensor ( I borrowed this pic from the original tutorial).

Step 7: While watching the multimeter, rotate the TPS until you read ~ 1.0 volts. Mine started out at 0.98 volts, but decreased to 0.94 volts as I re-tightened the screws. It may also take some wiggling/ more loosening of the screws to get the voltage to change.

Step 8: Re-tighten the 5 TPS screws, holding the sensor in its new position as you tighten (voltage will drop some).

Step 9: Remove the needle from the connector.

Step 10: Put your tools away! It's time to enjoy your work!

 

[Robertisin]

Thanks for the DIY voltage measurement. I got a reading of 1.02. Not bad as I did it a few weeks ago with not measuring.

 

[ForteGT2]

Super job on the DIY^^^

Remember, you don't want 1.0 volts! 0.94 volts means you will have no "dead spot" -- 1.0 volts is where the engine begins to respond to the throttle input.

tmccorkel you might want to start a new post with your DIY so more people see it -- as this thread grows it will be lost in so many pages...

 

[tmccorkel]

Thanks for the compliments and input. I made some slight changes to the tutorial, regarding voltage specs. and created a new thread in the DIY section.

Here's the link: http://www.forteforums.com/forums/d...com/forums/do-yourself-articles/3163-tps-adjustment-procedure-throttle-mod.html

If anyone has better pictures, or ideas to make this easier to understand, don't hesitate to let me know.

 

[Robertisin]

Great DYI!!! I guess I will have to re-adjust it to read under 1v.

 

[Koupster # GP]

Had this mod done on my Koupster by the service technician, when my car went in for it's 15k service......what an impact, it drives like i installed a chip on it..it was intially sitting on 0.7

 

[Robertisin]

Reading is now at .98v Works great!

 

[computerdoc01]

Best Kia Forte Mod

I just completed the mod. What a difference! Like a new car! I did not monitor the voltage. I put in in my garage, chocked the wheels, and let it idle. When I turned the module forward I monitored the rpm's. As soon as the rpm's started going high I backed off until idle was normal. No lag or hesitation. The car is now fun to drive. Thanks for the info.

 

[tanman]

hey computerdoc, what is your car idlling at now that you have done this mod?

 

[Lechner]

Before i did this my rpm would start at about 1.5 and now its at about 2 when idle. Is this a problem?

 

[tmccorkel]

Your TPS is probably set over 1.0 volts.

 

[Lechner]

Your TPS is probably set over 1.0 volts.

how do i fix it? and can i drive while it is like this?

 

[ForteGT2]

how do i fix it? and can i drive while it is like this?

Loosen the screws and move the switch -- adjust aft at least 1/16" (top toward the rear of the car). If you just loosened the screws and moved the switch to the full forward position the accelerator pedal switch is telling the engine the throttle is open -- your engine is trying to respond as if your throttle is open. That's why it's important NOT to have 1.0 - or higher - volts present. You can drive it that way but your idle will be erratic...best to fix it ASAP!

 

[Lechner]

Loosen the screws and move the switch -- adjust aft at least 1/16" (top toward the rear of the car). If you just loosened the screws and moved the switch to the full forward position the accelerator pedal switch is telling the engine the throttle is open -- your engine is trying to respond as if your throttle is open. That's why it's important NOT to have 1.0 - or higher - volts present. You can drive it that way but your idle will be erratic...best to fix it ASAP!

Alright thanks its too late at night to do it now and i have to drive to schools tomorrow so i will have to wait untill tomorrow afternoon

 

[P-51]

What am I doing wrong? I've got the screws loose, but it won't move?

 

[P-51]

Nevermind, I got it. I had to completely remove the top screw. Not sure why.

Car drives better, no doubt. But I still think the throttle sensor needs to be recurved. Needs more sensitivity in the low end.

 

[ForteGT2]

Nevermind, I got it. I had to completely remove the top screw. Not sure why.

Car drives better, no doubt. But I still think the throttle sensor needs to be recurved. Needs more sensitivity in the low end.

I had to remove the top right screw too...I believe it is a set (locking) screw -- the other four are adjustment screws and the top right locks the switch in place to prevent movement if the others come loose.

 

[P-51]

Yeah, it was weird, I wondered if it would screw back in. Like maybe they adjust it on a jig, shoot the 4 screws, and then the 5th screw self-taps a new hole in the base to lock it down. But, no problem. Weird.

Now I wonder why they set the car up with the dead zone, and if there might be any long-term effects of this mod. Like, say something in the assembly wears over time, maybe the deadband was needed. I've got it adjusted to 0.97V, maybe it will wear and go over 1V causing problems? Who knows.

 

[ForteGT2]

Yeah, it was weird, I wondered if it would screw back in. Like maybe they adjust it on a jig, shoot the 4 screws, and then the 5th screw self-taps a new hole in the base to lock it down. But, no problem. Weird.

Now I wonder why they set the car up with the dead zone, and if there might be any long-term effects of this mod. Like, say something in the assembly wears over time, maybe the deadband was needed. I've got it adjusted to 0.97V, maybe it will wear and go over 1V causing problems? Who knows.

If you can...check the voltage for a couple of weeks to get an idea if wear or temperature affects the voltage. If after a number of weeks everything stays the same then one can assume it will stay that way until it is adjusted again.

It is strange that they built it with such a dead zone... Possibly just keeping it as safe as possible?

 

[CorsaKoup]

Made this adjustment last night. OMG what a difference. I adjusted it all the way forward at first, but the car idled high, so I backed it off a couple of mm and it's perfect now. Absolutely no freeplay in the throttle, which feels kinda wierd, but my launches are smooth now. Thanks for the tutorial! I may actually enjoy driving this car now.