TPS Throttle Position Sensor Question
 

Not sure if I explain this right but here it goes. Got a 93 D250 5.9 12v. Have a KN and new 4 " pipe with free flow muffler and the rest stock for the moment.

Today my diesel mechanic made an adjustment on the TPS. From .45 up to .90. I was having overdrive shift problems from OD to 3d and back and forth. We looked at earlier posts etc. We also did the voltage check and did what we did above.

When first driving with the change...it "appeared" to be ok until I entered the freeway and a big rig was right on my tail so I hit it and again...it dropped back into 3d and stayed there and of course...55 mph allowed me to drive on the shoulder of I-70 while the JB Hunter finally moved over. NOT a good feeling experience.

SO ... does anyone know what I can share with him in the morning when we attempt to make another "adjustment". Is there a a "factory setting" or a way of determining what is the "best setting" ? We did the cable adjustments and that helped in the beginning and then the problem returned.

I will be towing some heavy loads too. Just trying to get it right before I het the road. Thanks in advance!

richard

well alot of people have the same problem here when you punch it and your truck shifts out of over drive i havent ever heard about adjusting the throtle positiong sensor before butt i went to dnr customs.com and the have a tps delete kit for like 20 or 30 bucks you just take the entire black piece off of the top of your pump and plug the three wires into the harness and it has a dial you put inside the cab that allows you to adjust the point where your truck shifts into overdrive and it keeps it held in over drive it was well worth the money i spent on it and then some butt good luck to ya man:tu:

i am having the same problem! i looked at that website with the delete kit and i am going to get one but how does it work and does it work right... also is it hard to hook up

Just buy a potentiometer and parts. Itll be even less then 30 bucks! This info is great too:http://www.dieseltruckresource.com/d...&highlight=POT

From what I read it looks like you adjusted your TPS but I'll put this up anyway.

https://www.dieselbombers.com/1st-ge...ensor-tps.html

I have seen were going WOT will hit the TPS and knock it out of calibration. Use the thread above to doublc check your mech's adjustment. Also check its function. If it does not spec out, as said above, the pot kit is a good solution.

The Fix >> http://www.dnrcustoms.com/zen2/index...products_id=97

ya it adjusts it butt also it helps it shift into od i talked to the guy and instalation is simple all you do is inplug the plug from your tps and hook up both of the harnesses

Ok does the kit allow you to pick when it shifts into od?

yup you spin the knob to where you like it

What do I ajust it while I'm driving?

From my understanding you find t he "sweet spot " the speedthat you want it to shit in OD with a dial in your cab that come with the kit. you turn the knob and it chages the votage as THE tps does when you press the fuel pedal...so you play with it until you like where ok kicks in...


Somebody correct me if i am wrong

Thank you for the help! Someone said that it has something to do with me speedometer or something because is bounces around

Your speedo is off a cable, its mechanical and as far as I know has nothing to do with shift points. I could be wrong though, I know the 727's better then the 518's.

Well someone stole my cable mine just has wires plugged in to a sensor LOL

If your speedo is erratic and also affecting your od its probably the vss I have the same problem.

What is a vss?

Is the speedo on teh 518 electronic? I thought they all were Mech... learn something everyday...

I agree. It's probably the VSS. It affects the speedometer, OD,andSpeed control. I am on My fourth one on my 91.5. Of course it is pushing 400,000 mi Hard.

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:argh:Sorry- I should have read all the way through before I sent a message. Vss is the electric speed sensor located on the tranny drivers side. cost is about 35 bucks.

Not trying to sound stupid but with the kit from DNR customs do u have to ajust it when u want it to go in to overdrive at 45 and reajust it for 70 or is it set it and forget it. Just trying to find out how it all works Thanks

i put that over drive kit in my truck about 2 weeks ago and when i got done installing it i went down the road and messed with it intill it kicked in where i wanted it works wonderfull very happy:tu:

Im all for trying this, i am going to order one tmorrow. I looked a TPS on Autozone and the dang thing is $269. And from what the site that sells what you bought describes it sounds liek all the symptoms that I want to get rid of for 39 bucks.

93 tps
 

I have been fighting this crazy TPS for 15 years Finally installed on of the DNR kits. Still had the problem. Hooked up a toggle switch but it is a pain in the butt to remember. I fixed my problem with a scotch-lock on the two wires going to the water temperature sensor behind the fuel filter. That thing was bad/erratic and no longer available. Can't figure out why Dodge thought it necessary on a Diesel and not on gas engines. Works beautiful now. Truck has 390,000 miles and going strong.

Just put a potentiometer to delete the tps it works did it to mine no problems since

The potentiometer works better than the TPS, but i didn't fix mine. Bypassing the temp sensor did. Now the pot can do its work and does. Makes one wonder about Dodge engineers. They could have eliminated both the TPS and temp sensor and prevented lots of headaches.

The first gen wiring wasn't very well thought about but all the fixes are easy

Never had a problem after I installed the potentiometer.

what controls the shifts from 1st to second and second to third?

Valvebody within the trans. It is however influenced by the Throttle-Valve (TV) cable adjustment at the rear of the throttle-cable/bell-crank assembly. :pca1: