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So it's been this way for a while, but recently seems to have become more noticable. I live off the freeway, so in the morning on my way to work, I am accelerating up the freeway on ramp, usually mildly, and it's like I hit dead spots in acceleration,  adding more go pedal will accelerate, but unless I romp into it more aggressively,  I'll hit those dead spots until I'm up to speed. Now I notice it even If the truck is warm and on flat ground from light to light. 

 

Other thing that may go with it ...

If I'm driving say 55-60 in fifth around 2k rpm and going slightly downhill,  I'll use the motor to slow me down, but I keep slight pressure on the pedal to keep at a steady speed(so that I'm not slowing down to much.) When it's in that between state I guess I'll call it, where its coasting or adding fuel, it's like it can't decide what to do, you can hear the motor start adding fuel and then not quickly alternating back and forth( it doesn't cause extreme bucking or anything like that, maybe slight, rpms don't change, its just doesn't sound right to me. My dad's truck doesn't do that, really no vehicle I've driven has. 

 

-My ac noise is .03.

-I've done a re-calibration before, it may have temporarily helped. 

-No codes thrown

-the truck has surged a few times very intermittently when cruise is set, it seems to do it when the ac is on?

 

I'm not super techy when it comes to electrical things either, I have a volt meter, but that doesn't mean I know how to use it lol

Any help is greatly appreciated. 

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if it is anything like a throttle position sensor on must cars I use a lab scope that has its screen on the computer can be had for as low as $60 HANTEK and it will save a buffer of what you are doing. and what you are doing is moving the throttle from nothing to full throttle slowly and steady up and down and watching that there is just a smooth curve of  movement and no quick falling of the graph in any spots of the curve.

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Ok. I'll give that a shot and list the results. If they don't have one or won't let me drive off the lot with it, how much does it cost to buy one?

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Will this work to monitor the throttle?   http://www.obdlink.com/lxbt/

 

None of the auto parts stores will let me borrow it out of the parking lot, and others don't have it. So I have to buy  one, I just want to make sure it is the right one

 

Side note, 75 degrees today, when I drove the truck I didn't notice the dead spots, but it was cold this morning and was acting up pretty bad.

Why would the cold affect this?

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I ordered the obd kx. Should be here tomorrow but maybe out of town a few days. Did a ac noise check w/o warm engine and everything turned on(radio, ac, no grids tho too warm) was between .045 and .05.  I'm curious to see if it will read higher when the grids do kick on. If it does, depending on how much, I'm curious if that will eventually start messing with things. Just a side thought though.

 

I'm hoping to do the @W-T wire upgrades within the month. First is figuring out the go pedal issues 

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AC noise can impact the throttle signal. Like on my truck with a manual it creates a surgy cruise control or using normal throttle it feels like you not holding your foot still even though the TPS signal says otherwise. This is because the AC noise muddy the tach signal from the engine and ECM starts changing fueling commands because of the noise in the tach signal. 

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16 minutes ago, Alexio Auditore said:

Ok so I got the obd link today, i have no idea where to monitor the apps sensor readings. 

 

Plug in the OBDLink. Install the OBDLink App on your phone.  Pair the bluetooth or hook up on the WiFi. Now monitor the TPS signal as you drive on your cellphone. Pretty simple. 

 

Hence why I've got the gooseneck in my truck.

https://mopar1973man.com/garage/modification/279-mobile-phone-gooseneck/#

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I got that part figured out, but I'm not seeing acceleration monitor or percentage. 

I see the log part, says accel x and accel z. Is that it? Kinda laggy tbh when it's monitoring

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I do not think it matters if it lags behind what you want to see nice round curves as you accelerate and deaccelerate and you do not want to see any sudden fall or rises clitches in the graph. I did this with a picoscope on  my toyota the flat top is where I held the throttle wide open. I was able to do this without the motor running by back probing the tps with the ignition on. 

tps.png

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You'll see the same thing numerically. You'll watch the TPS signal and slowly squeeze the throttle and watch the percentage of TPS from 0 to 100 percent. Watching for sudden changes or jump in the signal. 

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Posted (edited)

Ok. I still haven't found it then.

What I mean is the app doesn't have a tps section. It has a log portion where you can watch your speed, mass air flow rate, and then you can add a acell y and z. 

Unless I'm totally missing it, I haven't seen anything labeled tps. ( this is all through the app on android by the way)

 

That being said, I used this accel x and z, it does almost drop or flatten out when i hit those dead spots i talked about earlier.

 

Where is the tps monitoring part on the app?

 

I hope I'm not coming off rude, I'm just a bit lost with this thing, should be simple, maybe it is, I'm just slow:think:

 

Oh wait! Is it absolute throttle position in the logs section? Bingo I may have found it!

Edited by Alexio Auditore

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