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Discussion Starter · #1 ·
Dead pedal.... ugh. I have been battling this for a couple months now. Any insight would be greatly appreciated

I have a 98.5 24valve power train and chassis stuffed below a 1958 chev Viking 2.5 ton cab. I'm running dakota digital gauges and all the stock wiring harness is still in the chassis with the exception of the gauges.



Couple months back I noticed intermittent dead pedal and irratic throttle response. I had been having issues with a set of 150hp Injectors and hard starting so I thought it was that. I put the stock injectors back in and my hard starting went away but not the dead pedal



I have since replaced the map sensor and put in a apps sensor. Disconnect my edge comp box.. I did notice the alternator wasn't charging so I just replaced that and had both batteries bench test. I should mention the batteries are located in a underhung box under the deck... I just relocated the temp sensor as that hadn't been done yet

I also just ran it today with the alternator charge and field wires disconnect think maybe its ac noise but that didn't help

I would love to get my summer ride back on the road. Thanks
 

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Probably dirty, even slightly calcified, terminals/cable ends or high resistance in long cables.
 

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Pull codes with a scan tool, not key, and does wait to start light come on everytime immediately when you turn the key to ON? Any other engine drivability issues other than dead pedal, ofthe when fully warmed up after an hour or so, or dies it do it cold?
 

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Discussion Starter · #4 ·
Thanks for your response i have P0122 throttle position sensor circuit 1 low.and po237. Turbo boost pressure sensor low





I did do a boost pressure test and found a leak and repair it and now its holding pressure

The dead pedal now happens as soon as I start up the truck. I can't drive it anywhere.... the battery cables are very long as the go all the way back to the undermount box drivers side under the deck...
 

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Did you do an APPS reset after new apps. Those codes can be dueto the cables and alt issues. What is charging voltage now? That is along ways away for batteries, Cool truck, when are you going to paint it, what color?
 

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Discussion Starter · #6 ·
I have been doing apps reset every time the batteries are disconnected. I upgraded to the timbo apps when the sensor was changed. it's only charging at 13.5 volts. That's with the grid heaters disconnected. Havnt run it longer than 10min as I can't get it further from the house with the dead pedal... the longer battery cables are 4/0 welding cable from the Battery to the starter and starter to tipm. Alternator to tipm. Checked grounds and all have continuity back to the battery.



No paint. Leaving the the patina.
 

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I have been doing apps reset every time the batteries are disconnected. I upgraded to the timbo apps when the sensor was changed. it's only charging at 13.5 volts. That's with the grid heaters disconnected. Havnt run it longer than 10min as I can't get it further from the house with the dead pedal... the longer battery cables are 4/0 welding cable from the Battery to the starter and starter to tipm. Alternator to tipm. Checked grounds and all have continuity back to the battery.



No paint. Leaving the the patina.
Sounds like TPS is still having issues.
 

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This does not sound like normal "Dead Pedal" issues for a Dodge Cummins. 13.5 is low, Should be 14v. Is PCM OK? Probe pin #3 on apps and see what the voltage is and is it smooth from idle to WOT. It should be .64 at idle with a Timbo and smoothly graduate to about 3.8v. Check wire between APPS and ECM.

PS I consider Timbo Junk especially on 98.5 and 99. You truck is supposed to have an idle voltage of under .529v. Most APPS are adjsutable to that range of .48 to.53. The Timbo is not adjustable and can only put out .64v for idle. This confuses the ECM into thinking you are accelerating when you are not and causing surging. The voltage your apps is supposed to be is printed on the old APPS or ECM. Reset does not work if over that range to .529v.
But I do not think that is your issue presently because it does not prevent acceleration above that.

I think if ECM i good WTS light working as it should, the VP is all done. Check out Bluechip diagnostics.
 
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