Dead pedal with no codes

[Christolher]

Hey guys ive had dead pedal ever seens ive put new II hotrod pump on and timbo tps. I think it maybe in the tps because when i put the first one on the lowest i could get it to set was .750 and he sent me another one that he checked before he sent it and said it read .680. I put it on and with my cheap habor freight meter and it said .710. So i adjusted it till it went up and then backed it up till it was at .71 then back it off a half turn then called him and he said to take it up till it went up then back it off a half turn. So i check it before i mess with it again and it was at .750, I went to adjust it and could not get it below .720 so i set it at that. 

 

I know the instruction says .580-.700. Has any of u had this problem? 

 

If so i could get him to get me one that is lower and try it.

 

And im checking codes with a smarty the only codes it will show is P0230 an PO1693 and sometimes a PO500 which im not spinning the tires and dont understand why it throws the 500. I dont have ground hooked up to fass so that probably is the reason for the 230.

[dripley]

I have put the Timbo apps on my truck 3 or four times and never once used a volt meter on it. Crank the truck turn the screw until the idle ramps up then back it off a quarter turn or so. 

 

The dead pedal I have dealt with in the past was wiring or fuel pressure related. Even surging throttle I went thru was not the apps but a bad 5v signal wire.

[Christolher]

Well the quad show tps is working and Im not sure where to start?

 

I got redline hooked up to harness from injection pump that i need to unhook, pump isnt tapped and box is turned off but SO pump didnt have a problem with the box before. 

 

If i cant figure it out soon im going have to let someone look at it and it seems to do it more when the engine is hot and seems like when its colder outside.

[dripley]

Lets be sure we are on the same page. Is your pedal completely dead as in not working at all? The dead pedal I experienced was a random drop to idle while driving down the highway with no throttle response. The throttle would come back after a short span or an engine restart. 

[Christolher]

Yes when your driving it goes to idle and is getting worse. It has had a problem slow starting a time or two also seen this has happened.

[dripley]

How is your fuel pressure?

[Christolher]

I got good fuel pressure at 15 lbs with a  FASS

[dripley]

I just lost my VP after 270k. The first sign it gave was hard starts. Since you just installed a rebuilt VP it could be you have a leak somewhere in the fuel lines, high pressure or return lines. A small leak in either will let the fuel drain back to the tank and air in. The results are hard starts. That is what I thought was my problem, but was not to be. It would be a good idea to look all of those connections and see if any are wet. Follow the return line from the VP back to behind the fuel filter canister and you will see a tee. The other line goes up to the back of the head. You need a mirror to see that one. That one seems to get over looked. Maybe this will help with one problem anyway. 

 

As far as the 222 code. The cheap tps I bought on ebay did the same thing. Clear the code and bam right back at engine start. Truck ran fine though. I despise electrical gremlins.

[Dieselfuture]

At idle ecm is in full control unless you over adjust the tps which sounds like you got 1/4 to 1/2 turn backed off, it should be fine. Do you have a way to see data coming from tps as you're driving to see what % it is and if it randomly drops a signal?

Engine may idle different then others you see depending mostly on how wore out the injectors are and/or pop pressure. There is a whole thread on this here somewhere. 

Have you done WT mod and went through wiring mostly grounds on your truck, these trucks have lots of gremlin problems with lose wires. Best I to go through it all. They used crimp/glue connections in main wiring harness in multiple places, wt mod takes care of some of them. 

Alternator ac noise is another problem on these trucks that will take out electronics with time if not taken care of. And no you can not use Harborfreight multi meter for testing ac noise, need something more accurate like fluke. 

I don't think it's timbo apps, although I heard of people claiming they had a bad one before. But 2 in the row, idk. Keep checking things and look into what I mentioned if you haven't already. 

[Christolher]

Well i havent did the WT mod and havent heard of that mod. But i would like to try it and the AC noise mod that ive been wanting to do for awhile, I searched for WT mod but cant find anything. Can someone point me in the right direction?

 

I do have a fuel leak on the head i guess a tube isnt sealing ive had that problem before with aftermarket orings that cracked. I never had it to give me dead pedal tho. I was parked on a hill when it didnt want to start right off that maybe what happen then. But i dont have the factory fuel filter base the injection pump and off the head goes to the tank on the return.

 

I sent the first timbo back and had him to check it and he said it checked out at .68 and thought i had a ground  problem, he wants me to try and run a ground from my battier to the tps. i would like to go threw the harness also. i just replaced the harness last year with one i got out of salvage yard that looked good. i had a bad harness before and it had been spliced together was the reason i replaced it.

[dripley]

It is a good bit to read but the mod is fairly simple.

Edited December 26, 2019 by dripley

[Mopar1973Man]

Dead pedal - is when the throttle does nothing period but idle.

 

Limited Pedal - is when the throttle works but limits to a particular road speed or RPM.

 

Now if there is a APPS issues with dead pedal it will ALWAYS set a code. Now a dead pedal without a code is typically the VP44 PSG failing. This is because the ECM commands a value that is out of range and the PSG is protecting from a wide open throttle or below idle fueling which would stall the engine. Limited pedal is typically the ECM being the fueling map is damaged.