I also notice that when the truck sits overnight, and you start it, the problem doesn't start happening till 1-2 minutes later. So until it warms up a bit.

 

jondakotaguy,

I just purchased an 04 quad cab 4x4 sxt with the 3.7 motor and didn't notice it when I test drove it, but after driving it back and forth to work my truck is doing the exact same thing??? I came on this site to ask basically the same question. When I am at a dead stop on flat ground and let off of the brake the truck just hops or lopes forward on it's own until I give it gas and then all is fine. I also noticed it does the same in reverse. I cannot for the life of me figure it out and have never had a vehicle do this. Everything else seems to check fine and it runs fine, but it drives me nuts when I'm behind a car and let off the brake to take off and instead of it either sitting still or slowly but smoothly start moving forward, my truck just hops forward on its own until I hit the gas. Very wierd indeed.

 

no i am asking you since this problem has occurred have you ever gone and had the codes scanned and then deleted? even though the light went off doesn't mean you don't have stored codes on your pcm anymore. i have actually seen a post 96 car even with the battery disconnected for a period of time that still had stored codes.

 

Yes I actually bought this truck and got the Dealership if you call it that was supposed to fix it.. but after it sitting total time for about 9 days in their hands no fix.. and they refuse to do anything else to it.. after they spent 1k on it.. and all i see different is 4 new tires and a break job. ROFL

But yes.. I have pulled codes.. and the only stored code is that one misfire.. which has long since been gone..

 

Right I presume an Automatic?

See when you take your foot off the break it should creep.. along.. but this loping, shuttering.. bucking what ever you want to call it is no where near normal and seems to be a standard problem seen alot.

So this is the basic things to go through..
1. First thing.. pull codes.. see whats stored and going on..
2. Complete tune up first.. plugs, wires you name it..
3. Change all fluids including your trans and filter... adjust your bands.. and if you cant take it to the dealer let them fool with it.. (be sure to change your transfer case)
4. Rear and Front Dif. Ive seen a few places that they said they had 'something simular' (Not exact same problem but close) and this resolved.
5. Check the ohm or output voltages of TPS sensor,.. make sure your IAC is working... and so on..
(Ive done more than this.. but this is the primary basic consisious of what needs to be done/checked
6. Probably should be at the top of the list.. but at some point check vacuum leaks.. this might lead to the seals on the intake manifold leaking..

From here.. well I suppose my next thing to do is

7. Replace the Belly pan gasket on the intake man.. along with the rest of those seals.
8. While I'm in there i need to do a valve cover job anyways and will be checking all the springs, rocker arms and push rods and such make sure there are no problems there..

(Also being doing some cleaning work.. polishing and other such... )

9. CAT Ive heard similar problems being fixed by this even though the CAT was not completely gone.. The pressure was actually allowing the pressure to pass but enough was broke down that low level pressure was having more of a time getting out. causing some trouble.

If your gonna spend the $$ spend it right get a high flow cat.. for a little more pep and such.

Well this is just a general idea.. but anyways.. I will be working on mine this weekend.. hopefully with a fix. and then we can try and replicate it out until we get a common fix for the problem.

If I cant fix this with out tons more money.. I'm selling this and going and buying a Ford Bronco or another TJ

 

I guess I'll start with the basics. This Mon. the tranny is gettin flushed, front, rear diff. and transfer case fluids changed and plugs. We'll start there and see what happens. Thanks for all the advice. I will also see if there are any codes stored. No codes have shown up on dash since I've owned it.

 

have you tried running higher octain gas ? i would also maybe see if your TPS is reading the right voltage. also even though you cleaned your IAC that could also be bad..

have you replaced you plenum yet for oil ?

 

Dealer looked at mine today. He reset the PCM and I think the comp that runs the tranny? Or is that the PCM. I dunno. He also upgraded firmware in PCM he says, and he thinks it might learn new settings over time. It's bull**** I know and didn't fix issue

But the truck wad on the scope and didn't detect any codes or faulty sensors. Everything checked out 100%

Still doing it tho

 

also check and see if your cat is clogged ? i would take out the o2 sensors before that cat and see how it runs . maybe bad o2 making run too lean or rich .

 

Yeah.. I was thinking the cat.. maybe a slight clogged issue or something.. not enough to really affect things over all but maybee enough at low pressure to cause trouble.. IDK.. but I know my issue can feel it in park as well.. like a miss/timing issue even though all is shown to be good by mech.

My brother had a 01 1500 he claims he had the same sort of peoblem and it was the solenoid in the tyranny.. ?? Is this even plausible.