Ok, real quick: 2005 4.7, 2WD, 115k miles -

Most problems I have fixed by hunting in these forums, and are listed chronilogically, however, my final question seemed un-discovered, but I may be missing something.

First problem: truck shutting off in middle of driving
Fix: I replaced the TPS and Crank sensor - RESOLVED

Second problem (month later): Truck dies immediately after you accelerate hard, but can be started when you turn the key OFF and try to start it. Low, easy accelerations do not kill motor. CEL came on, code given was the MAF sensor.
Fix: Replaced MAF, did NOT fix problem, but then I replaced the cam sensor - RESOLVED

Important fix to be noted: Battery replaced (dead)

Third problem (month afterwards - today): Truck decided one morning to not start, starter would turn engine over, but would not fire up. When I gave it a little gas, worked fine, and CEL came on. CEL codes were P0068 and P 0 1 2 3. The truck would drive fine, but the tachometer would bounce quite a bit, sometimes stalling out. The night before our sprinklers were spraying the hood, so I figured the TPS may have shorted. I replaced the TPS (2nd time now) and the starting problem was fixed, HOWEVER, the CEL stayed on, and the tachometer was still bouncing, with the occasional stall/shut off problem - but only at a low RPM - with or w/o the A/C engaged.

Few hours after replacing the TPS, the CEL goes off, but symptoms prevail, and get worse. On "rolling stops" where you then accelerate, the truck feels like the transmission is "slipping" from that 1st/2nd gear, but then immediately corrects itself. Thinking about the stalling (at idle this time) I re-replace the CRANK sensor - to no avail. I checked the tranny fluid, and was 1 qt low, and made sure that was topped off, but still get the "slipping" problem.

My question: I still have the bouncing tach, stalling at low RPM, loss of acceleration (tranny slipping??) and have replaced several sensors. Could this be an EGR problem, even though I have NO EGR CEL code?? OR am I missing something and I have another problem(s) ....I am beginning to feel lost, as well as frustrated.

ANY HELP is greatly appreciated!!! I hope someone has some insight for me or has experienced this w/ a fix!!

 

Ultra:

What is the tune up/service history on this D? The 4.7/5.7 engines call for spark plug replacement every 30K. Not that you would be having this type of issue if the plugs are 10-20K over, but if those are OEM plugs at 115K, time to get them out of there!

How about trans service history? Dodge had an issue on some of their sump filters which would crack and not pull fluid from the pan properly causing stalling.

A bad TPS is usually earmarked by trans shifting issues, and the water on the hood should not have bothered the new one.

There is an IAC or IAB valve on the throttle body next to the TPS that could be dirty or bad.
I would remove and possibly clean or replace it.

While we are at this, how about your coolant and rear axle lube. Coolant should be done every 5 years OR 100K.
The factory spec on rear axle gear oil is 30K, but if you put some good Royal Purple or Mobil 1 synthetic in there you can run it 50K without batting an eye and maybe longer.

Don

 

Don,

Thank you for that info. I often wondered about the plugs, and I should change them anyway. You mention the trans sump problem, and I was actually thinking of doing a service on it (I am not the orig owner, so I may have been abused) to see if it helps any. The times it feels to "lose power" are times on a rolling stop, where the trans should be down-shifting to 1st, but feels like its in 2nd or even 3rd (feels sluggish, but catches up as the RPM's go up). Sometimes when we stop, it has that clunking feeling in the trans, similar to a bad U-joint, but doesn't feel like a u-joint problem.

Since there is no CEL, should I not think its EGR related? I did replace the PCV for the heck of it, and at first, it seemed to be better, but as we drove it, the stall problems just came back.

I will check the plugs, clean/check the IAB/IAC and see if that helps any. Thank you for the info, and if you know my question about the EGR, that would be appreciated.

PS- Previous owner changed rear diff fluid before I purchased w/ Amsoil synth.

 

UPDATE: I did the trans filter/fluid, didn't help. I then cleaned the TB w/spray, getting it into the IAC "slot" as well. I also used SeaFoam foam cleaner for the upper intake mani. I did get a CEL right after cleaning it all, but After doing all of that, my NEW troubles were this:

In PARK/NEUTRAL - car would immediately stall and die
In Drive/Revers - car would idle perfectly, run great, minor shift problems, but idle felt a bit high

I drove it like this for a few days. Last night, while driving it, accelerating out of 2nd gear, car died while driving, threw a CEL, but I was able to put it in N and restart immediately, and the problem never came back. CEL went away today. So today, my fix was this:

Replaced the IAC with new one. So far does not die in P or N, drives fine (I have only driven it 5 miles since new part) however, when I got home, in P, the needle still bounces from 550-1000RPM, not sure if the computer still needs to learn the new IAC, or if I'm still having something else go wrong...I have replaced all sensors, except that one in the "magnum" box right before the TB.

Any more thoughts?

 

Ultra:

I was going to recommend the AutoZone TF98 trans filter/gasket kit for $14. So for it seems to be the best deal on the market for a 45RFE/545RFE fluid and filter change.

Do a battery disconnect reset at this point to take everything back to ground zero. Remove the negative battery terminal, and then depress the brake pedal for a minute or so.This should reset everything and clear out and glitches thus far.

Don

 

What code shows with the CEL?

 

Does the battery disconnect reset bring everything back to factory settings? Including the PCM and TCM? I've been having some problems that may be related, but didn't think you could reset anything that's in the computer's memory by disconnecting the battery. You've piqued my interest...

 

kkpjm:
As far as I know, certain values of data that are recorded while the vehicle runs can be erased by a battery reset.

Others are hard values that are retained regardless of power loss and have to be cleared by computer direction.

It never hurts to perform a reset after replacing a sensor to give the system a fresh look at proper signals.

Don