Rough and Inconsistent Idle, frequent stalling and bogging down under acceleration

[Wesley Myers]

I have a 2005 Dodge Ram 1500 Hemi that I have been trying to fix for almost two years now. My brother ran it to empty one too many times and clogged up Injectors and the truck wouldn't start properly again. Had my mechanic take it apart to find the cause and found that a valve had broken off. He said that it didn't cause any damage to the cylinder but it did make a minor scratch on the cam (not sure how minor) but said it shouldn't affect drivability, which I now very much suspect isn't the case. After replacing the valve and putting it back together, the rough idle persisted and it would stall when in drive if you were breaking or coming to a stop. We hypothesized that the problem was not the ECU which we replaced, this slightly improved the rough idle but it still stalled. So we had the injectors professionally cleaned by injector RX and again the idle was slightly improved and the stalling is more scarce. However, it will intermittently start idling rough like it has a hot cam and a bad tune, bouncing from almost no idle to normal idle speed. When I took removed the injectors I found a ground strap that wasn't properly bolted down. I tried to run it by pressing the ground strap down with a screwdriver and it still ran rough, I haven't found a proper nut to bolt it down yet, but this doesn't seem to be the underlying issue. I also saw that the belt tensioner was loose and could visibly see it moving as the engine idled. Lastly, it is throwing two codes P0172 and P0175. The only guesses I have left is that it has faulty spark plugs, coils, needs a new camshaft or a combination of those issues.

 

[LoneWolf3574]

P0172 & P0175 mean both you're running rich on both banks, too much fuel.

1. Faulty front heated oxygen sensor, not likely IMO since both banks (sides) are running rich.
2. Faulty fuel injectors, a possibility, however you did say that you had them repaired/refurbished by InjectorRX. I have no idea how good or bad this service is, so...
3. Exhaust gas leaks, I've got nothing on this one
4. Incorrect fuel pressure, the fuel pump is an all in one unit and the fuel pressure regulator may have failed. Check the pressure on your fuel rails, it should be around 60psi if I remember right.
5. Faulty Mass Air Flow (MAF) sensor, it's a cheap sensor and over time they can become fouled and/or fail.
6. Ignition misfiring, when was the last time you changed out spark plugs? How do your plug boots look?

Over time, this condition will ruin your catalytic converters as they work their hardest to burn the unburnt fuel passing through them, giving you an even larger bill down the line.

That's all I've got for now based on the information you've given. Good luck and keep us posted.

https://www.autocodes.com/p0175.html
https://www.autocodes.com/p0172.html

 

[RoadRamblerNJ]

Buy a can of spray cleaner and clean the Mass Airflow Sensor. It may not be "seeing" the actual air flow, causing it to report incorrect data to the BTBT (Big Truck Brain Thingy), which then enriches the fuel/air ratio, causing the stumbling.

 

[RoadRamblerNJ]

In simpler times, we called this a stuck float.