03 Ram 1500 4.7 studder replaced TPS

[Agkirtley]

Driving today around town and I went to slow down pushed the clutch in and the truck dies. I think nothing major of it come out of the store and try to drive home... Every time I go to stop it dies, even when I'm going down the road with consistent pressure on the pedal it'll randomly act like I have let off the gas then a few seconds later pick back up. I changed out the TPS and cleaned the Idle Valve. Now it'll idle normally but once I touch the gas even in neutral it starts going up and down in RPM. No codes.... Thanks in advance for the help.

 

[Agkirtley]

Well after doing some digging and what not my odometer flashed a high charging voltage code so I changed the alternator because I've read that something wrong voltages can mess with a lot of different things... Still having same issue.

 

[AaronDoesntCare]

Go buy a new camshaft and crankshaft position sensors change them out and see if that fixes the problem. (if not you can always take them back)
Had the same problem with my 05 but it's automatic not standard also seen a couple post for the same symptoms and checked the transmission fluid and noticed it had bubbles in it (because of old gaskets on both transmission filters) causing it not to engage the torque converter. But this was also for a automatic.. hope this helps

 

[Agkirtley]

Well still not running right. I've replaced cam and crank sensor, new plugs. So if I accelerate at full throttle it runs like it should. Anything less than that it hesitates and studders. I have absolutely no idea where to go from here. Any thoughts? Short list, fuel pump, TPS, AICV, alternator, plugs, crank and cam sensor all been replaced. Throttle body completely cleaned no check engine light. Even reset computer.

 

[Agkirtley]

 

[Marley]

Check for vacuum leaks.
And if you wanna throw another inexpensive part at it , map sensor.

 

[Agkirtley]

Well I've checked all the hoses for vacuum leaks and couldn't find any or hear anything. I'll try the map sensor tomorrow.

 

[LoneWolf3574]

I think this may be one of my dense days, I don't quite understand what you're trying to show in the video. Your engine is surging while lightly depressing the throttle? So the following is just guesses but I don't hear any missing in the video, so I think we can rule out your coils, plugs, and injectors. That leaves the throttle or fuel delivery as the cause for your surging and I don't think you have a drive by wire system (electronic throttle and gas pedal) in your truck, please correct me if I'm wrong on that. I suggest checking your fuel pressure, if it is erratic during these surges, either your pump or your fuel pressure regulator is going bad or there may be some sort of obstruction at the suction or in the fuel line (not as likely).

 

[Agkirtley]

Well my fuel pressure was around 38-42 then I changed my fuel pump even though it was only just over a year old. Now my fuel pressure at the rail is 48-50 where it should be. The video was me holding the throttle steady probably around 1500 rpm. When I'm driving at a constant speed the truck acts like I have left off the throttle completely intermittently,Then picks right back up.

 

[LoneWolf3574]

Well, I don't think you don't have a fuel delivery issue then. Your ECM and throttle are all that's really left that I can think of that do not require a lot of work that might cause this. Did you try replacing the MAP sensor as Marley suggested? No change I'm assuming? How about your IAC? You cleaned it, did you replace it?

Have you tried monitoring your sensors with an OBDII dongle? If you have a BlueTooth OBDII scanner and an app like Torque on your smartphone or tablet, you can see things like your EGR, throttle, and IAC positions.

Another possibility to consider, your intake is plastic and your gaskets are a type of rubber, you may have a crack in one of the gaskets or manifold.

 

[Agkirtley]

Well today I spent some time at a friends shop with his scan tool. Ended up that the PCM isn't sending voltage to the air idle valve so that's causing all sorts of issues with it running. Looks like I have to get a new PCM ordered. Thanks everyone for all the help.