After an engine swap it stalls when driving

Hi,

I checked the fuel pressure specs for both engines and they are the same. See pics 1 and 2

When it stalls, is it like the key is turned off or does it seem more like it's running out of fuel? Have you checked fuel pressure?

Let me know if you have checked for codes. Also, if you have a live data scanner, let me know what the short-term fuel trims are.

Here is a link you may find helpful for testing fuel pressure:

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Let me know as much as you can.

Take care,

Joe

See pics below.

Hi Joe, thanks. Someone told me to also check the EGR valve or the Idle control valve when I called to price out the EGR valve for my truck. They said Dodge doesn't make an EGR valve for that year. I know I need to replace the downstream o2 sensor. I replaced the upstream o2 sensor and does the 5.9 have a different Ignition switch than the 5.2 motor? Right now, I'm doing the elimination process.

Hi,

This is a gas engine and not a diesel (Cummins), correct? Just asking because there is a 5.9L in both. LOL

As far as the ignition switch is concerned, they are the same.

When this happens, explain what you experience. Is it like the key is turned off or like it is slowly running out of gas?

Also, the IAC is for idle speed and won't cause it to stall if your foot is on the throttle driving. As far as the EGR, I need to confirm it is a gas engine. Also, let me know if it is a 1/2 ton or 3/4 ton.

Joe

See pics below.

It is a 1/2 ton and gas when I first turn the truck on the RPMs go really high then drop fast the truck sounds like it wants to shut off at idle rest. When I'm able to drive the truck, the engine just shuts off in gear. If I try to turn the key, it just cranks no start.

I had AutoZone tell me to test the fuel pressure it also has a new fuel pump.

Okay. I wanted to make sure I had the right engine. As far as fuel pressure, it would hurt to test. I have a question. First, the idle issue could be related to the idle air control valve. However, it shouldn't prevent it from starting if you feather the throttle open a bit.

When it stalls and doesn't restart, have you checked to see if it lost spark or fuel? I ask because if it takes a while until it restarts, it could be a few different things.

If that is the case, when it won't restart, see if it starts for a couple of seconds using starting fluid. If it does, then we know we have a fuel-related issue. If it doesn't make a difference, check to see if there is spark to the plugs. Here is a link to help:

https://www.2carpros.com/articles/how-to-test-an-ignition-system

As far as testing the fuel pressure, I attached a link above explains how it is done.

Let me know what you find.

Joe