Cheers everyone,

I am still trying to track down why my car sometimes is running rough and I think it has something to do with the fuel pressure (getting P0300 codes sometimes, too).
The symptoms are: when idling, it occasionally and suddenly starts running rough and short term fuel trims are getting up, when I let off the brake (while in "D") the car will go forward but bouncy. When I hit the brake for a very short moment (less than a second) and let it go again also a short moment it will stop bouncing and idles fine.
So I think the fuel pressure is fluctuating, maybe the fuel pump connection is bad / corroded or something.
I want to test fuel pressure now, but from the workshop manual there is no valve on the fuel rail of the 5.7 HEMI. So what would be the best way to measure it?

Thanks a lot!

 

Does the PCM monitor fuel pressure???

 

Make sure your brake booster doesn't have an internal vacuum leak, causing it to lean out when pressed.

 

No, can't see any value on the OBD and the Diablosport.

But I found a different thread:
https://dodgeforum.com/forum/3rd-gen...-location.html

I think I will have to look closer...

 

Ordered a pressure testure but hasn't arrived yet.
Today I removed the fuel pump connector, cleaned it all out, but no difference. Contacts also hat no signs of any corrosion.
So will check fuel pressure and go from there.

 

You can rent the tool from auto parts stores. Free of charge when you return it. It's a tool you'll rarely ever touch.

 

We don't have these Auto Parts stores over here in Germany though. And there are no places to rent tools like that unfortunately. Maybe I should open up a shop for this stuff

 

Sorry, should have checked your location. Yeah, here they rent you the tool in the hopes of selling you parts.

 

The idea ain't too bad to be honest. Customer has a problem, comes to your store, rents a tool and buys the parts, does the repair, messes it up on its own and needs more parts

 

Exactly! And they charge you full price for the tool up front, just in case you feel like keeping it. They issue full credit when you bring it back. I can't tell you how many tools I have that I've only used once, so I go that route when I can.