01-04-2018, 04:48 PM
Join Date: Jan 2018
2004 Hemi idle / stalling issue
I swapped an entire Hemi drivetrain from a 2004 Ram into my 2004 Ram (which originally came with a 3.7 V6).
Everything is working but the idle quality is poor and the engine stalls within a few minutes.
I had completely disassembled the engine, cleaned, inspected and measured everything and all that was good.
Stock tune, no modifications, no check engine light.
The engine sounds smooth - no ticking or knocking, etc.
Neither of the trucks had the SKIS (Sentry key system) so that shouldn't be an issue.
Attached are a few screenshots from logging with vcm scanner.
The MAP value seems to move around a lot, as do the timing and rpm.
I'm not sure how steady these values should be.
I noticed the short term fuel trim gets to almost -30% before the engine stalls.
It definitely smells rich also for the first minute or two.
I hooked up a fuel pressure gauge - it reads 58 with key on, engine off, and bounces back and forth between 60 and 64 with engine idling.
Does anyone have a log of a similar vehicle on cold startup so I can see what these charts should look like?
How steady should the fuel pressure be when idling?
I'm thinking I have a bad MAP sensor or a bad fuel pressure regulator.
Any advice is appreciated.