Engine stutter, low rpm, WOT
Thread Starter
Teching In
Joined: Jun 2013
Posts: 7
Likes: 0
Engine stutter, low rpm, WOT Trying to diagnose what could be the cause, here is a log file and I experienced this issue around 5:45, 7:45 and 9:00. No other issues noticed throughout the rpm range. Running speed density tune with no DTC associated with this issue.
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
I'm a total novice at looking at other people's log files, but I have never seen such crazy swings in Ignition Advance. With a little throttle you have 56* of advance. Then at WOT you sometimes haves 20* of advance, but at other times only 3* of advance.
You did not log anything related to AFR nor Knock Retard.
(I know that what I see you your log file depends upon what I have in my CFG file.)
Any chance you can upload the Tune file too?
Your log .cfg file will help us see the same thing as you.
Perhaps one of the experts here (not me) will be able to help you out.
You did not log anything related to AFR nor Knock Retard.
(I know that what I see you your log file depends upon what I have in my CFG file.)
Any chance you can upload the Tune file too?
Your log .cfg file will help us see the same thing as you.
Perhaps one of the experts here (not me) will be able to help you out.
Thread Starter
Teching In
Joined: Jun 2013
Posts: 7
Likes: 0
Motor is a stock 2001 5.3. Manual tranny with shorty headers. KR was pretty much non-existent. I think the issue may be the fuel pump (Stock Jeep TJ). Here is what I believe the current loaded tune is, I haven't changed it in about a year and still running SD until I get a WB to tune the MAF. As far as AFR, don't have a WB to datalog that. KR can be viewed on histogram #2. The config file I used was the standard one.
Stock Jeep TJ pump is supposedly able to support the motor, have good pressure at rail at idle. Running it returnless with a corvette style regulator/filter setup.
Stock Jeep TJ pump is supposedly able to support the motor, have good pressure at rail at idle. Running it returnless with a corvette style regulator/filter setup.
Last edited by XDR; May 11, 2015 at 10:53 AM.
