-
Jtech Fueling issues
Ive been running a jeep xj built 4.7 stroker for around 1 year now, Its been on Hp since October. Finally desired to correct the fuel trims by locking out closed loop, pulled the O2 and disabled. Reset pcm. Started her up and shes running at 12.80 idle, so I start pulling fuel out via EGR off map..... No mapped how much I pull out shes still sitting at 12.8, min injector pulse has also been lowered, seems she cant go under 5.0 ms no matter what i do, normally closed loop shes at 2.0-2.5ms tops. Am i missing a step here?
-
fuel>general>min pulsewidth ?
-
Min pulse has been changed, currently at 1180 from 1600; zero chance shown at idle.
-
-
1 Attachment(s)
Quote:
Originally Posted by
spoolboy
Post your file.
here it is, thanks for the help
Attachment 102007
-
Is it getting out of the cold/warmup maps?
-
Yes she’s reaching full temp and out of the 120 sec warm up window.
-
Did you try resetting all adaptives?
Lastly, are your coolant temp and map sensor reading correctly? Did you happen to change to a 2 bar sensor or something?
If it's none of that, I am also stumped.
-
I’ve got a redundant coolant temp sensor, they read within 5 degrees of each other, still a oem mopar sensor; and I’ve reset adaptives with scan tool and by pulling battery. That’s also what I was thinking, like the dme is saving adaptations somehow.
-
unless you have different injectors and know what you are doing, leave min pulsewidth alone. try removing positive cable and touch to negative for around 10 seconds, that has been working for me on jtec ecm's, i tested this procedure many times and it seems to make a difference
-
They are 29# injectors, stock was 21#. I’m going to try touching the cables tonight.
-
you know what they came out ?
-
What do your fuel trims show in scanner?
-
They are new to the motor accel injectors, motors been running for a year with them now. Fuel trims are reading zero, before I locked out closed loop they were at 8%, which I initially took out 10% fuel to make up for it.
-
what mods on the engine, post a scanner file too
-
I don’t have a current log file; she’s fully built, 9.8:1, scat crank, roller cam, head studs, ported & polish; anything you can do to a 4.0. Zero short cuts... I build Porsche race cars for a living; you’d think a Jeep would be pretty simple lmao.
-
The pulse width should directly translate to what you put in the map. Basically under normal (idle and light throttle) conditions injector pulse-width = fuel table + battery offset + injector offset. Have you datalogged the injector pulse width before and after your change ? If so is it changing ? If so maybe you need to try a new wideband sensor. If not then very possibly you either are making changes to the area of the map that the engine is not actually running or making changes to the wrong fuel table. Have you tried copy-> pasting the EGR off map to the EGR on map?
-
i look at your file,you need to take fuel out, it looks like you added fuel to some of the idle and cruise portion of the fuel map. if you have 29# injectors you need to take out similar fuel from all the fuel map
-
It’s only to rich at idle, normal mid throttle isn’t to lean, 15:1 at times. I’m not worried about that currently, and it’s a 130 more hp then stock, it needs more fuel off idle.
-
And that fuel map I sent is 100% stock fueling other then 15 kpa section, that’s only a text map