ok, the car runs pretty strong overall, however, i've noticed that when the car is under load and it begins to accelerate, once it hits 0psi it begins to hesitate and stutter a bit. if i stay on it, it usually picks itself up and starts to pull again. an example is: say i'm cruising in 3rd at about 22-2300 rpms and i try to accelerate from there. if i put the engine under a load, giving it about 50-75% throttle, it will slowly start to pick up, but like i said, when it hits 0psi it starts to hesitate. kinda like if you're really low in the rpms(under 2k) in 2nd or 3rd and you just stomp on it. you know how you get that jerky hesitation? that's what it feels like.

now, the only thing i can think of is a)i've been thinking that my coil is in need of a replacement for a couple of months now, but there's hasn't been a whole lot of reason to replace it other than a rare occasional misfire here and there.
b) right at 0psi, is where the static setting on the sfmu kicks in and the 5:1 rise begins... maybe it's getting bogged down b/c the static is too high. i thought this might be the case and tried turning the static down a bit a couple days ago, while viewing the fuel trims at the same time, and the only way to keep my stft close to 0 at idle was to set it the way it is right now. the other thing is, if i just accelerate hard or under normal load, it pulls real smooth through every gear w/ no hesitation whatsoever. i haven't been able to do any real wot pulls yet(crowded ny highways), but i did one wuick yesterday and i think* i saw the o2 V go to 1.000, but i was only wot for a sec or so, so i can't really go on that as a real reading. i don't notice any black smoke when accelerating hard, but i have to do some long wot pulls to be sure. anyway... any idea on this problem? oh yeah, and my stft on all my datalogged runs has been right in spec throughout. sorry for the long post

- Dan

HRC Stage 2|30lb injectors|S-FMU|Walbro255HP|AFX UDP|B&M Short Shifter w/ Symborski Shift Kit|Rear Strut Bar|Power Slot Rotors|more...

bump... just drove and now i'm thinki'n it feels a bit more like fuel cut, however, if it was wouldn't it do it all the time and not just under extreme load? also did a wot pull and my a/f voltage was .97-.98 ... rich, yeah, but just to make sure it's accurate, for those of you that have an a/f gauge, when you're engine breaking at 4kish rpms does the a/f go into the negatives just a little bit? mine does for a sec or 2.

EDIT: ok, a bit more info... as i'm looking at the data from the drive i just took, it seems that everytime the "hesitation" occurs, which is only for a split sec b/c i immediatly let go of the gas, my map reading on the chart is always over 100. not much though, it's about 101.xx to 102.xx . i'm n ot sure how the datalogger measures the map. i mean, the ecu should never see more than 5v from it correct? so what does 5v map over to in the datalogger data? i'm thinkin' 5v=100 on the table, so over 100 is over 5v. i'm confused either way though, b/c it ONLY happens under load. like when the load is 50+ or so. well i'm gonna stop talking to myself here and wait for a reply, hehe.

- Dan

HRC Stage 2|30lb injectors|S-FMU|Walbro255HP|AFX UDP|B&M Short Shifter w/ Symborski Shift Kit|Rear Strut Bar|Power Slot Rotors|more...

What datalogger are you using to read your fuel and MAP info? What is the MAP reading in? If 5v = 100 then your MAP sensor might be at fault, or your missing link if youre using that. It sounds like youre almost running too rich at the RMPs that cause the hesitation. Did you check your wires? How does your timing look?

NeoVB
2005 Subaru Impreza 2.5RS
1997 Mitsubishi Eclipse GS TURBO
1995 Mitsubishi Galant ES DOHC TURBO
1991 Eagle Talon TSI AWD

Yeah, it really sounds like fuel cut. if you have a missing link make sure the bleed hole on it is clean, if its not it could build up unwanted pressure and send a bad signal to the ecu that would cauce the cut.

____________________________________________________
four nails four corners four riders and four horses

if your running really rich you could be loading up with to much fuel and that would cause the hesitaion and it would slowy accelarate after the hesitation. it just an idea because i was experiening the same type of problem.

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ok... i'm using the pocketlogger, and i'm not saying that 5v=100 on the pocketlogger, in fact, now that i think of it, it would be 4.5v=100 if my assumption that 100= max volts the map should send. either way, there's now proof behind it, that was just a conclusion that i myself was drawing and was asking for confirmation. i don't really think it's too much fuel at that point, b/c why datalogging results show the fuel trims being just fine throughout any runs except for rare instances of high stft #'s(+ or -). even so, the trims at the point of my "hesitation" are never too extreme(no more than +-7). i have a feeling that i have a bad connection somewhere in the wiring of my o2 gauge even though i just redid the wiring for it, b/c it seems to always be about .02 greater than the voltage the my datalogger shows at the same time. anyway, the only thing that is constant throughout all the places i've gotten the hesitation, is that my map reading is 100-102, and it's not that high at any point where the car was driving fine. i'm sure it's fuel cut.. my question is why is the ml letting pos press through only at 0 psi and ONLY under load(usually when i hit boost while rpms are around 2500 or less) . i'm guessing that there isn't enough pressure at that point to close the valve and in turn it lets boost through. has anyone else have this happen, while hitting boost in low rpms? it's weird b/c it doesn't always happen, but if i keep trying it, it will eventually happen and then happen consistently after that. really weird, i'm going to take off the ml now, and try to clean it out and soak it in silicone spray and wd40 or something.

- Dan

HRC Stage 2|30lb injectors|S-FMU|Walbro255HP|AFX UDP|B&M Short Shifter w/ Symborski Shift Kit|Rear Strut Bar|Power Slot Rotors|more...

well it seema to be gone. i took out the ml and cleaned it w/ carb cleaner. then soaked it for about a 1/2 hr in silicone and wd40. i think it worked

- Dan

HRC Stage 2|30lb injectors|S-FMU|Walbro255HP|AFX UDP|B&M Short Shifter w/ Symborski Shift Kit|Rear Strut Bar|Power Slot Rotors|more...