jinxed4dub

iTrader: (7)

For those of you who don't know car is a S4 T2, Cork sport DP, 3"-2.5" flange, hollow cat, Apexi N1 Catback, 3" TID, FD fuel pump, 720cc injectors, Old school FCD,

Problem is my car is leaning out (wide band says so) and falling on its face. mostley in boost but out of boost too. problem is getting much much worse. I've rewired the fuel pump, swaped fuel pumps, still no go. Boost hits and it AFR's go to 10:1, probably richer since thats as rich as it can read. then flys up to 15-17:1 AFR's and back fires and sputters. This needs to go away asap. I've been looking for months.

Possable things could be the positive 10G wire from the alt is spliced since it was hard and brittle and causing a simular issue before. ececpt that car would start and run fine for 10 minutes then would spit and sputter constantly. I tryed running a new wire from alt to fuse box but the car wouldn't start, I got no power to the ignition like that. I have a spare alt or 2 laying around somwhere also maybe I'll swap. I'm thinking possable voltage drops. I know I have an unknown power draw of some sort also. not sure where to start looking for that. Also maybe the main relay is bad since thats what triggers my Rewired relay. I've double checked all my wiring for the fuel pump and all is good. all connections are soldered.

Nick_d_TII

iTrader: (6)

What RPM is this happening? Secondaries all plugged in and getting good connection? When was your Fuel Filter Changed?

My truck was running like **** once and one of the injectors was plugged in but it wasn't getting an electrical connection, ran like junk... sputtering and crap...

Good luck...

jinxed4dub

iTrader: (7)

any RPM, I've changed injectors since this started, so I'm pretty sure thats not the issue. Problem is so bad car is basically undriveable now. I step on the gas it goes lean. I spent last night redoing the fuel pump to make sure its all wired up right. seemed all good. problem still getting worse.

Nick_d_TII

iTrader: (6)

Did you try it w/o the FCD hooked up?

KompressorLOgic

iTrader: (6)

u sure its not fuel cutting? ( i had a fcd that i put in once that didnt work)
what ecu are u running ?
how much boost?
is your timing set correctly?
is your tps set correctly( does it ohm out correctly for full throttle at like 5K ohm )( u can try running with it unpluged it should default the ecu to 100% throttle) see if it drives any better.
is the boost sensor hooked up? ( does your in dash boost gauge work good indicator if a line has blown off)
remoe the fcd see if problem persists, a

nother thing u can do is unplug the boost sensor electrical connection it will default the ecu to 4 psi, see if it drives any better, i wouldnt go hauling *** tho since at higher hten 4 psi timing will be off but u can do a bit of testing.
does your car get this problem at below 3800 rpm also?
you mention its pegging your gauge out on rich...
keep in mind if your going so rich that it misfires, that will give u a lean spike on the wide band( probbaly not what your seeing from the sounds of it)

jinxed4dub

iTrader: (7)

it could be going so rich it misfires. its for sure a misfire one way or another. but it feels like fuel just shuts off. this happens at any RPM, and out of boost aswell now. it use to be only higher boost levels, and every now and then, then it was more often than not in boost only, now its all the time in or out of boost.

Boost is set to 10 but I'm about to go remove the waitgate so it doesn't boost at all untill I get this fixed. I'm running a stock S4 T2 ecu, its the right one. TPS is good, I've checked all vaccum to the pressure sensor. I'm gonna limp my car down to marks and check my fuel pressure. see where I'm at.

barney1omm

iTrader: (19)

call me . jinx .... i missed your call ... and deleted # on acident .. stage 2 turbo goin on sunday .. boost u

jinxed4dub

iTrader: (7)

Yeah, I'm gonna save my pennys and get a bigger turbo, with manifold and external waistgate. But must figure this issue out first.

So I've decided this must be a fuel issue, if I have a full tank the problem goes away till it drops do 3/4, then its only in high boost sometimes, if I'm below a half it does it all the time, below a qtr bogs and dies out of boost. So I'm thinking the 255LPH ripped appart the stock regulator, and when theres enough fuel over the return line it allows enough pressure to work. So I have a sard rrfpr, a new fuel filter, and a banjo bolt to get rid of the pulsation damper. hopfully this fixes the problem. fingers crossed. I still have my waistgate open constantly to keep from boosting too high.

Any one know what I need to set my base pressure at? I have rewired my fuel pump, and got rid of the box that drops voltage to 8 volts during idle, so I'm always at max voltage. I'm running 550 Primarys, and GSL-SE 720 secoundarys.

barney1omm

iTrader: (19)

might be partin super 7

jinxed4dub

iTrader: (7)

what did you do now bruce?

barney1omm

iTrader: (19)

coolant seal ...

jinxed4dub

iTrader: (7)

Alright so Hopfully, I'll have this issue fixed by tomarrow. I'm thinking its my fpr. If I have a full tank I can boost fine, if its down to 3/4 it will cut after 9 but only sometimes, if its less than a half tank it will cut after 7 more often than not, and if I'm down to 1/4 or less it will do it out of boost. so I'm thinking the weight of fuel over the line is keeping some sort of pressure to drive around.

Thanks to NickdTII and derekcat, for the parts.

Nick_d_TII

iTrader: (6)

Hopefully it works out for you!!

Barney, You should take it apart and replace the coolant seals only. Some might say bad advice, but I'd like to know how many miles they last after replacing the 'head gasket' since really thats all the coolant seals are... I figure that at ~100k miles the rotor bearings and rotor seals and housings have a good amount of life left in them and if you just don't touch the ****, it should run fine for another ~80-100k with the factory seals/housing/bearings. (if it aint broke don't fix it mentality)
But everyone just decides to 'REBUILD' when the 'head gasket' or coolant seals go, which takes the cost and complexity of the job through the roof... but it's what I did, and I think the seals looked pretty good, but I just replaced them anyway...?

leftcoastdrifter

iTrader: (17)

that's the advice i gave him last time with his first motor and he wouldn't take it. instead he bought another "good" used engine. guess that didn't fair to well. i feel the same way you do, it might be a little cheap and ghetto but if your building a car to just enjoy driving it then weres the harm?


there's no weight of the fuel on the line. the line comes up and out of the tank. i think you got yourself a crappy FD pump like i used too. or a little of everything that you mentioned. if you still live in Salem you could bring it by my house and we could have a quick looks see. i have all the tools in my garage for a quick check up and even a homemade code checker i got from Apex944 when i lived in Sacramento.

jinxed4dub

iTrader: (7)

No this is happening with more than one pump (Stock, TRE 255 LPH, and the FD pump), I've tryed 3 now, so its not the pump. the return line drops below the fuel level, there is weight of the fuel over the return line that would create some sort of resistance, not much but some. like I said full tank wont bog at all, half tank will sometimes, around a qtr tank almost every time I boost above 5, and if theres less than that, it will bog every time I press the peddle in boost or not.

leftcoastdrifter

iTrader: (17)

are you running the right fuel pump assembly? S4 and S5 have different heights which would starve the pump at lower fuel levels. or in any case, are you sure the pick up is sitting as low a possible? it should be sitting a little above the bottom of the tank. if it were to high it could cause problems like your describing, it'd only have to be a little off.

joemaddox

iTrader: (52)

hey i have a FD pump in beckys car, and i have found that (she ran it out of gas once and we all freaked), but we have found that the cars tank will not register the same with the fd pump in it.. Qtr tank is empty.... I checked to see if it was and not a broken gauge and it will not pull fuel correctly and will run EXACTLY as you are describing... Its one of the two problems i have encountered with beckys car.. and it seems we have near the same set up, so maybe that is it?? Just a thought... But i dont really know, its all i could think of

jinxed4dub

iTrader: (7)

my gauge is off, but I know it well, And its reading exactly the same as always, 20 bucks from E pops it to just over 3/4 of a tank on the gauge, witch is really just above half, half is really about a 3rd, full tank is above the fuel symbol about an 8th inch. also I'm not sure if I said this but the baffels are not rusted out so its not an issue, doesn't cut on hard corners left or right.

its the same pump carrier as its always had, prior to this issue. problem is getting worse, rather than the same, so it has to be a failing part thats getting worse. car sat for two years prior to me owning it and I've been dayly driving it just under a year. I haven't replaced the pulsation damper or the regulator. I didn't get around to getting my car appart today, had too much to do. better luck tomarrow. Also I'm pretty sure my pump is lower than stock since I'm not using the rubber piece. the problem also was going on before I removed the rubber, Its secure so its not boincing around at all.

leftcoastdrifter

iTrader: (17)

how man times have you tested your fuel level theory?

jinxed4dub

iTrader: (7)

my gauge, or the issue itself, Both of those I've seen for my self. with a full tank it just won't do it (I've tryed). I suppose I could just keep a full tank, but thats harder than you would think since I go though 20 bucks of fuel a day on average.

barney1omm

iTrader: (19)

can i try silver seal 1 st / ?

jinxed4dub

iTrader: (7)

bruce coolant seals are less than 200, just do it,

so I tore into it found the pulsation damper had failed (surprise surprise) and replaced the regulator with the sard, I'm not sure if it cured my problem yet, I have to put the waistgate back on tomarrow. But it did fix my low idle, I now Idle at 750 from 450-500. so looks promising so far. wish me luck bro.

jinxed4dub

iTrader: (7)

Well, there was deffinately some issues fixed, I'll let you know more when I hook the wastegate back up. but more power all around, cruises much better, I don't have to be over 3 grand to accelerate. Much better. Thanks nick. Also its not leaking as far as I can tell. we resealed the barbs with thread sealer because the teflon tape was being eaten away.

jinxed4dub

iTrader: (7)

still occationally going lean on me, still haven't hooked up the waist gate. I'll change the fuel filter next. I'm beginning to think I just need to swap the engine harness. even when I'm cruising my afrs are all over the place. sometimes its sitting in the 12's sometimes 14, some times 15. this is at about 60 mph. it stays 14.1-14.3 with occational spikes to 15's you can feel the engine studder when it does it also.

leftcoastdrifter

iTrader: (17)

how's your alternator and what voltages are you putting out at cruise when your having these spikes?