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$1,000,000 if you help me spool!


Emerald Weapon
12-04-2006, 11:59 PM
I know that this is long but please read. I want to be as detailed as possible so that i can actually get some help.. thanks in advance.

I have a 96 GSX, Big16G, FMIC, intake, exhaust, BOV, stock fuel system, 6 bolt bottom end, 2g head.

So me and my buddy just finished putting in my new motor..broke it in and it ran great at 12 psi. Later on, I hooked up the MBC and decided to go for a little bit more boost.

It was a cold night and i was pretty low on gas but i wanted to finish setting boost at a perfect 15 before i got gas. I left the gas station and got on the freeway and banged through 5th gear, but i was getting some fuel cut, so I lowered the boost down a hair. Tried it again and still, more fuel cut. I took the MBC off and hooked up the vacuum lines like stock, and still, more fuel cut.

Next day, I go to drive my car and it sputters like shit as soon as i hit 3000 rpms, i cant go past 60 mph.

I think to myself "boost leak!". Pressure check it, but nothing leaks except a small tit on the intake manifold. connect the hose, and drive.

It gets worse..the blue 100 amp fuse for my alternator blows and my horn honks everytime i turn my headlights on..wtf?

but i notice that with this 100 AMP fuse blown, i can actually drive past 3000 rpms and hit boost from about 4500 to redline.. so im kinda happy, except for the fact that my radio wont play and my battery is dying..fuck that.

I replace the fuse, and the hardcore sputter comes back. I get a CEL (P0135- front O2 sensor).

Time for a hardcore tune up. I change my spark plugs (NGKs gapped to .28), NGK wires, new fuel filter, used O2 sensor (but mint compared to my old charcoal black one).

I figure the car should run better, but no luck. Still the same thing, wont go past 3000 rpms. I can tell the car is running extremely rich, exhaust smells rich, black in color.

Thought maybe an injector was stuck open. Disconnect them one by one and each one affects idle so i guess not..

Replaced my CAS, double checked my CAS wiring but all solders are mint and insolated to perfection.

So am i fucked or what?

The last thing im about to do is is switch out my MAS, then call it quits forever and burn this fully built awd slut to a smoldering chassis.

just kidding about the million bucks too :/

Blackcrow64
12-05-2006, 12:07 AM
It gets worse..the blue 100 amp fuse for my alternator blows and my horn honks everytime i turn my headlights on..wtf?
:rofl:

The moment I read that, I hit the floor laughing. That is the greatest thing I've ever heard!


just kidding about the million bucks too :/
Damn... And here I thought this thread would be the answer to all my problems. lol



Well... I'm not real sure what to tell you. You have a very interesting and unique problem here. Are you 150% sure that you wired up the CAS correctly?

EDMUND65
12-05-2006, 12:07 AM
I'm sorry but even for a million dollars i dont think i could find the problem... welcome to the forum!

Thor06
12-05-2006, 12:39 AM
Yeah, dont make rediculous thread titles like that.

Did you do a boost leak test? Timing belt jump a tooth or two? How do you know it was hitting fuel cut? My guess is it wasnt hitting fuel cut (stock boost on a b16g wont get you to hit fuel cut, shit neither will 15 psi at least not on my Talon) I had a plug wire grounded out once so it was running on 3 cylinders. It ran fine from idle to like 3.5k-4k but after that it jolted and fell on its face. Check that out.

Emerald Weapon
12-05-2006, 01:02 AM
yes i did a boost leak test..
It was hitting fuel cut when I was inbetween adjustments on my MBC and boosting more than 15 psi. Then as I continued to lower boost, I continued to feel what I can only describe as "fuel cut", or a rather sudden break in acceleration while approaching full boost. It might not be fuel cut exactly, but it led up to me not being able to even accelerate past 3000 RPMS.

I doubt timing jumped because my car accelerates fine with the alternator fuse removed. I also replaced the alternator by the way.

Might the 100 amp fuse be linked to another sensor that affects my fuel/spark in any way?

As far as DSM sensors go Im no master..

It makes no sense to me that when I remove a 100 AMP fuse, my car runs better than with the fuse installed.

And I thought for sure no one would take the million dollar title seriously. My appologies if you were offended, or otherwise duped into reading this thread.

defiancy
12-05-2006, 01:13 AM
I have a 96 GSX, Big16G, FMIC, intake, exhaust, BOV, stock fuel system, 6 bolt bottom end, 2g head.




That might be your problem. I would go out and atleast get a 190lph fuel pump before you run anything more than stock boost on that 16g. I would go with a 255lph HF if it was me. You have alot of power adders and no where near enough fuel.

Under normal circumstances it might not to be that but. But since you are running a FMIC and a 16g, you definately need some more juice.


Also, check your mechanical timing, it sounds like you may have skipped a tooth.
Timing belts stretch when they are new and since you said you just rebuilt the motor, I'm assuming you have a new timing belt. If you didn't shame on you.

The alternator runs directly to the battery, I don't know of anything offhand that is connected soley to the alternator. Most of it is connected to the battery. Test your battery see if it's good, It could be getting overcharged from your alternator.

Seems like a very strange thing to happen out of the blue. The only other guess I could give you is maybe somewhere in a wire bundle you have a short with the alternator wiring, and it's giving way to much power to a system and causing it to not rev over 3k. And once you remove that fuse that wiring or system isn't getting that extra juice anymore.

Emerald Weapon
12-05-2006, 01:28 AM
Additional fuel is a must. Like I said, I removed the MBC and routed back to my BCS for a very safe, stock boost level. Still sputters though :/

And of course I used a new timing belt, OEM mitsu all the way :)
Im going to double check timing tomorrow..

BTW, with skipped timing would I be able to drive normally to 3000 rpms, sputter from 3000 - 4500, then make nice, full boost from 4500 - redline?

because thats exactly what I can do (with 100 AMP fuse is removed)

gthompson97
12-06-2006, 01:42 AM
If you skipped a tooth, it wouldn't run correctly at all, in any gear or any rpm. Do you have access to a different battery and different ECU? Try swapping out those two and see if it changes anything. Fried batteries and messed up ECU's can cause some very, very weird problems, especially in these cars.

And before you burn it, let me pick a few parts off of it! :D

Emerald Weapon
12-06-2006, 07:14 AM
I changed the MAS with the old one from my 99 GST that I know worked and still no change..

Im definately considering the ECU.. Id just hate to have to take apart my center console (and my friends) to swap them..

By the way, has anyone ever heard of the MDP (manifold differential pressure) sensor causing a super rich condition? Its the little one on top of the intake manifold I believe.

But yeah, I think im fucked...maybe its time to just give up and visit an auto electrician..

defiancy
12-06-2006, 04:43 PM
I changed the MAS with the old one from my 99 GST that I know worked and still no change..

Im definately considering the ECU.. Id just hate to have to take apart my center console (and my friends) to swap them..

By the way, has anyone ever heard of the MDP (manifold differential pressure) sensor causing a super rich condition? Its the little one on top of the intake manifold I believe.

But yeah, I think im fucked...maybe its time to just give up and visit an auto electrician..


I don't even think that sensor is plugged in for me, so definately not that.

I would think it's a wiring problem or as stated above the ecu etc.

Black99GST
12-06-2006, 04:53 PM
fuel curve is F-ed w/ stock fuel pump :2cents:

darkvader248
12-10-2006, 09:43 PM
The last time my car hit fuel cut like that and was limiting me to around 60mph my speed sensor was bad my speedometor needle was bouncing all over the place

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