Speed PHreak

Ok, seeing as how NOTHING can ever go right. I'm faced with another problem that I can't quite figure out. Lets start from the beginning shall we? Most of my problems started when all this occured. If you'd like to know all the back ground I'd suggest reading that post.

Now from there I have some how managed to a find totally new a different problem.

Symptoms: Car runs strong in lower RPMs(sub-4500) on and off boost. But then, I get sparadic leaning out. The car doesn't totally lean but, it jerks and surges when it get above 4500 in boost(9lbs). Although above 4500 out of boost it runs fine. Only does it when i'm accelerating. I've come to believe that it is a fuel delivery problem. Now I was driving home and noticing my A/F guage, while very lighty accelerating in 5th the A/F would look ok(stoich-rich), but have an very unnoticeable spike to total lean. You couldn't as much feel it, but you could see it on the A/F monitor. When pushed harder though it was a different story, more buck, detonation, etc Does it in every gear depending on the load, but 5th is easiest to notice.

Now, before all this started occuring I was trying *AGAIN* to wire up my 3 bar GM MAP sensor. How i've got the wiring wrong 2 times I'll never know. Anyways. I wired the GND and 5V refenece up backwards so the circuit was inverted. Hence the MAP thought it was MAX boost WOT = injectors at 100% duty cycle. How 100% duty cycle insn't good on injectors granted, it actually ran/idled, not well but it did.
Ok now here is the kicker, while running at idle the fuel pressure was at 1~2 PSI. I thought my guage was broke, now way could that be right. So I revved it up, fuel pressure still at 0, gas spaying out the tail pipe 10 feet or so. Then it ran slap out of gas.

So I put some gas in it from a can I had at the house(87 octane). And I reconnected my stock MAP sensor afterwards. Just plain wouldn't crank, so I swpped out plugs, the ones that I had been washing with gas just plain wouldn't spark. I reluctantly fired up, smoked and idle roughly then started to smoothen out. Ok so i took it up the road to see how it ran, and it started with the symptoms I described above.
~ Replaced the plugs.....no good
~ So I chalked it up to the low octance gas, went and put 93 in it.....still does it.
~ OK I though maybe my tuning was wrong, so I upped the fuel on my Zdyne. The more fuel I gave it the worse it got.
~ Next it got some STP fuel system cleaner, maybe there was some water in the fuel....didn't help
~ Next was 1/2 tank of 100 octane race gas.....still didn't help. So it's not the gas apprearently
~ Perhaps the fuel filter is clogged, replaced it....still didn't help
~ Reset the ECU...no good

Whats that leave? injectors or the fuel pump. Why? it runs perfectly fine at idle/off boost at any RPM from what I can tell where the flow/duty cycle isn't that high. I could have messed up the injectors by running them 100% or burnt up the fuel pump by running it that out of gas.

Any thoughts?

Your H-T dumbass
Steven

Xerxes

hmm you said that the more fuel you gave it, the worse it ran.. does this mean that even with increased fueling, it would still sporadically lean out under boost?

what happens if you run lower boost?

i assume you're using 440cc injectors, is this true? what's your fuel pressure?

-Xerxes

Speed PHreak

Fuel/Ignition setup

MSD ignition(coil, cap, 6AL)
Zdyne Standalone
DSM 450cc
40 PSI fuel pressure

Well, it seems like the more fuel demand I created by increasing the fueling setting with my Zdyne the sooner the aforementioned problem started to occur. If I lower the boost the problem still occurs, just later in the RPM band.

I'm hopeing that swapping out the HF fuel pump for an Integra, and swapping to 720cc injectors will remedy the problems

ATurboCivic2NV

LATER IN THE RPM YOUR VTEC WILL KICK IN AND THEN YOU HAVE A DIFFRENT FUEL SETTING!!

SIK IN DA HED

could it be the injectors?

Speed PHreak

ATurboCivic2NV: I'm not flaming but...
first off, find the capslock key dude...
and secondly, pay attention to the signature please.

P.S. ~ VTEC is overrated, boost is the REAL replacement for displacement !

dlplayboy: Could possibly be, i'm gonna change out the fuel pump first and see if that does the trick.....could be partial failure of the stock HF fuel pump. I've got an Integra pump that I just haven't had the gumption to install....guess I don't have a choice now.


[Modified by Speed PHreak, 9:57 PM 3/18/2002]

DIRep972

iTrader: (1)

wish I could help u.. but heres what i would try.. first thing I would do is try putting it back towards stock 1 item at a time.. the cam gears back to stock settings, put the stock map sensor back in, and so on and so on until u find out whats wrong.. currently u have a very complicated set up and trouble shooting stuff is gonna be hard.. it will probably be something simple and stupid in the end, good luck

Speed PHreak

LoL, stock? lemme go dig that blown HF motor out of the junkyard then....... heh heh. I understand your POV tho DIRep972. It could turn out to be something stupid, but this time I doubt it. The last time it was running just fine then quit. Now it hasn't been running right ever since I f'd with the GM MAP sensor....which I paid $60 bux for and most likely fried the damn thing...... Troubleshooting this car IS A PAIN, just becuase it's a complicated setup......time and persistance fixes most things tho. Wish me luck.....

DIRep972

iTrader: (1)

haha not stock like that but just try to make things more simple..

Speed PHreak

Thanx for all your help guys, i'll update you when I know more.

DRAGLS

grab your plugs gap them to .025" and let me know what happens don't question it just try it.