OK guys here is the cenario:

1990 EF H/B STD
Frog jumper set up (OBD0 to OBD1)
JDM ZC SOHC VTEC with:
DC Sports 4-1 header (old EG spec)
AEM Cam gear (set at 0)
2000 EX Intake manifold
OBD1 GSR t-body
Milled (severely) and ported head
P28 ECU (virgin)
B&M Command flow FPR (set at 50psi @ WOT)
RC 270cc injectors

Heres the problem:

I can drive the car as hard as I want under 65% throttle with no issues, any gear any speed, any RPM.

If I exceed 65% throttle the car shuts off untill I lift to under 65%.

I have tried new TPS, MAP, ECU, Injectors, double checked all grounds and wiring.

Anybody ever run into this before? Any educated guesses?

I've done a search and came up empty handed, so any help would be much appreciated.

-Dylan

 

Well for one, you're drowning the thing in fuel. Are you sure the TPS is working right... .45V closed and 3.50V or so open.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DS1 Motorsports &raquo;</TD></TR><TR><TD CLASS="quote">OK guys here is the cenario:
B&M Command flow FPR (set at 50psi @ WOT)
RC 270cc injectors
</TD></TR></TABLE>

Why are you using 270's on a N/A car?

 

My AFRs were way lean so we added more fuel then maxed out the stockers.

-Dylan

 

I think your ecu needs some attention

 

meaning?

We tried 2 different ecus, same issue.

Yes, TPS is dead on.

-D

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bunger &raquo;</TD></TR><TR><TD CLASS="quote">Well for one, you're drowning the thing in fuel. Are you sure the TPS is working right... .45V closed and 3.50V or so open.</TD></TR></TABLE>

I think its 4.5v at WOT.

Also, with the injectors. You STOCK unchipped ecu still thinks its the stock fuel injectors. I would chip your p28 telling it that it has larger injectors.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DS1 Motorsports &raquo;</TD></TR><TR><TD CLASS="quote">My AFRs were way lean so we added more fuel then maxed out the stockers.</TD></TR></TABLE>

You're using a stock P28... how were you maxing out the "stockers"? You have the fuel pressure above stock and 270cc injectors, probably around 30% too much fuel, how did you determine you're running lean?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mach69 &raquo;</TD></TR><TR><TD CLASS="quote">I think its 4.5v at WOT.</TD></TR></TABLE>

I gotta check the helm on this... it keeps coming up and I can't remember if it was 3.5 or 4.5...

Edit: Just checked it, you were right, its above 4.5V.

 

Wide band o2 (FJO)

I thought alot on that chip idea but if the pulse width is still set up for stock injectors all I should have is a over rich condition.. correct?

-D

 

How did you find out you were running lean?

Larger injectors with increased fuel pressure and the stock mapping is gonna deliver a lot more fuel than you will need.

 

When I first started the car I took it out with the FJO in it to make sure I didn't have any major issues (the car is almost 15:1 compression/ estimated).

-D

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DS1 Motorsports &raquo;</TD></TR><TR><TD CLASS="quote">Wide band o2 (FJO)

I thought alot on that chip idea but if the pulse width is still set up for stock injectors all I should have is a over rich condition.. correct?</TD></TR></TABLE>

I'm really surprised that you found a lean condition before, are you running a cat? And if so, where the readings after the cat?

A super over rich condition will wash out your rings, and you're loosing power to boot.

 

Bunger- I agree, mucho lost power, but i wanted to make sure i was clearly safe with fuel before i take the car to the dyno and risk blowing it up.

Wideband is before the cat.

My afrs are now about 11.7:1 across the board with is set-up like that for test miles on the chassis. (yes, rich, but very safe)

eda6- probably going AEM in the long run

-D

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DS1 Motorsports &raquo;</TD></TR><TR><TD CLASS="quote">My afrs are now about 11.7:1 across the board with is set-up like that for test miles on the chassis. (yes, rich, but very safe)
</TD></TR></TABLE>

VERY Rich for your setup. On a boost engine like 15+ psi, it should be 12:1. You raise that number to like 13:1. Try that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DS1 Motorsports &raquo;</TD></TR><TR><TD CLASS="quote">My afrs are now about 11.7:1 across the board with is set-up like that for test miles on the chassis. (yes, rich, but very safe)</TD></TR></TABLE>

If you're running the conservative stock timing maps, you could probably even run a little leaner than 13.0:1... say 13.5:1 or so... depends how much you shaved the head and such.

 

Even with the AFR's on the rich side the car shouldn't completely shut off if the accelerator is over 65%.

the odd thig about this is the car remains "off" untill I lift off again even though the RPMs drop.

-Dylan

 

You check your TPS? Put a meter on it and make sure its sweeping correctly.

 

Did that, checks ok all the way through the sweep. Also swaped out TPS for known good unit.

 

monday bump

 

Nobody has any other guess?

 

It's bogging under fuel. What else do you need to know?

 

with AFRs at 11.7:1 it's not bogging under fuel.

This isn't a bog, literally it's like the car shuts down (igniton or fuel) untill you lift the throttle up past 60%

-Dylan

 

Sounds like your TPS wires are backwards...
You did an MPFI swap on that car, do the TPS wires go - Green - Red - Yellow
(Looking from the back of the plug, wires coming toward you, clip up)

 

Hmm, I swear I switched them, If your right I'm gonna pay pal you enought for a case of beer..

-Dylan