1994 SL-TT, the turbo conversion was all done with stock turbo parts with the exception of the fuel injectors which are 450cc. Stock turbo fuel pump (not hotwired), NA FPR. I kept the NA ECU and NA harness (resistors added to harness for fuel injectors). NA heads, NA intake manifold. I am running an e-manage blue, and ONLY a single LC-1 wideband, installed just before the CAT in a 3sx turbo downpipe. The bungs in the front and rear precats (both gutted) are capped, and do not have o2 sensors in them, the ECU is getting o2 signal from the LC-1 wideband, from one of the narrowband outputs the LC-1 has. I am only running wastegate pressure at this point, so I know the 450's are a little over kill, but I plan on about 12-14 lbs. of boost in the future.

Here is my issue, I am getting a "surge" that feels like fuel cut during cruise. It is very short, but happens fairly often, and is VERY annoying. When the events happening, the spikes in AFR from 14's, to 22's. No change in TPS, airflow in/out, IDC or injector duration when it happens. What do you guys think is the cause?

_________________
1993 3000GT VR-4 (build in progress)
1994 3000GT SL
Lead, Follow, or get out of my way!

Also know as:
"dead weight", "wrong wheel drive noob"

So the O2s go lean which means there's no fuel in the mixture. That means no feul is getting into the cylender for a moment (and that's why it sudders).

I have a suggestion for you, but you're not going to like it:

Put the stock injectors back in (leave the resistors for now) and remove the e-manage. See if it goes away.

yes, that much i know, but i really want to know why it "has no fuel" when evenything on the e-manage says the injectors or doing their job. Do you think i could be doing too much correction with the NA ECU? 210cc to 450cc?

_________________
1993 3000GT VR-4 (build in progress)
1994 3000GT SL
Lead, Follow, or get out of my way!

Also know as:
"dead weight", "wrong wheel drive noob"

No. There is no such thing.

are you running out of pump?

_________________
Bad decisions make good stories.
Look at it! LOOK AT MY @SS AND TELL ME IT'S PRETTY!

gosh, I wouldn't think so, when it does it, I am not even in boost. Heck it even does it in first gear while going slowly thru a parking lot.

Not sure if it is related or not, but the car also has a problem starting, most of the time I have to pull the ECI fuse, crank the motor for 7 seconds, but the fuse back in for it to start. So, it is flooding out at startup.

_________________
1993 3000GT VR-4 (build in progress)
1994 3000GT SL
Lead, Follow, or get out of my way!

Also know as:
"dead weight", "wrong wheel drive noob"

I guess I'd agree with the Mad Scientist here Johnny.

If you're flooding, that makes sense that it could be the issue.

Have you dialed the eManage back as lean as it will go?

SJ

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Racing is life. Everything else is just waiting.

http://umg.mn3s.org

http://ummo.boards.net

sounds related to me. you have issues.

it only takes a half an hour to pull the injectors and swtich them out. save your current e-manage map somewhere, and reset everything to zeros... that will tell you if it's tune related.

then we can go from there.

_________________
Bad decisions make good stories.
Look at it! LOOK AT MY @SS AND TELL ME IT'S PRETTY!

I have the resistors added to the injector harness, you don't think that is going to cause problems going back to high impedence injectors?

_________________
1993 3000GT VR-4 (build in progress)
1994 3000GT SL
Lead, Follow, or get out of my way!

Also know as:
"dead weight", "wrong wheel drive noob"

It shouldn't be that big of a deal. At least your current issues would go away, assuming the injectors are the problem.

QFT. GTMT. FTMFW.

_________________
Bad decisions make good stories.
Look at it! LOOK AT MY @SS AND TELL ME IT'S PRETTY!

so, i have been thinking about my little issue I am having, and I got to thinking, could this be a problem with the FPR or fuel pump? Adam had asked if the fuel pump wasn't keeping up, so could it be a voltage issue to the fuel pump? MPI relay? FPR going bad? Sound responable? How do you test the volatege to the fuel pump while driving, and what should it be? How would i test the FPR? How would I test the MPI reply?

_________________
1993 3000GT VR-4 (build in progress)
1994 3000GT SL
Lead, Follow, or get out of my way!

Also know as:
"dead weight", "wrong wheel drive noob"

You test the voltage of the pump by taking the jumping the black test connector (http://www.stealth316.com/2-checkconns.htm) and measuring the voltage at the pump.

Go into the trunk and measure the voltage at the wireharness. The black w/blue stripe wire is the power wire.

You still have the NA feul pump and FPR?

TT fuel pump, NA FPR.

_________________
1993 3000GT VR-4 (build in progress)
1994 3000GT SL
Lead, Follow, or get out of my way!

Also know as:
"dead weight", "wrong wheel drive noob"

Just had another thought: When the motor surges, does the CE light come on?