My car has been acting real weird for a while now. I'm not sure if it's mis-firing or hitting a small fuel cut. I think it might be a fuel cut. Any suggestions?

Here's what's up.
When I'm cruising usually on the freeway and if I hit anywhere around 35-44% throttle, at between 2800-3200 rpms, the car will kinda hesitate or almost misfire. I have to be in either 4th or 5th gear usually doing a constant throttle around those percentages. I can see it all on my profec e 01 mapped out with e manage, everything drops and it will continue to cut in and out if I keep it constant at those numbers. The car will be accelerating and cut, then come back and even continue to cut. It feels like I'm letting up on the gas for a split second and then giving it again. the only thing I can think of is that I'm getting a fuel cut and I need to clamp the voltage in the e manage at around those rpms and throttle percentage. I was also thinking that it could be my injectors going out. I have the stockers with 50k miles.

I'm running a built motor with stock injectors, Star stage II kit and upgraded turbo hitting about 9.5 psi. This never occurs under really heavy load, just while I'm constant at about 40% throttle and 3k rpms. Usually noticed accelerating in 5th to pass someone.

Input??

So, you're using stock injectors with a rising rate regulator and an E-01 in there to act as an AFC, right?

How does the car act if you cut the E-01 out of the loop?

Is your check engine light on at all? The "fuel cut" sensation you are having may be the ECU seeing more than 4.6 ish volts on the MAP sensor. With my old fuel setups I had one hell of a time trying to prevent my stock ECU from seeing more than ~4.7 volts on the MAP sensor. I tried the Missing Link, the DIY-FCD, etc... I eventually got an 034EFI and it made things slightly better by turning the secondary injectors on slightly before the vacuum-boost transition but it didn't completely solve itself until I installed a new EFI management system which could deal with seeing boost pressure. It's very difficult to teach an old dog (the stock ECU) new tricks (dealing with boost pressure)

Those injectors are probably staying wide open at 5K rpms. :shrug

Why would you spend all the money on a built motor and all that shit and skimp on injectors?

It's most likely a fuel cut the way your describing it. If it were a misfire you would see it more consitently over other RPM ranges and speeds.

Because I bought a bike and stopped spending money to make the car faster. I just sold the bike, so I'm getting 42lb injectors and getting a new bike in a month. I have a missing link that was on the car before the e manage was installed. Since the e manage, I haven't had any fuel cut like normally seen except for this. I do have a CEL on but it's for the notorious evap leak large that plagues the 99 eclipses from the diaphram in the little thing above the fuel tank. I don't think that would be causing this.

-I was thinking it is either from the EGR,
-the injectors,
-or I need to figure out the voltage on the map and try to clamp it with the e manage.

Any thing I may be overlooking?

Get a multi meter and hook it up to your map sensor and run some wires into the car, this way you can see exactly what your map is seeing.

I checked it today with my e manage/profec readout. It's happenning around 5.00 volts on the airflow output/input. It does only occurr around 40% steady throttle, but once the airflow is around 4.96-5.00 volts, it will get a fuel cut. I'm going to try to clamp the signal from 4.96-5.00 volts at that throttle range to see if I can eliminate it. I'll let you guys know if your curious.

I also just ordered the 42lb injectors and a turbo exhaust heatshield to keep temps down under the hood.

The signal needs to be clamped to around 4.5-4.6 volts, anything above that and the stock ECU will see the boost pressure.