rbeharry

Alright guys, I've tried searching on this issue but I have had no luck and its a strange issue I'm having

I have a JDM H22 with Type S cams,obx cam gears, cold air intake, 440cc injectors, Walbro 255lph, private label manufacturing header and my intake manifold is stock but gutted with IAB's removed.

The first time I was at the dyno my tuner said at about 6300 rpm it goes very lean, like 20:1. He said my injectors were at full duty cycle and my fuelpump was maxed out. So i upgraded to 440cc injectors, removed the resisitor box and added a walbro 255lph.

So back at the dyno on tuesday for a re-tune hoping to fix this issue, it went lean again at 7200, did another run, at 6300 it did it, then at 5500 then again at 5200, and its right about there it keeps going lean. Fuel pressure doesnt drop or spike. I have the O2's disabled, no knock sensor. The alternator voltage has a slight drop at higher RPM i think to about 13.4v. It reads 14.2v at idle. When i first swapped it in it was very high at 15.3v but its seemed to have dropped now.

Has anyone had any similar issues or have an idea as to what this could be caused by because im stumped, no idea where to start now.

Any help is appreciated

Ryan

GhostAccord

What Engine management system/ECU & software are you using for tuning?

rbeharry

Chrome. I forgot to mention that when i have the manifold gutted, it was cut too far back exposing the IACV channels causing too much air and an irratic idle. I did however plug the port on throttle body that channels air for the IAC to slow the idle but im not sure if that would make a different. Also the tps HAD been broken off, i replaced it and resealed it and set the range. .5 closed throttle and 4.5 wot. Not sure if this has anything to do with my issue.

Using a p28

GhostAccord

Adding fuel to the high cam fuel maps doesn't do anything? Seems strange that you would be leaning out. Specially with double the fuel volume and an extra 100cc per injector. The stock injectors should not have been at 100% duty cycle with your list of mods. What shop is tuning your car? They should be able to help you out, they have the instant access to live data.

How does the car act @ idle without the IACV? Check your TPS voltages again.

gstrudler

It doesn't make any sense that the point at which you are leaning out was changing with no modification to the maps, let alone the fact that you shouldn't be leaning out at all with the new fueling. What are they/you using for wideband o2? I would have tried to add fuel everywhere in the maps to see if it made any changes and start eliminating problems.

rbeharry

The shop thats tuning it isnt touching the car. Its just a tuner who rents the dyno. Hes tuned another h22 with the skunk2 manifold right before mine and a few cars after mine so i dont think it could be his equipment. He had tried adding fuel to the map but it keeps changing the RPM points as to where it goes lean. If the fuel injectors cut off shouldnt the fuel pressure spike and if the pump cuts shouldnt the pressure drop? Its staying steady, no fluxuation with the pressure. Im thinking it could be alternator? With the voltage drop at higher rpm, its not sending enough power to injectors. According to the tuner, there is no sensor issues but he said the vehicle is acting like the are going completely dead.

mouab18c1

iTrader: (5)

My integra is doing the exact same thing as yours. I'm still trying to resolve it as well.

gstrudler

If the voltage was dropping that significantly I would think you'd be losing spark too and would misfire from lack of spark. A highly lean mixture means it is still combusting and is burning everything up, so I can't imagine that system power is bad. However, that does raise an interesting question about the injector drivers in the ecu. What ECU are you using? I wonder if the drivers are going bad or if you're using the wrong type of injectors, although I'm not sure how well they would function at all if they were in fact the wrong type (p&h vs saturated).

rbeharry

I'm using a P28. One thing that im thinking coudl be a possibility is my intake manifold porting. The manifold was ported too deep exposing the ports for the IACV. That port leads out to the throttle body and it allow air to get into the manifold. Could this cause excess air in the system ? Sorry there's soo many factors to me.

mouab18c1

iTrader: (5)

Have you changed your fuel filter? Or anything? I was thinking if it was an electrical problem wouldn't it occur at any load?

rbeharry

I put a brand new oem fuel filter, walbro 255lph and 440cc injectors. It could be electrical problem but it doesnt make sense as to why it does it at different RPM

mouab18c1

iTrader: (5)

Oh trust me, it's a biotch. Have you ever messed with your harness? I'm about to tear mine apart today.

00Red_SiR

Take areading on your alternator output. A voltatage regulator going bad can cause it to fluctuate at different RPM, affecting the injector output.

mouab18c1

iTrader: (5)

I also have tested my alternator out at a local shop and it was good.

EliteHeads

Try widening your lobe sep and the problem should go away. it sounds like your fuel is getting sucked out the exhaust port during overlap. this is common with good scavenging headers. Are you tuning open header?

rbeharry

I have the private label manufacturing header, its a little crushed at the bottom with a 2.5" straight pipe to a vibrant flat black muffler. I highly doubt its due to the header because i had this header on before i did the manifold and cams and i didnt have this issue.

GhostAccord

What are your cam gears set at?

rbeharry

ZERO. Have not touched them at all

mouab18c1

iTrader: (5)

Could it be timing related?

h22crxpwr

what fuel rail are you using? Oem? i actually saw a clogged Oem fuel rail and you couldnt tell by looking at it or anything. .. took forever to figure it out.. try changing it. good luck!

rbeharry

I'm using a stock fuel rail. I didnt have this issue until I replaced the manifold and put in the type s cams. Would a vacuum leak cause an issue like this?

DSDoneJimmy

did you find out a solution to this problem. mines is leaning out at 6500 rpm on a H2B setup

99 eg

If u find out what it is hit me up I have a b20v and it leans out when the vtec turns on..changed injectors ,fuel pump.fuel pressure regulator.fuel filter.plz help anyone....

the171

im using a similar setup. H22 with 12:1 compression and bigger cams. I have rc 440 injectors and a 255 pump. Hondata tells me that Im at 70% fuel capacity. I have no lean problems.

I would check timing and ignition timing, compression, and fuel pressure. Fix any check engine lights, oil/temperature lights and clear all errors on the laptop. The engine should run well if you have these things happening. Then tune low 13s for full throttle.

h2.4

you shouldnt be maxing the injectors or the pump on your setup. Have you tried a different wideband? When the heating elements go out on the wideband, it will give you off the chart lean readings when the airflow comes up. It will read fine at lower rpms, but once you get the airflow up it'll just read full lean. Try a different wideband o2 and see if its that.