running lean, issues. Diagnostic info inside to help.

[S13CoupeLover]

So I have a '90 hb with a '96 obd1 ka24de swap. Having a little issue with it running lean, I and a few others are assuming.

Cold start it kinda jults, bogs, sputters, whatever you want to call it when you start in 1st gear from a dead stop, mainly if it's a low rpm start i.e. around or under 1krpm. Then at driving normally it runs fine. WOT it starts to loose power around 3k? i'm guessing, rom gauge i'm running now is a sohc so not working right now. But, it does keep revving, just lose of power.

Mostly anything under load, wot in a higher gear, low rpm starts, etc.

So what i have done to find out whats wrong:
Maf at idle is around ~1-1.1v
Maf at wot ~3.5v
Tps seems fine, idle .38=Idle. wot ~3.68
O2 is showing under any tps OPEN scenarios running lean ~.0v (af base 101) and decel. rich ~.8-1v (Af base, 100)
Fuel pump (0-100psi gauge hard to tell) ~40-45 wot no drops kinda risses. Changed that out (just to make sure) and still the same.
Duty cycle idle ~1.9-2 Wot ~54.46
AAC idle ~13 Wot-~24
injector idle ~2.86 Wot ~13.37 (data scan/consult info, no idea of type of measurement, ie v, ohms, etc)
timing (off of data scan also) idle ~12 (timing light says ~20) WOT ~16 and around .8 of throttle it spikes to ~44


Measurements off of Data Scan/consult that I do not know the type of measurement, ie volt, ohms, %,etc:
-Af base
-AAC
-injector
-timing... i remember some where that ecu reads different timing then pulling timing off of timing light. true? not true?? dunno.


Help with anything is better then nothing. THANKS.

[Sx-mad]

The timing should match the consult regardless.

If you lock the timing and set it to what the base timing should be, whatever the ecu says it should match the timing light.

[S13CoupeLover]

so i should probably set timing to what it says on consult?

[cotbu]

It's called syncing! Sync your timing with the consult program. And set the tps to factory voltage. Get a wide band afr sensor and gauge, me trying to explain a/f base would fail horribly.

You do know what the base timing is for a ka24de is, right?

[S13CoupeLover]

Didn't see anything about "syncing" on Data scan, it was either synced with the ecu or not. Tps is, according to FSM, in tolerance. And... stock timing is 20 degrees BTDC. I'll probably go back and redue timing to what consult says.

[cotbu]

OK last try, adjust your tps to .45v and I wont say anything about the other stuff that's screwy with your setup! g/l

[S13CoupeLover]

i don't understand... according to FSM tps is with in spec. FSM- TPS at idle .3-.7v and WOT 4v. What i get is Idle .38v and wot 4.14v.

And what else is "screwy" with my setup??

while looking at my data logs and checking with FSM data, only thing i see weird is injector pulse at ~2k rpm is off FSM= 2.1-2.8 what i have is 4.6.
At idle it seems fine at 2.86 and FSM says 2.3-3.

and if AF base is the same as AF Alpha on the FSM then that's in spec. FSM @2k rpm-51-160% ans i get ~101.

[cotbu]

Help with anything is better then nothing. THANKS.
----------------------

[Kingtal0n]

I think your main problem is that data scanner tool. Pretend like it doesnt exist for a minute.


You say the engine runs lean during wot. Have you verified with a wideband? Wait- you said N/A KA engine. No sense in buying an expensive wideband or assuming the engine runs lean. Lets take another step back.

This is what I would do:
#1 install new narrowband oxygen sensor
#2 install new spark plug and inspect ignition delivery system (wires/rotor/cap)
#3 put some fuel injector cleaner in the tank
#4 do a compression check verify all cylinder are even
#5 follow FSM proceedure for setting the ignition timing

[Kingtal0n]

i'm guessing, rom gauge i'm running now is a sohc so not working right now.

Also, what does this mean? you have a tool for a SOHC ka and you are trying to use it on the dohc ka?

[Sx-mad]

You definatly don't have any leaks between the afm and the throttlebody.

The only thing I see wrong so far is your injector percentage. On my sr20det it idles at around 1.5%

[S13CoupeLover]

This is what I would do:
#1 install new narrowband oxygen sensor
#2 install new spark plug and inspect ignition delivery system (wires/rotor/cap)
#3 put some fuel injector cleaner in the tank
#4 do a compression check verify all cylinder are even
#5 follow FSM proceedure for setting the ignition timing

1- haven't done this yet.
2- spark plugs are new, already checked resistance on wires. caps/rotor is newer also.
5- i know for sure it;s set correctly.

I have some things to try first but, if they don't work out i'll give 1,3,4 a check also.



Also, what does this mean? you have a tool for a SOHC ka and you are trying to use it on the dohc ka?

lol. ment i'm running wrong gauge as of right now. Sohc gauge with a dohc.



You definatly don't have any leaks between the afm and the throttlebody.

The only thing I see wrong so far is your injector percentage. On my sr20det it idles at around 1.5%

Checked for leaks, pluged/fixed all the ones i've found.