Save my car from the firey depths it is facing...

[KATwo40]

Ok, here's the setup.

Fully built KA24DE-T370cc/min sidefeedsZ32 MAF blow-thru setupHybridKA daughterboard (Tuned for Z32/370's)SAFC2 (hooked up from before the board, but set to 0)

Here's the deal. As most know already, I installed the new engine last week and have been driving it. Everything was great.

The more I drove the car, the more I noticed the idle quality deteriorating. I attributed this to a dirty IACV and decided on Monday that I would hit the parts store after work for a can of intake cleaner to fix it right up.

The car died about half a mile from the parts store (also about half a mile from my house) and would NOT restart. I had to tow it home.

The car is pig rich now and I cannot for the life of me figure out why!

What I've replaced:

Coolant temp sensorFuel pressure regulator (stock)Injector O-rings (heavily lubed with grease) and injectors

I swapped in my STI injectors (520cc/min JECS sidefeed/high impedence) and dialed back the SAFC2 -28% (calculation comes to -28.8%).

No matter what, even with the IACV, MAF, O2 and Knock sensors all unplugged, this thing is filthy rich! I mean so rich it won't start without holding the pedal @ WOT and cranking the living crap outta the car. Then, it finally fires, revs up a little and chugs like crazy. Of course, there's a nasty plume of black smoke that continuously billows from behind.

Any suggestions here? All I can figure is maybe there's a problem with the tune on the board or the SAFC2 causing some interference. I mean, heck, the only fueling inputs are coolant temp sensor, MAF, knock sensor, TPS (also checks good) and O2 sensor, and with all of them disconnected I still get this problem.

Tomorrow, I'll pull the chips on the board and read them. Also, re-flash for the larger injectors and eliminate the SAFC2 to see how that does.

[gubermyster]

do you have a upgraded fuel pump, i had a smililar deal after getting 550's and a z32( stock motor still) but it wouldnt start up unless i gave it full gas and it was the only way i could keep it running, white smoke pouring out the back

changed the fuel pump and it started right up

hope this helps

[Poor_S13_Driver]

He said hes running pig rich. Seems like if that was the case then he has no problem getting fuel. i.e.-bad pump I dont know much about the problems that would be involved, just my thought..

[Poor_S13_Driver]

I would say that the tune is bad. At least something is somewhere. Can you try putting the stock ECU back in with stock injectors &maf, and see if that helps? Then you can start diagnosing problems from there. Correct me if I am wrong still learning

[KATwo40]

I'm still on the stock ECU, but with a daughterbaord attached, making it fully programmable. I'm going to read the chipset tomorrow and see what's going on. I've tested and/or replaced every component that contributes to fueling, aside from the SAFC2 and the ECU itself.

I'm somewhat leaning toward the SAFC2 being the culprit. Remember, the daughterboard has been the running data for the past few months, while the SAFC2 was just monitoring data and nothing more. Not adjustments were made via SAFC2.

I tried making adjustments via the SAFC2 on both sets of the injectors (370's and 520's) and nothing changed. I really hope it's as simple as removing it from the picture and reflashing the chipsets on the daughterboard for the 520cc injectors.

[Florida240sx]

if you got 420cc injectors you need to have the safc almost at -50% in low throttle to get them to fire like 270cc When I had a tore fuel o-ring on my car...I had to have the pedal to floor for it to start...Chipped ecu though could be the culprit...Got another stock ECU you can use or someone else's just for testing purposes?

Is the ecu chipped for the z32mafs? What are the SAFC settings for IN and OUT? If ecu is chipped then the safc needs to have the same numbers..... if not chipped then the safc needs to be 2 and 5

[Suicide.Veteran]

yeah, it sounds like you're fouling your plugs and o2 sensor out. What color are they? Start there then get wideband and truly adjust the safc settings. -28 correction is like for 370cc injectors as a base tune. just for measures, check the valvecover for oil, cause i had my middle gasket leak down into the plug housing and cover the plug keeping it from giving enough spark.

[KATwo40]

Guys, I'm not conveying my information correctly.

Allow me to recap.

ECU is already tuned for 370's and Z32 MAF.

Setup has been running for several months as is. NOTHING was changed when the problem occured. I swapped the engine last week, but not the tuning system, or any fuel components.

I drove a few days on the new engine with no ill effects, except for the slow decline of idle quality, and finally this rich condition.

And, so ya'll know, on a system tuned for 370's, if you step up to 520's and use the SAFC to dial back, you'll need -28% correction.

Thanks again for the suggestions and the help. Keep 'em comin'!

[Suicide.Veteran]

oh rooooooiiiiiiiight forgot about the board sorry.

what exactly is withthe idle? stumbling, low, surging, dipping? Can you elaborate more? All Ive seen is that it's deteriorating.

oooh, oooh have you had a line post MAf pop off anytime recently? it could be your MAF. Ive had to replace my z32 maf already cuz the one next to the tb popped off. They are very sensetive on blow thru setups. MAFS HAVE FEELINGS TOO YOU KNOW!!!

or check the connection voltage at the MAF and at the ECU.

I think with the MAF off it will run rich normally with bigger injectors, but maybe not depending on the way the board edits the ecu data....iono.

[KATwo40]

I have not had anything post-MAF blow off, but it does get a little bit of vibration from the cold pipe touching the battery tray where it passes through the hole.

However, with any car that's tuned for it's injectors and MAF appropriately, when the MAF is unplugged it'll at least start and run up to around 2500rpm. I can't even get that much out of it.

[Suicide.Veteran]

WTF so its super rich but hard to start? So, you're choking on fuel? Are your spark wires grounding maybe you need a new coil cuz ours are really old and weak.

[S13FX]

well he said it runs with maf unplugged, so it seems to me like it's the maf thats bad. Try and get a hold of another maf and test it out or play with the in and out setting on the safc, or better yet disconnect the AFC all together from the maf.

[KATwo40]

It runs the same with the MAF connected or disconnected -super rich, hard to start, crappy.

Tomorrow I'm going to begin by playing with the in/out settings on the SAFC (sometimes that crazy little box just wacks out on it's own). After that, I'll reflash the daughterboard chips to handle the 520cc injectors, then eliminate the SAFC from the loop completely.

[Suicide.Veteran]

i would either check the firing and ignition or see if you can borrow a MAF from someone or go ahead and buy another, cuz theyre sensetive and its always good to have a spare anyways.

[Florida240sx]

Loose wire possibily. You have an adjustable fuel pressure regulator?? Mine rises in psi every week or so. Got to keep recalibrating it...If you have an exhaust leak it will make your car run foul too...Either needs to be free flowing or completely sealed up. One point of exit only...When my dowpipe bolts backout Car won't boost for crap and car is rich...

[ghx407]

This is just a wild guess: Do you think that maybe the distributor wasn't bolted down properly during the engine rebuild and it's been slowly affecting your spark timing?

[KATwo40]

I know it's bolted down well, thanks for the offer. Keep 'em comin' guys!

BTW, ignition timing doesn't affect fueling.

[Chezedik]

I would check the MAF, it feels like a MAF to me. Since I had a very similar pro'lem in my first one.

EDIT: Can you pull codes?

[KATwo40]

Yeah, I'm pickin' up a new used MAF today for $50. I'll let ya' know how it goes. If feels alot like a MAF problem to me, too.

[KATwo40]

Well, I replaced the MAF and installed a fresh set of spark plugs today.

HOLY CRAP this car is fast! After a few pulls with the wideband, cranking it up to about 16psi, I can't keep the thing on the road!

Just kidding. Still not fixed. I'll post more tomorrow.

[WDRacing]

Well, I can toss my .02 for the record. First off, your plugs are shot. I think the cons=dition has been there the whole time, by that I mean ECU tune and SAFCII combo with the new injectors. Things got progressivly worse do to the rich condition fouling up the plugs, now they don't hardly light off at all which inherantly is making a bad thing worse. Swap out the plugs for sure, or clean the piss out of them...I'd swap them. Whats the MAF voltage reading on the SAFC?

You have a wideband right? Does messing with the settings change anything?

WD

[crzycav86]

Well, I replaced the MAF and installed a fresh set of spark plugs today.

HOLY CRAP this car is fast! After a few pulls with the wideband, cranking it up to about 16psi, I can't keep the thing on the road!

Just kidding. Still not fixed. I'll post more tomorrow.

HAHA. ****er!

WD: I think he said he just replaced the plugs.

[Florida240sx]

Take the shop rag out of your intake system??

[TrunkMonkey]

Take the shop rag out of your intake system??

LMAO!!!!!!!!! that's the image i got in my head after reading through the first few posts.

it's possible your looking in the wrong direction. all of the symptoms mentioned seem more like an intake problem to me.

-demetrius
Modified by TrunkMonkey at 7:44 PM 11/30/2006

[KATwo40]

There's nothing obstructing the intake tract. Remember, the MAF sensor is only about 8" from the throttlebody and the turbo has nothing on it's intake (for diagnostic purposes only, I put a filter on it when I drive).

But hey, what the heck, I'll go out there in a minute and try to blow through the turbo. Maybe there's a cat in there or something!

[WDRacing]

HAhaha...could have sucked up a hamster....what a mess that would be.

[KATwo40]

Ok, I just checked all the pipes...free and clear. I can blow through the pipe at the throttlebody and feel it coming out the compressor inlet with my hand.

I did some MAF voltage testing at the ECU and here's what I found.

With the SAFC2 corrections set to 0, I got 0.53v @ the SAFC2 and 0.52v @ the ECU. I figure a .02v drop across the system is acceptable.

Here's what's interesting. With the SAFC2 dialed back to -28.8%, I get EXACTLY the same readings! Even though the engine isn't running, shouldn't there be a reduction in the voltage???

Here's what I think happened. I took the MAF sensor off today and smelled it (yep, that's certainly a professional and scientific test!). It had the distinct breath taking smell of burnt up electronics.

I think the MAF went bad, then maybe spike or short circuited or something and took out the SAFC2 MAF circuit.

Tomorrow, I'm picking up a chip burner and burning a new ROM for the 520cc/min injectors. I'll remove the SAFC2 from the picture and see what happens.

Heck, maybe the ECU is fried? Only one way to find out.

[WDRacing]

If that doesn't work....place #4 plug directly into the front of your pants, pour one cup of warm water over plug wire and pants, have a very good friend crank the motor.

Thats a for sure method to check for ignition!!!

WD

[KATwo40]

ROFL!

I know there's ignition...gave it the ol' ground it to the chassis and look for blue spark test. And, again, occasionally, it'll fire. It's just so freakin' rich it's insane.

[Florida240sx]

The % from the safc won't change unless there is airflow through the mafs....Put a fan in front of it My car reads .1% airflow with just power to it.