|
Home | Rules & Guidelines | Register | Member Rides | FAQ | Members List | Social Groups | Calendar | Mark Forums Read |
S Chassis Technical discussion related to the S Chassis such as the S12, S13, S14, and S15. |
|
Thread Tools | Display Modes |
|
02-05-2015, 04:22 PM | #1 |
Zilvia Member
|
Extremely Lean After Enthalpy ECU Install
Hey guys, been in talks with Martin over at Enthalpy but thought I'd turn to the forums for some insight. My current setup is as follows:
T3/T4 Turbo 370cc Injectors (stock SR) Z32 MAF Walbro 255 Stock Internals ECU is tuned for T25/28, 370's, Z32 MAF, 91 octane After installing and wiring up the new ECU and MAF car starts but runs completely rich on the AFR... Not sure if these ECUs run on an open or closed loop? Also, if have a faulty knock sensor (code) would cause it to pull the timing enough to run completely lean like this? Here is a video of current running conditions:https://www.youtube.com/watch?v=Aqt1...ature=youtu.be |
Sponsored Links |
02-05-2015, 04:48 PM | #4 |
Post Whore!
Join Date: Mar 2008
Location: San Diego, CA
Posts: 4,140
Trader Rating: (27)
Feedback Score: 27 reviews
|
The knock sensor will not change your fuel maps at all. It's really there to tell if there's crappy gas in the tank and will pull timing under light/no load if it senses knock if I remember correctly.
I'd check if your injectors are leaking past the orings. If they aren't I'd then check the maf. |
02-05-2015, 04:52 PM | #5 | |
Zilvia Member
|
Quote:
|
|
02-06-2015, 06:17 AM | #6 | |
Nissanaholic!
Join Date: Aug 2011
Location: France - Toulouse
Age: 41
Posts: 1,851
Trader Rating: (0)
Feedback Score: 0 reviews
|
First, get a new knock sensor. I could not hear sound on the video, but starting that lean and keeping that lean could be anything fuel / air metering related. So ...bad fuel delivery (pump/injectors/filter/FPR), bad air metering (faulty MAF, boost leak, leaking BOV), or bad mapping.
I'd try with a known working z32 maf, too. If you know someone with a scope, have him analyze the maf response, i am quite sure you got a chinese copy and these are known to have a very poor, unfiltered response. Quote:
When the ECU detects knock, it pulls timing AND uses the alternate fuel map and timing map. If injectors were leaking, he would have hydrolocked his cylinders too. |
|
02-06-2015, 11:15 AM | #7 | |
Post Whore!
Join Date: Mar 2008
Location: San Diego, CA
Posts: 4,140
Trader Rating: (27)
Feedback Score: 27 reviews
|
Quote:
^this is from the full service manual by the way. No where does it say that it will change the fuel map or affect anything under normal driving conditions for that matter. It merely pulls timing when it detects knock when the car is NOT in normal driving conditions(aka light/no load), which is what I stated earlier. And the orings can leak a little or a lot. There are confirmed cases in which an oring is slightly damaged and leaking enough to cause a rich condition. Hydrolock is more common in cases where the intake pipe sucks up a bunch of water when the car drives through a puddle. I'd say that's unlikey here considering that would be some extreme fuel leakage. |
|
05-13-2015, 09:48 AM | #8 | |
Nissanaholic!
Join Date: Aug 2011
Location: France - Toulouse
Age: 41
Posts: 1,851
Trader Rating: (0)
Feedback Score: 0 reviews
|
Quote:
Ask any tuner using a nistune, and he will tell you are wrong. The ECU has 2 sets of fuel & timing maps, when it detects knock it uses the alternate knock maps (and may pull timing on top of that, many users reported this when copying normal maps to knock maps). Or you could just seach the internet for the ECU address file. You will see there are 2 sets of maps. If you are still not convinced, reverse engineer the ecu code. It is an old and simple mcu, so while tedious, it still is easy. Anyway, mail order tune have their limits and injector modification is not that easy, esp. with a different FPR. Either your injectors are actually bigger than you think, and have a shorter latency than what is in the tune, or you may have a problem with the FPR, or ... the mail order tune is actually very rich on purpose, as no one wants a blown engine because the fuel system is weak. It is not hard nor to set latency and K correctly, but the tuner really needs the car to get it spot on. It cannot be done without. |
|
05-13-2015, 03:45 PM | #9 | |
Post Whore!
Join Date: Mar 2008
Location: San Diego, CA
Posts: 4,140
Trader Rating: (27)
Feedback Score: 27 reviews
|
OP what do you mean Enthalpy "erased the code"? Couldn't that have been achieved with an OBD scanner or simply disconnecting the battery? Or did he disable the knock sensor circuit? curious..
Quote:
I'm not completely ruling out the possibility that Nissan designed the stock ecu's with two fuel/timing maps, but I just have a hard time believing that they wouldn't have mentioned it in the FSM. Case in fact: My engine was producing devastating knock on boost which ended up cracking ring lands on #4 and there was no apparent change in the driveability. Even JimWolf himself told me that the knock sensor is there to retard timing under light loads and was mostly used to "protect" (although very minimal) the engine from bad gas, etc. |
|
02-05-2015, 04:58 PM | #10 |
Leaky Injector
|
- do you have a good walbro?
- what's your fuel pressure? - OEM JECS Z32 / N62 MAF? - do you have any funky rev cuts? (faulty maf or maf wiring) - did you follow the JWT wiring diagram? It's backwards from what it looks like btw. - you haven't retimed the car at all? - where did you get the SR injectors? (I always opt for buying new fiveO injectors, as they use denso blanks, / they do not redrill injectors, and they flow test with heptane at specific pressure and give you flow sheets. New injectors is just nice so you don't have to worry. Redrills are a bad idea. The tunes enthalpy sends are usually 99% spot on. My car is close to 600whp, and the tune didn't really need to be tweeked on the dyno. And my setup is far from stock. Most of the tunes he sends are actually dynotunes from other cars with the same setup (they've tuned thousands of cars,... literally) . |
02-05-2015, 05:03 PM | #11 | |
Zilvia Member
|
Quote:
|
|
02-05-2015, 05:42 PM | #13 |
Zilvia Member
|
|
02-17-2015, 07:59 PM | #18 | |
Nissanaholic!
|
Quote:
Ah, and this is straight from Nistune's web page, #2 clearly states not to use fake mafs: |
|
02-06-2015, 11:19 AM | #19 |
Leaky Injector
|
If you have a leak after the MAF (turbo, chargepiping, intercooler, bov, manifold etc.)
in vacuum the engine is sucking in air that isn't metered by the MAF. Therefor the ECU doesn't know about some of the air going in, so it creates a lean condition. This is reversed when there is positive pressure as there is metered air leaking OUT of the system. That makes it so the ECU is putting fuel in for air that's not there. ISIS MAF should be ok. Hell we dynotuned a stock S13 SR with an "ONLYMAF" ebay maf (haha I cautioned him against it). But Martin dynotuned it and got 258whp out of a t25 370cc setup. Then after it we got 255whp out of another stock SR using a JECS OEM N62 MAF. (obviously the MAF didn't make the power difference, it is simply showing that both mafs did the job). The hot wire element in the ebay MAF was a weird coiled spring instead of the antenna looking element of JECS. Realize a hotwire maf is simply a wire that is heated by the system to create resistance. So your 5V signal through the MAF is resisted down to .45V or so, and as air flows through it it cools the wire, reducing resistance and increasing voltage. This works realyl well as it accoutns for temperature and air density changes and can accurately meter air MASS instead of using a calculation. This is why OEMs use MAF instead of MAP on turbo application. -how sure are you on those injectors? (can you try known good sr 370cc injectors from a running stock SR?) - boost leak test - test fuel pressure |
02-07-2015, 12:14 PM | #20 | |
Zilvia Member
|
Quote:
- Will also test for boost leaks, but not sure how that would cause me to run lean - Installing a fuel pressure gauge most likely tomorrow to see how the fuel pressure is |
|
02-14-2015, 01:33 PM | #21 |
Zilvia Member
|
Sent ECU to Enthalpy.... Turns out ECU was tuned for N60 not Z32 as advertised by the guy who sold me the ECU.... Problem solved... Shout out to Martin at Enthalpy for always being extremely helpful.
|
03-01-2015, 01:44 PM | #22 |
Zilvia Member
|
UPDATE: So, after having the ECU retuned and getting bigger injectors, now once installed it is running very rich... 12.3-12.6 at idle and 10.0 while driving... I can get it into boost but bogs heavily and doesn't pull at all.
Any ideas? Not running a boost controller, just the 7lb spring in the external TiAL 38mm wastegate... Ideas? |
05-13-2015, 08:00 AM | #25 |
Super Moderator
Join Date: Jun 2004
Location: SF Bay Area
Posts: 16,761
Trader Rating: (73)
Feedback Score: 73 reviews
|
Are you still running that Isis maf? Try getting an OEM used one.
For the record my enthalpy tune runs about the same as yours. Idles around 11-12.5 cruises anything over 10% throttle at 10 AFR. Sucks.
__________________
Best way to do business with me? Make your best offer FIRST. |
05-13-2015, 08:12 AM | #26 |
Zilvia Junkie
|
Then you have something wrong with your setup, not the tune.
|
05-13-2015, 03:01 PM | #27 |
Zilvia Member
|
UPDATE: Turns out I had a knock sensor code, and I sent back to Enthalpy to have the code erased, got the ECU back and runs much better now, its actually drivable now, but I may get an SAFC II to fine tune.
Big thanks to Martin at Enthalpy for being extremely helpful and handling all of my questions in a timely and thorough manner. |
05-15-2015, 02:38 AM | #28 | ||
Nissanaholic!
Join Date: Aug 2011
Location: France - Toulouse
Age: 41
Posts: 1,851
Trader Rating: (0)
Feedback Score: 0 reviews
|
Quote:
Tried it on a toyota ecu but it didn't work ( the work differently, it is a pain) Quote:
The FSM is a manual for stores, not for reverse engineering enthusiasts, that is why the info is not in. I believe nistune makes a demo version of its software, it is very crippled and unusable to tune, but you can test the UI on it and see for yourself. You can also check the address files, they are provided in the "rom pack" . You will see there is a knock fuel map and a knock timing map. If it sill is not enough, i think i have the code somewhere for a ca18det (lower level is different from sr20 but it works the same way. It is also easier to understand as it actually was written in asm on the first versions, not compiled as it is on the 44F ECUs). It is a 6802 MCU, which is a very old and simple µcontroler, so it has very few instructions. Seriously don't do that. It is the nastiest piece of crap you can fit on a MAF system. I don't understand why so many people want one. That thing changes the MAF signal, and your ECU relies on this to set fuel AND timing . Tuning the K and latency values is a 30mn work, and it does not requires a dyno, just a wideband AFR sensor. |
||
05-15-2015, 12:10 PM | #29 | |
Post Whore!
Join Date: Sep 2005
Location: SWFL
Age: 47
Posts: 3,318
Trader Rating: (3)
Feedback Score: 3 reviews
|
Quote:
Tuning the k and latency is easy, but that's not where the power comes from. I can confirm that an un-tuned Sr can make 350hp from a 2871r @ 17psi with just a mafs and an injector upgrade. Still people are like, this tuner tuned my blah blah and I make 350hp at 20psi. And yes I've tweaked a few of enthalpy tunes, they are usually conservative from my experience and can benefit from dyno time if you want more power. Not everyone needs more power or to conserve gas though, so if you just need your engine to run correctly you're good to go! Sent from my Highly Tuned Note 4.5!!!
__________________
LoverTechnologies "Half Broken Things!" |
|
05-13-2015, 04:22 PM | #30 |
Nissanaholic!
|
Prob disabled the knock sensor. After changing 4 knock sensors and 3 sub harnesses I told martin to just rid me of that shit. Had no issues for a year, then he came and tuned me on the dyno without it.
__________________
MRP Manufacturing |
Bookmarks |
Thread Tools | |
Display Modes | |
|
|