RTEK 1.8, 4 x 750cc injectors, Apexi Neo MAXED - STILL LEAN UNDER WOT
05-05-12, 01:01 PM
#28
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the filter before the pump could easily be the problem, but if its not try "T" ing the boost gauge into the fuel pressure regulator hose, the n00b mistake with a T2 is just to assume every nipple in the intake sees vacuum AND boost, and they do not. there is a port there that is ONLY vacuum, so you end up really lean in boost.
05-05-12, 01:16 PM
#29
the filter before the pump could easily be the problem, but if its not try "T" ing the boost gauge into the fuel pressure regulator hose, the n00b mistake with a T2 is just to assume every nipple in the intake sees vacuum AND boost, and they do not. there is a port there that is ONLY vacuum, so you end up really lean in boost.
05-05-12, 01:41 PM
#30
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Your point is well taken... BUT, i'm running my vacuum source directly off the s5 LIM.. Inside face.. Half way up runners.. That single nipple between and a little lower than the injector bosses.. The one that angles towards the rear of the engine.. THAT should be a direct port and i've veritfied it see's a strong vacuum idling... Have't check if it see's boost but will look into that after i swap my filter setup.
05-06-12, 08:15 PM
#31
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I would like to point that your large streetport would not in any way help you use that much fuel. Personally i would be running an aftermarket FPR as soon as I changed injectors. It is a fuel pressure problem whether it is from the filter or the regulator. Either that or your wideband sensor is completely fucked.
If your still waiting for that filter why not just try bypass it for the purpose of the test.
If your still waiting for that filter why not just try bypass it for the purpose of the test.
05-08-12, 02:23 PM
#39
Is this an issue that suddenly developed or are you still troubleshooting the initial swap?
Does it go lean under 3500 rpm, over 3500 rpm, or always?
I still suspect the secondary injector wiring. With the key on, ground out the signal wire at the ecu and listen for the injector to click.
Walbro's are rated at 12v anyway, so 11.5 vs 12 probably isn't going to change much. If the voltage drops a lot under load, then that's a different story.
You should have higher than stock fuel pressure with a stock regulator and walbro 255. So another FPR is going to be a band-aid, at best.
I remember someone mentioning about the S5 ecu needs the fuel pressure regulator solenoid plugged in, even if it is not attached to anything else. I know you said full S5 swap, but do you have your full solenoid rack attached?
Does it go lean under 3500 rpm, over 3500 rpm, or always?
I still suspect the secondary injector wiring. With the key on, ground out the signal wire at the ecu and listen for the injector to click.
Walbro's are rated at 12v anyway, so 11.5 vs 12 probably isn't going to change much. If the voltage drops a lot under load, then that's a different story.
You should have higher than stock fuel pressure with a stock regulator and walbro 255. So another FPR is going to be a band-aid, at best.
I remember someone mentioning about the S5 ecu needs the fuel pressure regulator solenoid plugged in, even if it is not attached to anything else. I know you said full S5 swap, but do you have your full solenoid rack attached?
05-08-12, 05:59 PM
#40
This is initial troubleshooting with new engine... Just finished breakin miles...
I occassionally get a little stumble when the secondaries kick in around mid-3k rpm range, so, i'm fairly certain they are working... I don't go WOT under 4000 rpm
I occassionally get a little stumble when the secondaries kick in around mid-3k rpm range, so, i'm fairly certain they are working... I don't go WOT under 4000 rpm
05-08-12, 07:13 PM
#41
Here's my crazy theory: Running 3 injectors with a MAF signal modified by 50% may be able to keep your AFR's near your target. Once the MAF opens more than 66% (+50% from the SAFC) the ecu reads 100%. The SAFC can't modify the signal beyond 100% and the 3 injectors can't keep up. (See, Math can be useful!
)Homework for you in order from easiest to most likely to require the fire department:
Check secondary injector wiring, or all of them since you're in there
Confirm boost coming from nipple feeding the fuel pressure regulator
Fuel pump voltage under boost
AFM output checks out according to the FSM
Fuel pressure under boost
05-08-12, 10:34 PM
#42
Well.. I suspect my secondaries.. Did a pull starting at 3k rpm with low-11s afr... Right at about 3600 rpm it starts going lean... U can just watch to numbers climp past 12.5
So, i guess i need to check my secondaries wiring as I know the injectors themselves are golden... Ignition on > gound out secondary signal wires a ECU > listen for injector "CLICK"?? .. Or do i supply 12v?
So, i guess i need to check my secondaries wiring as I know the injectors themselves are golden... Ignition on > gound out secondary signal wires a ECU > listen for injector "CLICK"?? .. Or do i supply 12v?
05-09-12, 10:31 AM
#43
Well.. I suspect my secondaries.. Did a pull starting at 3k rpm with low-11s afr... Right at about 3600 rpm it starts going lean... U can just watch to numbers climp past 12.5
So, i guess i need to check my secondaries wiring as I know the injectors themselves are golden... Ignition on > gound out secondary signal wires a ECU > listen for injector "CLICK"?? .. Or do i supply 12v?
So, i guess i need to check my secondaries wiring as I know the injectors themselves are golden... Ignition on > gound out secondary signal wires a ECU > listen for injector "CLICK"?? .. Or do i supply 12v?
05-09-12, 10:49 AM
#44
Your not listening to anything that knowledgeable members are suggesting. Your just gonna end up chasing your tail around. Have you changed the filter yet? Make sure you have a proper high flow EFI fuel filter. Also I would look into upgrading to a 2nd gen sending unit and fuel pump. I've seen threads on putting them in 1st gen tanks. But the GSL-SE tank is the best because it has a baffle to prevent the fuel pump from starving.
First thing I would do is check fuel pressure, make sure the pressure raises accordingly with RPM. If your injectors were recently cleaned/serviced I doubt they shorted out so quickly, unless they're really cheap quality.
And as people have suggested, I would upgrade to an aftermarket fuel pressure regulator to support your upgraded fuel injectors. Preferably one with a gauge like an Aeromotive unit.
First thing I would do is check fuel pressure, make sure the pressure raises accordingly with RPM. If your injectors were recently cleaned/serviced I doubt they shorted out so quickly, unless they're really cheap quality.
And as people have suggested, I would upgrade to an aftermarket fuel pressure regulator to support your upgraded fuel injectors. Preferably one with a gauge like an Aeromotive unit.
05-09-12, 12:04 PM
#45
I'll check for "click" this afternoon by grounding injector signal wires at ECU w/ ignition on. I just want to rule that out before i start "chasing my tail"... I even left Rx7 at home so i'm not working over hot engine this afternoon... I should be able to get right on it after work.
Same wiring harness -> previous engine died from front apex seal failure... REALLY curious about front secondary injector activation... Will let you know
Same wiring harness -> previous engine died from front apex seal failure... REALLY curious about front secondary injector activation... Will let you know
05-09-12, 07:32 PM
#46
Tested all injectors at ECU with key on... All same voltage... Primary Injector Dynamic (modified Bosch) injectors make loud "click" when grounded that i could easily hear while probing the ECU... Secondary RC injectors make much quieter "click" that i had to run a jumper wire under the hood from the ECU to hear the injectors while grounding.
So.... Yeah.
.... I guess i need to fake a load now, rev to 4k rpm while probing the ECU and look for a voltage drop in the secondaries with my DVM??? *Confirm signal leaving ECU to fire them? *Or, how do i do that?*
So.... Yeah.
.... I guess i need to fake a load now, rev to 4k rpm while probing the ECU and look for a voltage drop in the secondaries with my DVM??? *Confirm signal leaving ECU to fire them? *Or, how do i do that?*
05-09-12, 07:41 PM
#47
... Is my wideband dieing? I have an AEM UEGO wideband.. It does NOT preheat i've notived and rarely reads FULL lean when decelling... THESE NUMBERS ARE ONLY WHILE DECELLING... Will read mid to high 16s until it warms up (five minutes maybe) than will usually read 17.7-18.0 until it gets REALLY warmed up (hard driving) when it will read --- (full lean)... Prob just need replacement o2 sensor? I really doubt the controller went bad
05-09-12, 07:45 PM
#48
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... Is my wideband dieing? I have an AEM UEGO wideband.. It does NOT preheat i've notived and rarely reads FULL lean when decelling... THESE NUMBERS ARE ONLY WHILE DECELLING... Will read mid to high 16s until it warms up (five minutes maybe) than will usually read 17.7-18.0 until it gets REALLY warmed up (hard driving) when it will read --- (full lean)... Prob just need replacement o2 sensor? I really doubt the controller went bad
did you try the vacuum hose yet? it'll take you 5 minutes.
www.foxed.ca has the S5 training book, it does mention when the secondaries come on.
05-09-12, 07:55 PM
#49
.. I have an old Sun dwell tach i could wire into secondary injector wires... It would output in a 0-90 scale (which can closely represent duty cycle)... Hmmm
Here's how you do it...*http://www.gassavers.org/showthread.php?t=7714
Here's how you do it...*http://www.gassavers.org/showthread.php?t=7714
