RobertISaar Posted October 18, 2010 Report Share Posted October 18, 2010 since pressure partly detemines flowrate, you would have to be running the same pressure at idle that the motor it came from to see similar flow at idle.... Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 18, 2010 Author Report Share Posted October 18, 2010 I ordered "26# Bosch 752" from ZZP, which would have corresponded I think to Bosch#0-280-155-752. With a known flow rate of 26# at our fuel pressure. They sent me Bosch#0-280-155-931... which maybe corresponds to the "28# Bosch 931" item also listed at ZZP. Although that does not make sense considering anywhere else on the internet that 931 part number corresponds to an injector that should flow 26# in my car. *shrugs* Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted October 18, 2010 Report Share Posted October 18, 2010 are they gray? Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 18, 2010 Author Report Share Posted October 18, 2010 Yeah... like a medium-dark gray. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted October 18, 2010 Report Share Posted October 18, 2010 both sets of mine are too. Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 18, 2010 Author Report Share Posted October 18, 2010 OK, so I got some sleep... so I can think better now. I'm at work, so I cannot get any data from the backup tune until this evening... but I want to try to understand the data I currently have. The INT of 76 is because the o2 is reading a way rich situation and the ECM is pulling fuel by seriously decreasing the Pulse Width to the crazy low 0.3ms that I'm seeing... and this reduced fuel is working because the BLM is at the ideal 128 and the car idles nicely. This seem right so far? What is tying my brain in knots... aside from why it needs to pull so much fuel in the first place if the injector size matches the tune... ...is how the INT can be *SO* low and the BLM still read dead perfect... and still have the o2 reading a slightly rich 706mV.... is this the car's way of saying "my shit's wack y0... but not so wack I can't adjust for it?" Also if it's running so crazy rich why is it not blowing black smoke during open loop? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 18, 2010 Report Share Posted October 18, 2010 the O2 COULD be dead and is giving false readings... wouldn't be the first time i've seen it happen. and the BLM SHOULD move towards where the INT sits at to transitition fuel from STFT to LTFT.... the fact that it's sitting perfectly still while the INT is sitting on it's minimum allowed value(i just checked the tune to confirm that) is odd... Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 18, 2010 Author Report Share Posted October 18, 2010 (edited) Well that explains why I'm so confused by these values... at least I'm looking at these numbers from the right direction. LOL I suppose to rule out a bunk o2 I'll pick up a new one on my way home (all I can get around here is Bosch, but I suppose a brand new Bosch is going to be more accurate than a potentially dead Denso)... then I'll get some revised fuel trim data from both tunes. Maybe that will narrow things down a little. *crosses fingers* Edited October 18, 2010 by Penglii Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 18, 2010 Author Report Share Posted October 18, 2010 Another random question: When I took those readings I had not yet performed a full idle relearn, since it takes *forever* with the colder T-stat. The ECM does not require the idle to be fully and properly re-learned before it will allow the BLM to move around in closed loop does it? I'd imagine it makes no difference other than idle speed & IAC position... and the IAC and Idle Speed both behaved fine without the full relearn. But I gotta ask... Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 18, 2010 Report Share Posted October 18, 2010 idle control and fueling control are largely seperate... maybe you hadn't hit BLM enable temps yet? Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 18, 2010 Author Report Share Posted October 18, 2010 idle control and fueling control are largely seperate... Thought so... maybe you hadn't hit BLM enable temps yet? Maybe. I thought that BLM enable temp would be the same as Closed-Loop enable temp... but perhaps not? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 18, 2010 Report Share Posted October 18, 2010 actually, BLM enable kicks on at 105*F coolant temps, while minimum closed loop coolant temps are 80*F... i think the reason it didn't move is due to pulse width... BPW must be higher than 1.09mSec in the current tunes to allow for BLM Learn at idle... that actually makes sense. Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 18, 2010 Author Report Share Posted October 18, 2010 (edited) Yeah, I don't remember exactly what the temp was... but I bet it was at least 105*F. That also makes sense about the BPW being way too low for the BLM to do anything... which further raises the question of why the pulse width is so low. Hmmm... think that's more evidence that the o2 might be junk? If it is, and it's bad readings were pulling the INT and the BPW down so far... then I'm surprised she idled so nicely rather than dying. Edited October 18, 2010 by Penglii Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 18, 2010 Report Share Posted October 18, 2010 your edit makes sense... unless the injectors are dumping in more fuel than any of us is realizing... the pulsewidths are probably somewhat normal looking right until it hits closed loop, then they shoot down into ranges that don't even make sense as the INT drops... Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 18, 2010 Author Report Share Posted October 18, 2010 the pulsewidths are probably somewhat normal looking right until it hits closed loop, then they shoot down into ranges that don't even make sense as the INT drops... Correct as usual King Friday... I wish I'd recorded what the BPW was during open loop, but obviousy both INT and BLM were 128 and whatever it was using for pulse width was not so rich as to cause lots of black smoke out the exhaust, as i'd imagine would happen if the injectors were flowing insane poundage... and as soon as closed loop was attained the pulse width started dropping like a rock along with the INT. Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 18, 2010 Author Report Share Posted October 18, 2010 BPW must be higher than 1.09mSec in the current tunes to allow for BLM Learn at idle... that actually makes sense. So... does this mean that the insanely low BPW numbers the Tech1 is showing me are probably just being ignored? Otherwise I'm not imagining how the engine could stay running with a pulse width of 0.3ms... the injector probably cannot even open/squirt/close in that time. If it's just ignoring the numbers because it's not enough to trigger the Block Learn ability... that would explain why there is no significant change in the idle quality between open and close loop even though the close loop numbers are in La-La land. I guess I'll find out soon since it's almost time to go home for the day. Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 19, 2010 Author Report Share Posted October 19, 2010 (edited) Curiouser and Curiouser... OK, new oxygen sensor... oxygen sensor is much more responsive, the values fluctuate more normally and realistically now. However, problem is not solved. If I just start the car and let it idle, I get the same behavior as yesterday... BLM of 128, INT drops to 76 and just sits there. Idle between 750 and 800. BPW still drops to an insane 0.3mV. Paying better attention now I can hear the engine struggling slightly even though the idle remains smooth. If I blip the throttle to like 1000RPM or more the Block Learn moves to Cell 1 and then goes back to Cell 0 while the revs drop back to regular idle. Blipping the throttle causes a hesitation at first until it's in Block 1... the engine struggles slightly more and the revs drop very slightly, and then go back up as it changes to Block 1 which causes the INT to reset to 128 and the BPW behave like normal. As the revs drop back down the Cell changes down to Cell 0 and the INT resets to 128 and the BPW will start out at normal for a moment and then rapidly march back down to 0.3mSec. Now when the INT floors 76 the BLM decreases by 1 like normal. Each time the BLM decreases, the BPW goes back up to 1.2 and then drops down to 0.6 while the INT pulls fuel away. With the main tune, the BLM settles down at 125 with an INT of 76 and a pulse width of 0.3mSec With the backup tune, the BLM settles down at 115 with an INT of 76 and a pulse width of 0.3mSec IAC is right around 30 When the engine idled long enough for the fan to come on (180* I think) it loaded the engine up slightly more and the BPW rose to like 0.4 or 0.6 or thereabouts. Blipping the throttle after the BLM settles will behave like the first blip but the BLM will never raise... just the INT will go back to 128, the BPW will seem OK, and then when it drops it settles back to it's apparently settled state. I have not tried to put her in gear or drive her around the block. Everything seems fine in Open Loop. No codes are being thrown. INT and BLM never try to go above 128. WTF is happening? :think::think::think: Edited October 19, 2010 by Penglii Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 19, 2010 Report Share Posted October 19, 2010 uber-richness is happening.... i have the alpha-N idle disabled since the latest TGP BINs from GM did, so all of the injector sizing is done via the BPC vs EGR table. now the factory table uses a value of 105, which corresponds to 3.1 liters with the TGP factory injectors. i changed the table to 89(18% less than 105) to have the ECM flow 18% less fuel to account for the change from ~22 lb/hr to ~26. now the BLM/INT with the main tune are showing that it's 21.5% rich without O2 correction, and on the backup, it's 25.4% too rich... it is hard to believe that these injectors can flow enough fuel in .3mS, even for idle... Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 19, 2010 Author Report Share Posted October 19, 2010 Holy balls! So basically these injectors are, for whatever reason, way larger than the 26# injectors I assumed I was ordering.... and the injectors they sent me are flowing like 31.5lbs?!!!?!?! This is certainly not a very driveable situation... I need to get some good known 26# injectors don't I? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 19, 2010 Report Share Posted October 19, 2010 well.... i could modify the tune to work with them.... quite a bit larger than necessary, but should you get into tuning yourself later on, or running code59 with a 3BAR MAP or something.... they could come in handy... or even E85... Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 19, 2010 Author Report Share Posted October 19, 2010 well.... i could modify the tune to work with them.... quite a bit larger than necessary, but should you get into tuning yourself later on, or running code59 with a 3BAR MAP or something.... they could come in handy... or even E85... Hmmm... I think that plan is WIN. I assume I should send you the chip? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 19, 2010 Report Share Posted October 19, 2010 yar, the modified MEMCAL... or just the EEPROM if you can pop it out without damaging it(i believe i put it in a DIP socket), ship it and stick it back in without bending/damaging pins... Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 19, 2010 Author Report Share Posted October 19, 2010 Rad, I will be sending it your way as soon as I can. I'll keep you posted. Quote Link to comment Share on other sites More sharing options...
Penglii Posted October 19, 2010 Author Report Share Posted October 19, 2010 Anybody have any idea why the GM#12561462 (stock Vette LS1/LS6 injectors) I received would be flowing so much more than their rated spec? I'm pretty sure my fuel pressure is stock... Not that it really matters why they are flowing so much... but I'm kinda curious. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 19, 2010 Report Share Posted October 19, 2010 just remembered: you have the modded G1, so i can actually mail you a spare EEPROM and you mail back the one you have in ATM when it gets there, that way if it needs to be driven, it's at least possible. Quote Link to comment Share on other sites More sharing options...
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