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Hello everyone a little new to the tuneing world. I tried using EEhack for the first time my 94 T/A LT1 be for that I used tuner cat. The problem I have I tweaked my injector pulse width alittle because of a cam swap so I loged the car made my change and re uploaded to the ECU now my LTrim left and right are locked at 128 am I missing something. Thanks for any information Gary
you definitely changed something else.
what emissions controls did you disable?
what xdf are you using?
there are various conditions that must be met for blm and cl to enable.
are either of the cl or blm indicators coming on in eehack? post your bin and/or log and ill have a look...
also welcome aboard
Hey Steve I love the program you made 100 times better that the one I use to start with. It is very possible I did do something or not did something right. I use Tunepro to log as you suggested. I will send you my log. If you don't mind looking at it that would be great. ill attach the bin if I can figure it out. Thanks Gary
No CL or BLM are not coming on all I changed was the injector plus width. But as with all new toys I was checking everything out and it is very possible I did do something. so I loaded the last tune back in with tunercat and still no Blm readings they were stuck at 128. I thought by putting the old tune bask in would fix it but it did not. Thanks Steveo
lets see a log?
it should go into closed loop if:
- the closed loop min. time has passed
- the o2s are 'ready'
- the coolant temperature threshold has passed
is it possible it's not getting hot enough?
this could be a coincidence unrelated to you changing bins...
I should be getting hot enough 163* it would switch before that before. I know its something I must of changed just cant put my finger on it ill post a run log I did the other day its about 4 minutes long just to warm it up. Just tried to upload the eedata file it wont let me. Any other way to get it to you ? Sorry Steve just not use to uploading on forums or just not very good at it lol thanks again Gary
you can upload a .zip file i think just try zipping it.
zipping the log and the bin you were running at the time would be good practice for getting help on a forum like this...
hope this works lol. Thanks a lot Steveo for taking the time out of your day to help someone new to the tuning world.......Thanks Gary
no problem, i'll try to have a look at it tonight when im back at home.
Thanks much appreciated
seems a lot has been changed in that bin but i don't see anything specifically that should prevent closed loop.
take a datalog with eehack and post that
Wasn't the one I sent you a running Eehack log ?
here is a the eehack run data log
your o2 sensors are not doing well. they are both parked at 450mv from cold start.
open the graph window and select 'left oxygen sensor volts' and 'right oxygen sensor volts'.
a healthy o2 will start at high voltage (900+mv) and as the exhaust temperature rises, start to dip a bit. then the car goes into closed loop.
your o2s are never 'becoming ready'.
see attached graph
Wow didn't pay no attention to that they look like they are dead. I will have to check wiring. Maybe dead o2. That could be the reason it won't go in to close loop and are stuck at 128 BLMs ? Thanks Steveo I'll go take look and see what I find I'll let you know
it's definititely the reason, i've checked your bin over several times and every other condition in your log seems to be met.
Just checked o2 wire voltage that fine. The o2 test dead so I have to get a new set. If they were bad would it lock at 128 it should make BLMs higher or lower correct ?
your blms are intialized at (by default) 128 then they're 'trimmed' based on measurements from closed loop, so if it's not going into closed loop, it'll be locked at 128.
your ecm is smart enough to know that an o2 stuck at 450mv can't be reading correctly yet, so it's not entering closed loop. if you drove around for long enough, it would certainly set an o2 error code or something...
That makes perfect sense Steve. I have not driven it it's winter here I just put in a new cam and was just going to tune it at idel till I can get it out on the road. I'm running stock o2 for not till I get the fueling better then switch to wide band o2s and find tune it. I will let you know if the o2 fix it. Thanks so much for the help. That's very nice and informative Gary
no problemo.
just fyi you can tune it very well using narrowbands with eehack's analyzer
you really just need wideband to tune wide open throttle
I will give it a shot. Your program has so much to offer can't wait till I can use all the awesome features it has to offer. I may need some help understanding some of it at some point. Lol Thanks again steveo :)
Hey steveo got the new AC Delco o2s in BLMs are now active. One question is the don't seam to heat up very good with key on I checked for 12v to the o2 and it's present. Pull o2s back out to ohm the heater it reads 14 ohms on both should be only 5 to 7 ohms correct ?. Also I should not have constant 12v to heaters from what my manual tells me. 12v should only last 2 seconds from what the book tells me. It uses the AC relay for power for 2 seconds and deverts power back the AC compressor witch the AC system is deleted. Thanks Gary
im almost certain this is incorrect. i've never had an LT1 wired like that. the heaters should be powered from ignition power as far as i know, and always be on.Quote:
It uses the AC relay for power for 2 seconds and deverts power back the AC compressor witch the AC system is deleted. Thanks Gary
don't worry too much about the heaters, if it gets warm in open air with the key on, it's fine. i've run without heated o2s too, just turned the closed loop timer way up so it had enough time to get hot from exhaust heat.
I don't believe they are getting hot enough it does go in to close loop but the milavots are real low more do on the left side it stays around 200 to 250 when running for about 10 to 15 minutes. So it's giving me split blms
Decided to go back to the basics fuel and spark. Pulled wires and OHMd them out at 200k on the meter #1 was 01.8 #3 02.1 #5 02.5 #7 was 55.9 way off from the rest pulled that plug it was black and wet so I need a new set of wires what kind do you recommend ? I'm guessing but it not firing would make the exhaust cooler on that side
stock AC delco wires are fairly high quality, but with headers you might want a cut-to-fit set (msd makes one)Quote:
I need a new set of wires what kind do you recommend
closed loop hates dead cylinders. a non-firing cylinder pumps air, so that bank would probably read lean to an o2 sensor, which would typically make closed loop enrichen the other cylinders, so you have three rich cylinders and a dead one....Quote:
I'm guessing but it not firing would make the exhaust cooler on that side
I'll have to order the MSD cut to fit ones. I too think they would be better so I can route them away from the headers. I'll also get a new set of NGK plugs also. Thanks again for the help and information
Hey Steve got my new wires and plugs it fixed the split in my blms. Now both side are running at 160 witch is way high and the same with the INT both are at 193. The o2s look to be switching fine I tried to increase that map table at ideal but no luck. Any ideas what to look for or try ? Thanks Gary
160 is max (in a stock bin) so that means closed loop is giving up.
with your BLM and INT both maxed out, it's practically impossible that your O2s are switching properly. normally switching o2s are a result of closed loop operating properly, and closed loop really can't operate at its maximum trim thresholds
with trims like that i'd either expect a constant to be way out (injector size or something), a severely misfiring cylinder or two, big vacuum leak, something like that.
show us another log?
i have uploaded a zip file with the tune and the newest log. i will look to make sure the wires are rite but it don't seam to have miss and revs good. i looked at any vac hoses and tested for vac leaks all looks good. I did notice that if i increase the rpms the blms will drop don't know if that means anything or not was just a observation. There are some differences in tune bin constants than what information i have like cylinder vol. inj. pulse width ect. i can send any information to you if you would like (mods parts ect). I'm at a loss been trying to figure it out for the last year and had no progress. i'm just glad i was able to find your program and yourself to take the time to help. Thanks again Steve
your log is only 7 minutes of non-moving idle, that won't do much good to actual tuning (unless all you want to tune is hot idle)
what 160 BLM means is that the computer is trying to add more fuel, and it has to dump so much fuel (at least 25% more) that it gives up. this is because it's interpreting your very low o2 voltage as 'lean'.
run my 'cl performance' analyzer:
your O2 sensors never exceed 700mv and are only generating 136 cross counts for 3100+ events. this isn't normal.
either you have a massive vacuum leak at idle, a massive exhaust leak, you need more idle fuel (maybe a constant is way out), or your o2s are not behaving correctly.
i looked at your bin, are you actually running 37lb injectors? i also think your cylinder volume constant is a bit high, i usually use ~7.85-7.90 for a 383 and you have 7.97.
i might try just lowering your injector constant slightly until it doesn't peg BLMs at 160, then you can log and tune from there?
I have 36# injectors the spec sheet calls for 37.12 at 43.5 fuel pressure. I can not hear any exhaust leaks. I will get out the fog machine and fog the intake and exhaust. I will change what you recommended and see what happens. Thanks a bunch Steve I will let you know the out come
another approach is investigating by feel
does it run better, or worse with the 160 trims?
if you go to eehack's parameter control page and RESET BLMs (so it runs just fueling tables without the o2s acting out), does it get smoother or rougher?
how about if you check 'override afr' and lower the slider (adding more fuel. this keeps it out of closed loop). you can try 'expert mode' in that same screen to get more extreme AFRs.
you could also try skewing spark advance down and see if less timing advance gives you a smoother or rougher idle
the results from that kinda stuff will give you more clues
Thanks for the information I will do that testing to. Thanks alot for all the help Steve
Changed all that you recommended. Depending on what constant was changed the high BLM will go from side to side while the other will drop to 128. I did see that the driver side o2 has very low cross counts. So what that tells me is that o2 is not switching back and forth. I got a new set to replace the new ones I already had. What do you think would make the low cross counts ? Bad signal wire ? From computer
tried to upload a mod list wont let me it tells me the web page is not working ill try again later. Thanks Steve
got it to load had to put it in a zip file. Any questions on the mods just let me know. Thanks
LT1 388 forged rotating assembly
Spayed main bearing caps
Bore: 4.060
Stroke: 3.750
Rod Length 5.700
Hellfire rings
Trickflow Aluminum heads
62cc Combustion Chamber
2.02in./1.60exh.
.600 lift springs
1.5 Roller rockers
Comp R lifters
Chromoly push rods
Lunati VooDoo 60123 cam
Duration: .294int./.302exh
Duration @ .050: .243int./.251exh
Gross valve lift: .560int./.565exh.
LAS: 110
36 lb. Accel injectors
14.4 ohms
Actual flow rate @ 43.5 (37.12)
High vol oil pump
Racetronics 255 high vol. fuel pump with hot wire kit
58mm BBK Throttle body
IAC drill mod
Pro M 3AL75 MAF meter
MSD coil
MSD Opti spark
MSD 8.5 Wires
Moroso CAI
TB coolant bypass
Long tube Pacesetter headers