Hello, Im just trying to catch up here. Your last log looked nice and steady as far as idle speed goes so what is it doing or not doing that you do not like exactly?
Hello, Im just trying to catch up here. Your last log looked nice and steady as far as idle speed goes so what is it doing or not doing that you do not like exactly?
1.) Terrible lean condition when I start it up regardless of temp. Sometimes it starts where it should at 14.7 but after a few seconds it goes up to 19+. Sometimes it just goes straight to 20:1 and wont come down until you go for a drive. Sometimes it does by its self just idling. Seems to be worse after a reflash. Its driving me fuckin nuts cause nothing seems to help. And adding to the VE just makes it way richer than target when it finally does come down.
2.) Reflashing the car causes sensors to read incorrectly for some reason. Turning the car off, cycling the key a few times, and then starting it up seems to mitigate that but not always.
3.) Idle sounds really muffled for some reason and only seems to go away if im up around 24 degrees of idle timing but as Hondaeater pointed out my logs show that its too high. Increasing the idle spark seems to give less MAP when it should be the other way around. But if I set base timing lower than 20 or so it sounds really really muffled. Almost like its drowning.
I believe the lean condition is possibly the worst one. Starting to think my ECU is crapping out or something because when I last tuned the car it had none of these stupid issues nor did they exist when I first started the car up after the swap. What im going to try on sunday is to replaced the header gaskets and double them up since they seem to keep blowing. I got a stud kit to hopefully help with clamp force. I believe I remember I had a very similar issue to this before (not this bad though) when I had a blown header gasket on the driver side. My wideband sensor is on the driver side header so it makes sense. Kinda. Im going to also replace the intake manifold gaskets too just in case its losing vacuum through there or something.
Heres a log at 18 degrees idle timing. Seems like everything is working correctly but the exhaust sounds muffled almost as if it were under water or something. I can record a sound clip and upload it if youd like so you can see what I mean about the exhaust note. Let me know if you see anything I dont.
have not had time to look at your logs. Is idle AND light throttle driving lean?
Is it just your warm up cold start that is lean? I thought I suggested you set 1.25 in OL table -40deg from 0 down to 100 kPa and then interpolate all the way to 140deg? If you did go ahead and set 1.25 from -40 to the 1st positive ECT degree in the table, I'm not at my computer so I don't know what that is, anyway from +ECT to 198 degrees, interpolate. Because you never go into CL, you're going to need to do a better job of dialing in your open loop table for cold start. Keep increasing the fuel/air ratio in that table until you get your desired warm up richened up. Be very aggressive here it's easier to take some back out once you've gone in the rich direction. If it's lean at idle you have to be careful.... that's a big cam and it give you a false reading but you should recognize that as soon as you start driving if it's still too lean at that light throttle high vacuum below 3000 RPM then you don't fix it in this table and you don't fix it from the ve table. Let's figure out which of these scenarios is the problem before we go adjusting more than just your warm-up table.
ok so first thing about the idle afr, I honestly would only worry about if under certain conditions. Conditions to care about idle afr are contingent on whether or not you know for certain that a) you do not have an exhaust leak of any kind. b) you have at least 24" of exhaust tubing behind the o2 sensor. If those two are satisfied then I would watch if a) I had a hard start condition either cold or hot or both. b) had poor throttle response c) had poor idle recovery after a rev. d) Bad idle quality. If your satisfied with all 4 conditions then idle afr really isn't worth stressing over.
Now for the idle muffled sound, Im not understanding the condition. I don't think he way you described it is the problem either. The reason I am having trouble is that my experience is the opposite. Whenever I decreased idle timing, via the overspeed control, down closer to zero I have a very loud and choppy idle. This same sound can be had by running a lean idle afr or a combination of the two. When ever I leave the idle speed via spark controls alone or reduced so that idle timing is around 20 or so degrees steady, I get a quieter and more subdued idle sound. record the sound with narrative and data log to go with it please.
I replaced both header gaskets and doubled them up with GM steel gaskets. Both sides had one blown header pipe for sure and a couple others but less severe. Hopefully they dont leak again because holy shit installing them SUCKED ASS. Theres no room at all but its done and over and im trying to forget about that trauma. Since I now know the headers were leaking, ill have to readjust my VE but thats not a big deal. Onto the results;
I started the car up with 20 deg base timing. Surprisingly it started up rich around 13:1 and within a few seconds went up to 14.7. It seemed to hold it there for a little bit but then started to go rich up to 18:1. Not as bad as before but still not ideal. It did start to come down much quicker so at least I know my pain and suffering made a difference. Oddly though my IAC counts were up in the 200s. Not low 200s but mid 200s. I thought it was weird because I know my IAC counts should be between 40-50 when tps is at .25 v. Fully warmed up IAC counts were in the 160s. Super odd. You can see in the log when I start to increase the set screw to open the TB more until the tps % got too high to stay in idle spark. So I shut it off, figured if its in the 160s it must need a couple turns. To my surprise, after doing a tps reset, I started the car back up and my IACs were 0 *facepalm*. So I close it down and sure enough, tps voltage was .25 v to get 40-50 IAC counts which is what I had it at before. In the longer log, you can see a spike in timing when my IAC went from 180s to 140s instantly. Luckily my spark control is pretty aggressive and prevented a stall. Based on that I think ill figure out what spark advance gets me MBT. I failed to look at my wideband when I did a hot start since I was messing with my set screw. Id like to think that it must have been near stoich because if it had been near 18-19:1 it would have been significantly more choppy and it wasnt. Ill have a better look tomorrow and maybe figure out how to get it logging on my gaming laptop so you can see the AFRs.
I realized after some searching that I thought a higher MAP means more vacuum which now I know is the opposite. Timing here was set at 20 but like I said ill increase it until I get the lowest MAP possible and then turn it down a few degrees to allow some headroom in case of a stall condition like in the first log. I unfortunately cannot get HP Tuners to read my got damn wideband now so im going to try and find a Windows 10 copy to load onto my laptop. I think windows 11 is giving me issues because it reads perfectly without delay on my old gaming laptop. I cant use it to tune though because the battery will die if not plugged for longer than 20 minutes.
Hondaeater: Its not VE related I know that. It seems to only be an issue during start up. Once you go for a drive it goes away completely. Now that I have fixed my exhaust leaks I may play around with the ECT Fuel Adder until I get my O2 sensors working again. I did do the OL table like you specified. But like I stated earlier it goes away so this table isnt the culprit. It has to be something else and im leaning more towards the ECT Adder now that my exhaust leaks are fixed (prewideband anyways).
Reubone: Ill try and get a sound clip of it tomorrow so you can see what im talking about. I did notice it goes away with very low idle timing but now that I realize I need more vacuum to stabilize the cam, decreasing it would make it worse. Ill play around with idle tomorrow when I have more time. I finished super late today and couldnt idle my car much.
Thanks for your help guys I appreciate it.
Lol. If you are lean while it warms up you need to add 10-15 percent to the OL table until it becomes rich as it warms up.
When you 1st crank it you are using the FA1 table for cranking fuel then it transitions into OL table quickly.
OL table controls the warm up fuel, parked, idle. Idle spark can help but you realize everytime you change timing your adjusting the amount of air flow needed too? Raise spark needs less air and now you have to go back and adjust the iac and TPS. Lol. 18-20 deg leave it alone, set the IAC. If you reach about 1.7% throttle opening you need to do a TPS reset.
To perform that... key off, unplug both IAC and TPS. Turn Key on do not start WAIT 10 seconds. Turn key off. Plug IAC and TPS back in. Turn key on ... pause .... now start.
MBT.. It's not a carburetor where you need max vacuum signal for fuel. EFI has more control. Get more air from TB blade by dropping advance and try to get about 0.40 or more TPS volts but not 0.76v that is too high. Resetting tps does not change voltage. But it does 0 tps percent and good. Ecm needs to know where 0 tps is!!
If tps is above about 1.60 percent you need to relearn TPS. Just like volts can kick you out of idle routine, it has a spark table reference for tps percent that does the same thing. Reset wait 30 seconds or until startup airflow has diminished before assessment and adjusting IAC. If your startup airflow is still adding air and you start iac calibration lol. Bad. Just wait....
If IAC went lower than it was probably because the isle advance was up. Spark, air, spark, air they work together for idle.
Think of the iac count as your tb blade opening. As it warms up and rpm table lowers the desired idle rpm based on ECT less air is needed to ? But our throttle body is a fixed blade opening so the IAC count is going to come down as your desired RPM comes down. So if your IAC count is too high you could be too lean because when you're lean it starts trying to command more airflow which in reality makes it provide more fuel. You first need to get the warm up fuel taken care of. Just start there man.
I have not been at my computer to see the logs.
Windows 11 and serial to USB adapter is an issue and either a post or Windows support website has a patch, can't remember.
So did a log this morning of a cold start and my iac counts were up in the 200s again. I waited for them to come down but at operating temp it only went as far down as 140. Yesterday I made sure that fully warm iac counts would be around 50-60. Then I noticed it got stuck at 170 for almost a minute. Fully warmed up, I increased tps to get counts down to 60. New tps was .30 v. Turn it off and then back on, the lean condition comes back all of a sudden and my iac nose dived to 0. It got me thinking maybe my IAC motor is having issues moving smoothly. So I swapped it out to a know good IAC and sure enough, with the same tps of .30 v, IAC counts were in the 50s and I no longer have a lean start issue. Starts and idles right around stoich. Hallelujah. I have base timing set at 24 and it seems to idle very well now without that lean condition. I am waiting a few hours for it to cool back down to 100 deg so I can be sure it?s fixed.
So as of now everything seems good. The only issue is my exhaust note. It sounds very muffled compared to when you first start it. I recorded a comparison at around 120 deg vs fully warm at 187 deg. and will upload it here in a minute. If it?s normal or a product of my exhaust system somehow then I?m fine with it. But I?d much prefer to get it sounding crisp like in the first video.
For some reason its not letting me upload video. Says the .mov file is invalid. I also tried .mp4 and it still gives me the same issue.
Turns out the muffled sound was a product of having the PID airflow controls too high. I halved proportional and integral and took 20% off of derivative. I also reduced the time between corrections from 1.2 to .4, reduced proportional min error to 20 rpm and lowered Integral min error to 10 rpm. No more muffled sound! I did some research and found some threads that stated large cams are often better off with a decreased PID and min error but not always. However in my case with my cam it seemed to do the trick. Now it finally has its natural lope and chops like it should at 14.7:1 AFR. Though my lean start up came back very briefly so I?ll play around with the OLFA vs ECT. Now the only thing left is to figure out why my O2 sensors are not working. I?ll have to find a pin out for them to figure out which wires are signal high/low, power, and ground. I know my sensors are not bad because they are brand new Bosch units only a few months old. It?s just weird that they worked before the swap but not after. I made sure to attach every ground, maybe I missed something? Fuses all looked good.
Yes. You have to save to YouTube or some other format and post the link. Can you imagine the bandwidth of this forum if everyone could post videos!
Bitter sweet, Glad the IAC was a part of the issue and you can move forward and get positive consistent results.
Glad it's working out.
Hello guys seems like your making progress but I have some concerns. Of all of the ls's with big cams that I have tuned, Idle vacuum has been the absolute least of our worries. With the PO1 pcm, big cam idle is really simple. Just provide enough airflow at idle. That's really it. If you have enough airflow, you have the right amount of torque potential. Idle spark is used to achieve idle rpm and dip recovery if any is needed. For instance. My procedure would go as follows if it were me working on your combo.
Write base file for big cam ls.
Set throttle stop to .69v on the TPS.
Reset TPS sensor.
Star and achieve idle even if I have to pedal it.
Let it warm.
Once idling on its own, make note of IAC position counts. I would expect somewhere around 125-140 on hot idle speed of 950 or so.
Shut down and set IAC minimum travel to 1XX. (what ever the IAC Stabilized close to).
Adjust maf or ve to what ever the short term trims were calling for.
Start the car several times to verify hot start airflow.
Verify idle short term trims.
Rev a few times and verify Idle return stability.
Adjust minimum IAC, fueling via short term trims, and start up airflow if needed.
Start test drive.
Air fuel Targets
Use Open Loop for HPtuners or closed loop wideband with Holley and other aftermarket ECU
Interpolate these values logically, i.e. the leaner a/f ratios go in the higher vacuum regions
Idle / Cruise = 15KPA to 50~KPA _ 14.8:1 to 15.5:1 air fuel ratio up to around 80mph most cars is cruise, [95mph @ 75kpa is not a 'cruise' use richer a/f ratio here]
Part throttle acceleration = 55KPA to 70KPA _ interpolate from 14.4 to 13.8:1 sometimes 13.5 for torque
70KPA to 85KPA approaching WOT 13.5 to 13.2:1 sometimes down to 12.8 is fine, even 12.5 but thats a waste usually
90KPA to 105KPA N/A WOT 12.2 to 12.8:1 , most common try 12.5 and wiggle on dyno, depends on spark energy/gap and compression ratio, fuel quality & iat
105KPA to 170KPA up to 7psi of boost factory head/piston gasoline 11.5 to 11.8:1
170KPA to 205KPA 11.5 to 11.8 gasoline, I let it go as low as 11.2 in HPtuners applications for reasons
215kpa+ no richer than 10.8 usually
by 240kpa switch to alcohol E50+ and lean back to 11.5 to 12.0 ranges for 250kpa+
additionally: 0-10kpa over 2900rpm, run it 13.5 to 13.8:1 for high vacuum to prevent lean tip-in at high rpm high speed
These a/f values intended to work for SR/RB/2J/LS applications 8.5:1 to 9.8:1 compression, plug gaps 0.022" to 0.034", 1992-2002 for Toyota/Nissan and 2002-2008 Chevrolet
For stock engines with aftermarket camshaft
5.3/4l80e/turbo playthrough
https://www.corvetteforum.com/forums...ge-budget.html
cancer research
https://www.mdpi.com/2306-5354/10/1/96
Ruebone: That may work for yours but the airmass at idle, I'll just say it may have worked for yours but there is better options. I can not imagine why you would have 1xx of IAC at idle if you open the TB blade to 0.69 volts! but again I am glad it worked for you.Originally Posted by reubone
WS6_lou has a large TB if I remember and if you start by opening to 0.69v you will hit 0 IAC long before that lol.
Louis may I suggest you go to HPT repository and download some stock 2001 T/A, Camaro and Corvette tune files, compare to your rolling idle settings, and set the rolling idle tables back to stock manual car values. You have a conflict in those settings. Go back to stock and see how that works for you but you will probably need more Cracker airflow at the problem areas. Make sure those areas are 100 percent calibrated before messing with Cracker and Follower tables or you can spiral out of control trying to get consistent results.
You either need better airflow/ better fans or lower thermostat. Yours are set to come ON at 157 deg in tune version 24, and they do come ON but have ZERO effect cooling and you still get 201 degrees. Try turning them off using green button special functions in Scanner, and see what it settles on NO FANS. Probably about 210 deg with normal radiator idling.
Ahh larger throttle bodies will reduce the amount of IAC needed for minimum airflow. The procedure is the same though. If no minimum IAC is needed after opening the throttle body it will show. The key to this operation is to get the airflow up to snuff so everything else dials in. Give it a shot sometime you might like it. Im not saying it is the absolute best way but for the dbc deals it is the easiest. Or is it the easiest for me...? Hmmmmm
A little tid bit. Not sure of it has been mentioned but the idle short and long term adapters for the base running airflow chase idle spark as much as idle rpm. If your actual idle spark doesn't match or your rpm doesn't match or both, the idle airflow trims will move around to try and line them up. Feel free to ignore the idle airflow trims if your progress is headed in the right direction.
Ruebone: Having a tps above .30v for my setup will decay IAC counts to 0 faster than a rabbit gets, well you know lol my method of determining tps voltage is to get it up to operating temp and then either open or close the set screw until IAC counts are between 40-60. If you start to get above .8% tps, stop, reset IAC and tps, and resume.
Hondaeater: I had a really messed up cracker table for some reason. Not sure how but im assuming it was to trying so many things on my own to figure it out but either making no progress or making it worse. What I ended up doing to fix the issue is set the cracker table back to stock, set 400 rpm cells down to 20 mph to 0, 800 rpm cells down to 0, and all rpm cells under 2500 rpm between 0-4 mph to 0 and smoothed the entire table a little bit. I then increased it by 10% and it seemed to take care of 90% of the stalling issues. I went and further increased the rpm and speed cells that caused the dip in rpm by 10% and it fixed 95% of it. Though I didnt fix the remaining 5% because I forgot to check where it was happeneing. Not a big deal, ill get around to doing it this monday. I dont think I messed with the follower table much, I may have just shifted it a cell or two closer to 0 and it seems to return to idle exceptionally well. You can rev it to the moon and itll almost free fall back down to about 900 rpm and just completely stop without fluctuating. Now, my fans are set to kick in at 157 mainly due to how hot it gets. From what ive been told iron blocks hold more heat than aluminum ones and take a lot longer to cool off. However the logs dont show the fans kicking on because I was doing RAF logs and disabled them in the scanner.
Right now, im 90% done with the car after 2 god damn years of pain and suffering. The only thing left to figure out is the lean start up issue (confident the OLFA vs ECT will negate this since it only happens for a little bit after a hot restart just havent got around to it yet) and more importantly the O2 sensors not reading at all. Though they get power. Any suggestions on that would be greatly appreciated.
They have already answered this in the same way as I think, not all engines are assembled in the same way, not all engines use the same setup, it does not usually happen like this, from my experience you always have to look for what the car asks for if you are in an AFR of 14.7 and you can notice an imbalance in the idle we must eliminate this balance there are many engines that are in 14.7 according to their cam and their configuration may be very good but there are simply cars like yours that run a leaner AFR, they can go much better than an AFR 14.7 in my opinion always follow your engine if your engine feels excellent in 16AFR leave it there, at idle it will not affect you at all since there is no power that can do it, I have seen engines start without injectors. .. just avoid the KNOCK
Well I figured out theO2 sensors. Apparently the previous owner must have switched the front and rear o2 plug wires at the ecu. I plugged in the front o2s to the rear o2 plugs and now I can go into closed loop. Sweet.
My RAF is also spot on but for some reason at full warm up my scanner reads my base airflow at 12.4 when it should be 11.1. This is causing my STIT and LTIT to subtract about 1-1.5 g/s. Not sure where that additional airflow is coming from.
Also my CL commanded AFR is 14.7. How do I adjust this to command somewhere around 17:1? It idles much smoother at 17-18:1 than at 14.7:1.
Question: What do you guys set your "cell hits required" to in the scanner? I have a "VE CL Error" graph that plots RPM vs MAP (KPA) and adds up both STFT and LTFT. When I change "cell hits required" to 1 I can see its wanting to add 20% fuel when I blip the throttle. I have not gone for a drive yet so I cant say for certain if its just something that happens at idle or if it also happens while driving. Just wanted to share with yall my findings to see what your take on it is. Ill include my logs and tune file. One log is a cold start to get my RAF dialed in and the other is a hot start to test CL. Thanks.
Cell hits requires the data to be more consistent. Example: If you blip the throttle the parameter data you are watching fills in the graph/ table because it passed by so fast in a particular cell point it is unreliable but it shows up populating the table, but if 5 hits required, only those cells that had enough dwell time for the data in that cell will populate. Hope that makes sense.
I do not see the log used to get CL Fixed New RAF Log?
Is it correct to use the LQ9 Firebird Tune3.0 29 tune for the CL Test New log?
You have changed more than just BRA between those 2 logs, one is closed loop and one is OL. You changed the desired RPM too and that will change the desired idle airflow lol. You need to quit sabotaging yourself. If you change rpm that changes the BRA and idle desired. How does it idle overall at 800? Stable? Looking at your TPS and TB voltage in CL Test New log they move. That blade is moving. Look at IAC after throttle blip. Once the o2 had better heat, flow look at the desired idle air and compare the change to Dynamic airflow. Dynamic does not move much does it? In this CL log around 190 degF the fuel trims dropped after that blip nearly in half. This is why I said you need to go drive thru the gears up to about 3000 - 3400 as well as the idle log because it will reveal if the injector data is accurate in the part throttle area. Idle and part throttle have a different "fix" to dial in the injectors than the upper rpm and PE, WOT that used the IFR. But I have not seen a stable idle and then a nice light throttle drive up to about 3000 rpm so I can not help you. If it was in there the tune file posted VS. logs are not from the same tune file. Changes get made for idle then more changes are done in the "background" not posted and then get a drive log but the idle log does not have the same calibration as the drive log and it is just a MESS. This has taken me longer to write than I wanted to spend on it and that is my point. Some people/"tuners" in the forum may have more free time to troll or worse give bad advice, and the file management is so Screwed up it takes forever to look over what they really have and then that data, after spending WAAYY too long sorting out the good data from the bad, inconsistent data with missing tune files and more there is no time to HELP!! So please help those so they can help you. Rant! Rant! Rant! ..... whew, ok I feel better...
There is so much to review to be of help on your log, and too many changes and no tune posted as I mentioned, I do not have the time for it and some, not all, have the time but not the experience and you get bad advice. Do yourself a favor here.
Please label the tune to match the log. Something like you did but Tune3.0 29 I see that is not a revision but a DATE lol. Dates are ok for you but many different tune/logs and with the same date can get confusing as to the order or revision.
It may be easy for you to make sense but posted tunes do not have the time they were made only when they were downloaded from the forum. That may or may not be the same day it was made and there is no way to know the order created without the creation list or BETTER LABELING.
This is only an observation for proper file management to you, others, anyone who finds it useful. When you are working on multiple cars not just 1 like you, on MY end it is a mess. Missing tune files and logs which make perfect sense to YOU are difficult and time consuming for those trying to help.
Again.. Please consider relabeling those you have now, just open the logs and re-name it for the tune file used. If there is 2 logs for the SAME tune revision, use letters like this...
Tune: LQ9 Firebird rev(ision) and xx#.
Log: LQ9 Firebird rev(ision) xx# = tune label numerical reference,
and if you have 2 logs of same tune, say like...
LQ9 Firebird rev(ision) 01 for a Cold Start for example and
LQ9 Firebird rev(ision) 01a for the same tune but different data. A cold start and then start a NEW log (01a or 01b etc) for drive data gathering or maybe you are focusing on a transmission or misfire or whatever but the tune did not change only what parameters you were logging for so using a letter not a new number like LQ9 01 and new log, but SAME tune labeled LQ9 02 will make the 02 log look like it goes with the revision of the tune with 02 in the file name. I need to go and hope you see what I mean?
If you have time to go back and re-label the logs and tunes or at least going forward start, would help everyone.
If it ends in .hpt file extension it is a tune file, .hpl is a log so no need to add that in the label, ... it is self evident. Opening a Log in Scanner does not list the Tune files anyway.
It is not my intention to promote " do it my way or the highway " and if anyone has a better method for organizing please suggest it. This has worked for me and may be useful to someone who reads these mini-novels.
I am probably not going to be available for some time. I have to many projects I am involved in but will try to check back periodically.
Stay tuned,
Hondaeater.
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