s300 on b18c cannot get accurate idle

s300 and SManager software questions & answers
Alkilgore
Posts: 10
Joined: Wed Dec 26, 2012 12:14 am

s300 on b18c cannot get accurate idle

Post by Alkilgore » Wed Dec 26, 2012 12:35 am

I am currently working on a b18c integra. I started with an overly rich map and am trying to get it to idle well. I can get it close , it will start idle high, then come dowm a bit then surge than try to catch up, then surge again. I have taken apart the IAC and cleaned it well, and so I hope it works. I had noticed thoe, the surge occurs when the duty cycle on the s300 goes to -0- then back up. I am running a mtxl wideband on d10 eld wire and think I have it configured correctly. Any ideas ? Also when trying to change the fuel table I grab the cells and make the change and then the car stumbles and dies. ( even if I make a minor change +1 + 2 etc. Then after restarting the car will not rev , it goes to the rev limiter and engine light flashes ??
Any ideas?
I am new to this .......
Lasly. the wideband while at idle shows different AF numbers than the s300 software. I have put in the correct offset voltages and tried the voltage compensation to no avail. They are off 1.5-2 on af .
This car has street / race cams so I understand Idle may be hard to stabalize.
thanks
Al

shiroitenshi
Posts: 60
Joined: Sat May 19, 2007 9:24 pm

Re: s300 on b18c cannot get accurate idle

Post by shiroitenshi » Wed Dec 26, 2012 8:12 am

The hondata b18c ITR map is rich for me as well, and I am from Asia, where ambient temps are 30-40deg Celcius.
Plus crappy gas, and stock maps even have too high an ignition. So depending on your weather, you may need to run slightly retarded or not.

a) the surging can happen if you screwed up your map a lot, the engine revs up, then meets a load vs too lean/rich that cannot sustain the engine speed, and drop back to the previous rev vs load point. It can also happen if you have a vaccuum leak.

b) even with cams, the car can idle well, it is just that the compression leak from huge primary lobes ovelap will somehow make the car idle slightly 'lumpy'. This is highly dependent on the overlap you run on the cams.

c) If you are not turbocharging, the B18C ITR basemap works well, but need to retard in my case since my country is hot, and cannot sustain the basemap's ignition at high load without incurring knock. If you live in US, I think the map would work well enough, but you would need to retard ignition if you live in a hot country/has lousy gas/petrol.

d) calibrate the timing on your car with hondata, use a timing light, go to Online-Set timing to lock the timing, and get it right. If you do this, then the timing you read in hondata will roughly be the same timing with the engine. (never mind that without measuring the actual TDC means it is off a bit, but as a starting point, this is fine)

e) I had problems with AFR not reading right a few years ago. All I can say is, if you have to add ground offset, expect accuracy to suffer. I power my wideband direct from battery, and the signal & ground wire to the ECU (I use a jumper harness), and I have zero offset required.

I even tried using slightly thinner gauge wire for the wideband initially, and all resulted in poor accuracy/requiring voltage offset. I am using LM-1 by innovate (yes, it has worked well for me for the past 6+ years, and still working now). I use D14 O2, which is limited to 3.8V by internal circuitry. However, with the wonders of programmable input, I set the scale to 20AFR at 3.8V, and 10.1 at 0.05V, with the LM programmer (the LM2 is the same, just smaller)

Accuracy is +/-0.2 AFR.
Works like a charm.

Tuning without a basemap is difficult if you're new. Always start with a basemap.
Once you get a grasp of the system, you can actually start with a blank map and build a basemap without even looking at the car. That's what I did for my ITB, as the hondata's basemap for ITB was so different from my setup, that I had to resort to making my own basemap to get the car to start and be able to drive around.

Also, understand how load, map pressure, and rpm correspond to the fuel and ignition values on the chart. Without this knowledge, you will have a hardtime creating your own basemap from scratch.

Alkilgore
Posts: 10
Joined: Wed Dec 26, 2012 12:14 am

Re: s300 on b18c cannot get accurate idle

Post by Alkilgore » Wed Dec 26, 2012 4:54 pm

Thanks for the reply. Yea I am overseas as well in Guam USA. So our weather should be comon.
The surging is happening after the car is reved and then throttle released. The engine will high idle for 15 seconds then go to a low idle, then surge. I had tried to figure the IAT speed to no avail.
Car seems to rev fine with the map I have , just the idle that I can't seem to get. No vacume leaks I can detect. I recently rebuilt the entire engine. Map pressure at idle is .900 or so ( not good )
Could be cams or not broken in well enough.
What is bothering me also is after adjusting the fuel map, the car will die and when restarting it will act like it's rev limiting. ( only making changes of 2-3% )And running crappy.
How do I post the map I have to let you look at it?
Let me know.
thanks
Alan

shiroitenshi
Posts: 60
Joined: Sat May 19, 2007 9:24 pm

Re: s300 on b18c cannot get accurate idle

Post by shiroitenshi » Wed Dec 26, 2012 5:27 pm

save your map, and try hondata's itr base to see if the problem occurs (keep an eye on AFR amd make sure to check for knock while doing this), if it does, it is your engine setup, if not, then it is likely your calibration file. it is uncommon but sometimes the map gets corrupted from frequent loading and downloading. you can post the calibration file .skl here. i assume you are using a normal plenum intake and not itbs.

you can post the calibration here, but without accompanying afr readout that is accurate, its kinda pointless

if the calibration file is the problem, make a new map and copy paste everything over, and make sure the parameters are set similar to the one you already have.

Alkilgore
Posts: 10
Joined: Wed Dec 26, 2012 12:14 am

Re: s300 on b18c cannot get accurate idle

Post by Alkilgore » Wed Dec 26, 2012 7:59 pm

I finally got it to idle pretty well. I also did what you said about using battery voltage and ground. I had also confiured it a bit off so I ended up with numbers very close to the AF guage + or - .2-3
Af at idle is showing 12.2-12.4 I tried to get them closer to the suggested 14 -1 but the car would start to hunt up and down.
I think I may have a problem with vacume at idle. it sits at .925-.930 there. I adjusted the throttle body air screw and it improved a bit. I am feeling the camshafts are very high lift which causes low vacume numbers.
I am going to try now to tune the rest of the power range. what AF reading should I shoot for ?
I guess seat of the pants is going to be my guide as we have no dyno here.

I still have no idea how Thanks
Alan

Alkilgore
Posts: 10
Joined: Wed Dec 26, 2012 12:14 am

Re: s300 on b18c cannot get accurate idle

Post by Alkilgore » Wed Dec 26, 2012 8:03 pm

Heres the file. Sorry I'm not so good with sending stuff.
Attachments
idleok1.skl
(40.54 KiB) Downloaded 82 times

shiroitenshi
Posts: 60
Joined: Sat May 19, 2007 9:24 pm

Re: s300 on b18c cannot get accurate idle

Post by shiroitenshi » Wed Dec 26, 2012 8:57 pm

you'll never get the ignition right without a dyno. start conservatively with timing, if you're tuning on private roads, get a proper knock monitor, else the moment you realise the ignition is too much, it is too late. since you are likely going to use left foot on brake as variable load. and with so much going on, it might be a bit much to take in at one go.

there is no 'right afr' at idle, as there is no load at this point, you just need enough fuel and timing so the engine rpm stays constant. my car idles at 15-16 afr at 21degs. with air conditioning naturally i have to give it more fuel to retain the same idle speed. so 14.0 with a/c on.

what happens with the rpm drop when you decrease the fuelling to hit the 14.7 afr is that you reduced powet to the engine, due to the timing and fuelling not being spot on, depending on car, stable idle is achievable with 15-13 afr with 16-20+ timing,. if the cam is leaking and giving you the lumpy idle, you tune the next box that it drops the rpm to. with this, you reduce the rev it drops to, and when you get it right, it should be roughly stable, probably with the lumpy idle. due to the engine not being able to sustain 800rpm idle. the 500-750 rpm index is there for a reason... tune those to reduce the rpm drop, soon you will find the map sensor reading slowly decrease as you get the tune right.

even then you can eliminate it simply by running a slightly higher idle speed.

Alkilgore
Posts: 10
Joined: Wed Dec 26, 2012 12:14 am

Re: s300 on b18c cannot get accurate idle

Post by Alkilgore » Thu Dec 27, 2012 5:30 pm

I did a bunch of trying to tune yesterday. I got the map to work for idle and partial throttle opening. But the car staggers during hard acceleration. How do you data record ? I need this to get an idea where to tune.
I have to say... This is a bit harder than I had figured.
Also, how do you use the overlay
Thanks
Alan

Alkilgore
Posts: 10
Joined: Wed Dec 26, 2012 12:14 am

Re: s300 on b18c cannot get accurate idle

Post by Alkilgore » Fri Dec 28, 2012 12:02 am

OK, I got the car to run pretty well, except being a bit rich. Only problem I am having is the TPS signal.
When reving the car , the tps works for a few seconds then drops to 0. I checked it while the engine not running and it shows full throttle range. I am not sure if the tps is sending signal to the s300 while running or is the s300 just shutting it down. Could possibly be a bad tps that need vibration to make it fault out. any experiance with this ? P.S. the engine goes into surging while the tps shows 0 ???

Almost there....
thanks
Alan

shiroitenshi
Posts: 60
Joined: Sat May 19, 2007 9:24 pm

Re: s300 on b18c cannot get accurate idle

Post by shiroitenshi » Fri Dec 28, 2012 5:46 am

tps sensor might be faulty. there are case where tps wprks fine, except for a few 'blank spots'. test the tps with a multimeter to check that you hvae no blank spots as you go from zero to full throttle. . when tps gives 0v to the ecu, DFCO kicks in cutting off fuel resulting in jerking while acceleration.

Alkilgore
Posts: 10
Joined: Wed Dec 26, 2012 12:14 am

Re: s300 on b18c cannot get accurate idle

Post by Alkilgore » Tue Jan 01, 2013 11:29 pm

I am still trying to get this thing right. I checked the tps with a volt meter and with the throttle set at where it will idle the tps has .55 volts. I have run out of slot on the adjustment to lower it to the specified .45 v. whats weird is when I use s300 to see the idle opening it is showing -.15 . Is there some feild where I can adjust the voltage for this to show .45 v or is it needed ?
last week, I re adjusted the intake cam to 0 on the adjustable sprocket and the map whent up so I am going the right way. I realize these cams are a bit much and have very low vacume at idle.
one thing I notice also, is the timing adjustment at idle seems to be 7-12 degrees advanced. You had mentioned 20 or so. How do I do this and still have the timing map follow the correct rpm advancement? Can you look at the map and see what I am not ??
Please help.
Al
Attachments
lastcall013.skl
my last map
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Spunkster
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Re: s300 on b18c cannot get accurate idle

Post by Spunkster » Wed Jan 02, 2013 2:02 pm

Details on calibrating the TPS can be found in the Help file: http://www.hondata.com/help/smanager/tp ... =scale+tps

Alkilgore
Posts: 10
Joined: Wed Dec 26, 2012 12:14 am

Re: s300 on b18c cannot get accurate idle

Post by Alkilgore » Wed Jan 02, 2013 11:55 pm

I tried several times to get the car to idle by setting the tps and settings on the s300 software. I can get it close to ideling at 900-1000 rpm. Now it seems when I open the throttle slightly, to 2000 rpm I get this hunting high then drop, high then drop. The injector duty is going to zero when it drops. Thus I think the fuel cut is coming in for some reason.
I had set the fuel cut at .5% 1. percent, o percent and it does not change the hunting.
TPS value is strangly 0 % and 1% sometimes. With a volt meter the tps is flawless. ( vehicle off )
I tried to re set the values in the overun fuel cutoff and the hunting gets worse. the setup is 19-19-16 in the 500-2000 rpms

what other reason would the injectors be cutting off?

Need some help , this is strange. other than this the car runs great.

Please sombody chime in...
thanks
Alan

shiroitenshi
Posts: 60
Joined: Sat May 19, 2007 9:24 pm

Re: s300 on b18c cannot get accurate idle

Post by shiroitenshi » Thu Jan 03, 2013 12:52 am

like mentioned before, check the entire tps range, not just from closed throttle, read it from 0.5 to 4v+ if there is a blank spot, then replace tps. hondata is reading correct. most of the time i find that hondata 0% is about 0.5ish V.
what voltage you see at the multimeter isn't necessarily what the ecu gets. voltage drops might happen due to grounding differences.

timing light is synced by using the set timing option in smanager, do this each time you reset intake cam timing.
checking timing using an adjustable timing light and ab aftermarket crank pulley that has 0 to 30deg marks is nice for knowledge but hardly necessary if you have a knock monitor (via electronic sthethoscope or the mechanic's stethoscope.) to find the max ignition you can run on a certain gas.

when opening throttle slightly and hunting is normal. essentially you are creating a vacuum leak via throttle butterflies. it is only a worry if dfco kicks in while coasting at light throttle, resulting in jerking. check tps range, if you get jerking. some rare cases, tps wires are frayed or has bad conductivity

can also cheat the tps by setting your tps to 0.8v and putting 0 and 100% in tps calibration and dfco to 0%, needless to say this kills your fuel economy and also disables iacv from working, but it is a good method to identify and troubleshoot the issue of dfco triggering and resulting in jerking while driving. i prefer to set the tps right the first time though.
Last edited by shiroitenshi on Thu Jan 03, 2013 1:21 am, edited 1 time in total.

shiroitenshi
Posts: 60
Joined: Sat May 19, 2007 9:24 pm

Re: s300 on b18c cannot get accurate idle

Post by shiroitenshi » Thu Jan 03, 2013 12:56 am

usually i just ignore hondata numbers and set my tps to 0.5v and calibrate tps in smanager, not caring about the numbers. it is useful when i have to calibrate tps without a multimeter tho.

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