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Part throttle leaning out.

Posted: Sat Mar 28, 2009 12:19 am
by delinquentracer
When Im cruising at different spots in the rpm range ( depending on the gear ) and also when Im lightly accelerating I have blips where the engine will lean out and then pull itself back to normal.

What to fix/change for this one?

Posted: Sat Mar 28, 2009 12:54 am
by Liger
ppctx and I are currently working on finding out why this is happening. We are having a similar issue with part throttle boost causing a lean condition under ~3000RPM

Posted: Sat Mar 28, 2009 2:17 am
by flip240
what kind of ecu are you guys running? emissions removed?

Posted: Sat Mar 28, 2009 10:38 am
by Liger
I have a Federal 5 speed ECU for a 1993. My emissions is removed, no PAIR system or SCV either. Since it's Federal, it doesn't throw codes. I've had this problem even when I had all of that junk hooked up. I'm fairly certain it has do with whether or not the ECU can sense which gear you're in, or it's accessing some unknown pulsewidth map.

Posted: Sat Mar 28, 2009 11:45 am
by delinquentracer
Im running a 95' OBDI ecu with calum rt board. Emissions all removed, no codes thrown for it.

Posted: Sat Mar 28, 2009 3:14 pm
by flip240
Liger wrote:ppctx and I are currently working on finding out why this is happening. We are having a similar issue with part throttle boost causing a lean condition under ~3000RPM
are you guys running lean while actually in boost, part throttle?

Posted: Sat Mar 28, 2009 6:19 pm
by ashy-larry
delinquentracer wrote:Im running a 95' OBDI ecu with calum rt board. Emissions all removed, no codes thrown for it.
How much of a PITA is it to tune the s14 calum rt. I have a 95 kat that im contemplating converting to s13 harness and using s13 calum b/c ive read its much easier to tune, from your experience how is the s14 ecu? any feedback would be cool as i normally dont post on this forum b/c i tend to read instead of post.(hence the low post #)

Posted: Sat Mar 28, 2009 6:30 pm
by ghostchild316
Have you tried setting 0559,055A, and 055B to zero? I had the same problem too and this did the trick for me.I also DON'T use o2 feedback.

Posted: Sat Mar 28, 2009 7:20 pm
by delinquentracer
ashy-larry: Tuning it isnt bad. Theres just a few things you cant do only because no one has completely figured out the ecu yet. Calum said he is working on it. So hopefully soon it will be fully accessible to all of the parameters. Although, then someone has to test them out.
I have mine driving with good cruising afrs and good boost afrs so far. This is on a minimal amount of time actually driving around tuning also.. just an hour or so.

ghostchild : Are you running an s13 ecu in order to disable O2 feedback?

Posted: Sun Mar 29, 2009 5:19 am
by ghostchild316
S13 Calum RT

Posted: Sun Mar 29, 2009 10:41 am
by ppctx
flip240 wrote:are you guys running lean while actually in boost, part throttle?
Yes, that's the problem. I've posted one of my logs on eccs, in the de section, to see if I could get help there but no one has taken a look at it? Its basically low injector pulse width, with a very pronounced jump at some point that that I have not been able to correlate to a specific rpm, tp, speed, etc.
delinquentracer wrote:ashy-larry: Tuning it isnt bad. Theres just a few things you cant do only because no one has completely figured out the ecu yet. Calum said he is working on it. So hopefully soon it will be fully accessible to all of the parameters. Although, then someone has to test them out.
I have mine driving with good cruising afrs and good boost afrs so far. This is on a minimal amount of time actually driving around tuning also.. just an hour or so.
Glad someone else has sought out Calum's help with this so I'm not just one weird guy with my own issue. I have sent him some of my bins and logs to demonstrate the issue. He said he felt it was a table/function causing it, similar to the 0559,055A, and 055B 6 deg timing retard stuff. If it’s a bin issue, he’ll be able to find it on his bench.
ghostchild316 wrote:Have you tried setting 0559,055A, and 055B to zero? I had the same problem too and this did the trick for me.I also DON'T use o2 feedback.
Yes. I've tried changing so many known maps, you would not believe. Comparing setups with Liger and now delinqentracer, the issue exist on different combos of ecu, calum/nistune, year, auto/manual base ecu... Latest comparisons with Liger, the only thing we have in common, besides the issue, is the transmission neutral position sensor. Mine ain’t hooked up, his isn't being detected. DR, what's the story with your neutral sensor?

I'm down to it's either the neutral position sensor or it's an unknown in the bin code. What surprises me is that more people have not noticed the issue. Even if people were to post and honestly say that they do or do not experience a lean condition at partial throttle in boost (especially in 4th/5th gear), that would help. I’ve had someone PM me a couple of months ago, describing the same issue. At the time my thoughts were that I don’t spend a lot of time in partial throttle boost but now this is annoying and a problem.

Posted: Sun Mar 29, 2009 10:32 pm
by delinquentracer
I believe that my neutral position sensor is disconnected also due to the 5 spd swap and keeping the auto ecu. Hazy on remembering for sure, I did the swap like 3 years ago, but Im pretty sure.

So.. Ive been monitoring and I notice that my afrs lean out at part throttle conditions around 20-25 % throttle no matter what gear Im in. Im not sure of the TP yet, Ive just been watching my afc. Right after that Im in cruising conditions and it goes back to normal. This is basically normal light acceleration around town. This is the only time its happening.
Ideas?

Posted: Mon Mar 30, 2009 3:05 am
by flip240
I've had a different issue w/ leaning out at 3000 rpms when the engine is cold, but i haven't figured it out either. you guys might try my next steps (when i get to them), which is monitoring injector duty cycle to see if it's the ecu issue or a regulated air issue (e.g. iacv or the egr canister control solenoid valve)

Posted: Mon Mar 30, 2009 9:09 am
by Liger
It's ECU related issue. We have already logged most every parameter and there is a clear area where the pulse widths do not raise at all until you go past ~3000RPM then they suddenly shoot up to where they should be. Happens absolutely every single time in 4th or 5th, and occasionally in lower gears.

Posted: Mon Mar 30, 2009 5:54 pm
by delinquentracer
What do you mean ECU related? Meaning we cant change it? Or...?

Mine happens in any gear...

Since consistently at the same times I would venture to say changing the region in the fuel map might work, but I dont really want to go that route yet.

Posted: Mon Mar 30, 2009 6:11 pm
by ppctx
Well, that's why you have a RT ecu. Richen that area up, log it and see if it fixes your problem. If that fixed it for me, I wouldn't keep posting about it.

ECU issue, as in it's in the bin code, can be changed but what table/map/function is it? I've adjusted/changed most all the known ones that I think could have any thing to do with it.

Calum, please help me out of this hell hole I’ve come to know as partial throttle boost..

I'm surprised know one else has chimed in with "I know I dont have that issue" or "I've experienced that also but just haven't worried about it"

Posted: Mon Mar 30, 2009 8:16 pm
by delinquentracer
I just felt that changing the map isnt finding the real issue. Ill try it though.

Posted: Tue Mar 31, 2009 6:29 am
by ppctx
I was only half being a jerk. Your issue very well could have to do with too little fuel in the map as boost comes on. When I added fuel, it simply made my injector log look like saw teeth (but still not enough fuel even at the peaks) until the point that this unknown limiter ended and allowed fuel to increase properly. I didn’t just add a little, I copied the columns from the full boost TP columns and pasted them starting at the column just before 0psi all the way over to full boost.

I am genuinely curious to see how increasing fuel in the fuel map works for you.

Posted: Thu Apr 02, 2009 12:14 am
by delinquentracer
I need to do some more logging and see if I can notice any more patterns. Ill let you know how it goes.

Posted: Mon Apr 06, 2009 12:02 am
by Liger
Well I have found what is causing our problems and found the solution as well. The map that needs to be changed is 0200. In TunerPRO the map is all called TPS Enrichment Trigger and is measured in TPS volts, in NIStune it's called the Injection Response Map and is measured in values and temperature. I need to notify Matt to change the displayed values in NIStune to volts.


Essentially this map prevents the main fuel maps from being accessed under light to moderate load conditions while under 3200 RPM for the sake of fuel economy I'm guessing. It attempts to keep the fuel mixture as lean as possible. In the stock configuration you must depress the the throttle to get a voltage of 4 volts before this is overridden.

If you adjust the map in TunerPRO, like I did, to around 1.80 volts, you'll allow the ECU to access the main fuel maps just before you start to build boost. In NIStune, 1.80 volts is equivalent to a temperature value of 90 on the map.

Posted: Mon Apr 06, 2009 1:13 am
by emo_tactical9
Amazing! Well done. I'm assuming this is for a S13. Is that right?
Has anyone with a S14 had this problem yet?

Posted: Mon Apr 06, 2009 1:28 am
by Liger
Yes, so far this is only confirmed with the S13 KA24DE.

Posted: Mon Apr 06, 2009 6:40 am
by ppctx
Oh Boy, can't wait to get home today, great work!!! I'm going to give you a big sloppy wet kiss if this fixes me up..

In my xdf, address 0200 is a 16 row, 1 column map. Current values are 203 for the lower half, 255 for the upper half and there is no conversion equation applied to the values.. You just changed them all to 1.8?

Edit: I think I need to change my conversion equation to value x 0.02 to display the values as voltage. Did you set all the cells to 1.8

Posted: Mon Apr 06, 2009 10:07 am
by Liger
In TunerPRO is already converted them to volts. But in your case, 90 would be the correct value. I loaded the modified .bin into NIStune and 90 was the value it came up with.

Posted: Mon Apr 06, 2009 6:11 pm
by nis720
I'm still N/A and i have the same issue with mine. I've tried different ECU's. I think it's all related to the EGR being eliminated.

Posted: Mon Apr 06, 2009 6:57 pm
by 8-bit
tune it.

Posted: Mon Apr 06, 2009 7:18 pm
by delinquentracer
On the s14 xdf it has E200, its called injection response.
The map is a 16 row, 1 column. The values on the left say Load for that column. They are all 203. The column next to it doesnt have a representation above it, but all the values for that column are 203 also.

What do you think?

Posted: Mon Apr 06, 2009 7:37 pm
by emo_tactical9
Can you post a screen shot and perhaps email me your xdf?
Mine has E200 as well, but its just a scalar, with 203 being the value in the stock bin I have.

Posted: Mon Apr 06, 2009 10:08 pm
by ppctx
Oh, you sexy bich. I'm gonna give you nasty.. nasty prison sex.. but in a gentle and caring way. It's hard to believe more folks haven't chimed in from the get go, but this is one of the biggest fixes I've seen. Thanks again, this is all I can give you for now due to the distance.. So cool
















Image

Posted: Mon Apr 06, 2009 11:52 pm
by Liger
Not a problem, and for everyone else, do what I said. A value of 85-90 will be 1.8-1.9 volts.