Still get oscillation coming to a stop
Thread Starter
Joined: Aug 2004
Posts: 11,258
Likes: 146
From: Pace, FL
The .71V is not what it was set to. I had it set at .57V. So it just suddenly changed overnight. So either the TB shaft moved or the TPS is reading weird again.
Either way, I don't have any follower airflow below 2% and my idle routines kick in under 1.3% so I can live with .8%... hell it was .4% forever at .57V. It never would zero out. But I don't like it being an issue. Car idles even without adaptive spark on, so I didn't notice it at first. But then I glanced over and saw 3.4% TPS and 1.2g of follower airflow. And I was idling.
I'll try more Proportional airflow as well. I have a little more than stock. But it's such a low number. Like a 40rpm drop is .0078g.
I've been thinking of getting a Roadrunner PCM and using EFILive. Then everything can be tuned in real time...
Either way, I don't have any follower airflow below 2% and my idle routines kick in under 1.3% so I can live with .8%... hell it was .4% forever at .57V. It never would zero out. But I don't like it being an issue. Car idles even without adaptive spark on, so I didn't notice it at first. But then I glanced over and saw 3.4% TPS and 1.2g of follower airflow. And I was idling.
I'll try more Proportional airflow as well. I have a little more than stock. But it's such a low number. Like a 40rpm drop is .0078g.
I've been thinking of getting a Roadrunner PCM and using EFILive. Then everything can be tuned in real time...
Thread Starter
Joined: Aug 2004
Posts: 11,258
Likes: 146
From: Pace, FL
Now it's back to normal. It's a short somewhere in there.
Oh well.
I will say this... I played with the follower numbers a little more. And I didn't like the way the lower % felt without any sort of multiplication. But I didn't like say 6-8% cruising with a jacked up follower. So I did some calculations on what would be ideal in the 6-8% range and adjusted the 3.5% and 13.5% columns to give me the follower I wanted there and altered the others based on different things I had seen or felt in playing with it. So it drives pretty much the way I want it to at low speed or in parking lots with a little more follower and a little less follower in the cruising range.
And taking additional timing out of the very low cellmass areas makes coastdown much less surgey.
The only remaining issue I have is when the A/C is on. I can get some surge on coastdown. And I've tried taking more and more airflow out of A/C. And it doesn't seem to help. The added load makes the car hiccup a bit. It's lean and the timing is around 20-22 degrees in these areas.
Any ideas?
Oh well.
I will say this... I played with the follower numbers a little more. And I didn't like the way the lower % felt without any sort of multiplication. But I didn't like say 6-8% cruising with a jacked up follower. So I did some calculations on what would be ideal in the 6-8% range and adjusted the 3.5% and 13.5% columns to give me the follower I wanted there and altered the others based on different things I had seen or felt in playing with it. So it drives pretty much the way I want it to at low speed or in parking lots with a little more follower and a little less follower in the cruising range.
And taking additional timing out of the very low cellmass areas makes coastdown much less surgey.
The only remaining issue I have is when the A/C is on. I can get some surge on coastdown. And I've tried taking more and more airflow out of A/C. And it doesn't seem to help. The added load makes the car hiccup a bit. It's lean and the timing is around 20-22 degrees in these areas.
Any ideas?
Thread Starter
Joined: Aug 2004
Posts: 11,258
Likes: 146
From: Pace, FL
Btw, I enabled DFCO just for ***** and giggles. Haven't had it on in a long time.
When it kicks on, you can feel the motor relax and the scanner shows timing holding and the O2s stop switching.
But the best part is no bucking on coastdown...
When it kicks on, you can feel the motor relax and the scanner shows timing holding and the O2s stop switching.
But the best part is no bucking on coastdown...
Thread Starter
Joined: Aug 2004
Posts: 11,258
Likes: 146
From: Pace, FL
Ordered a new NTK wideband since my other one was on its way out.
I'm going to try and rev in gear or in PN and get some data logs on some different areas of the VE table to see if I can figure out why it still doesn't catch perfectly after I rev. It almost always undershoots down to 600rpm unless I jack up the follower to over 3g/sec at lower TPS regions. Even though I had it working pretty well, it was still doing that. So when I'm driving it still wants to bog sometimes. So I figure if I can get it to return to idle cleanly without a bog then maybe it won't bog on the street.
Because, frankly, it should not need the IAC open at 140 counts to catch itself on return to idle.
I'm going to try and rev in gear or in PN and get some data logs on some different areas of the VE table to see if I can figure out why it still doesn't catch perfectly after I rev. It almost always undershoots down to 600rpm unless I jack up the follower to over 3g/sec at lower TPS regions. Even though I had it working pretty well, it was still doing that. So when I'm driving it still wants to bog sometimes. So I figure if I can get it to return to idle cleanly without a bog then maybe it won't bog on the street.
Because, frankly, it should not need the IAC open at 140 counts to catch itself on return to idle.
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
Thread Starter
Joined: Aug 2004
Posts: 11,258
Likes: 146
From: Pace, FL
Yeah. So it needs to be lean. And maybe less timing. Maybe both.
But I got my new wideband today. Plan to do a refresh street tune session on Saturday to make sure my fueling is right. I was getting such inconsistent stuff with my last wideband that I just avg'd it out, kept my WOT fueling from the previous cam, and watched my narrowbands to see if I was within 5-10% (and I was). So I left it.
But I got my new wideband today. Plan to do a refresh street tune session on Saturday to make sure my fueling is right. I was getting such inconsistent stuff with my last wideband that I just avg'd it out, kept my WOT fueling from the previous cam, and watched my narrowbands to see if I was within 5-10% (and I was). So I left it.
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