Past 0.55v for closed throttle = no 0% TPS after reset?
05-12-2017, 08:17 PM
#1
Past 0.55v for closed throttle = no 0% TPS after reset? On a 98-04 ls1/ls6 pcm is it true that you cant go past 0.55v for closed throttle or you wont enter idle cells and you wont see 0% TPS even with a TPS reset?
If so then what if you need more air in than 0.55v to idle properly? Surely you don't need to drill a hole or slot the TPS sensor holes to get the voltage up past 0.55v so that you can get TPS back to 0% and get IACs where they need to be. What is the correct way to do with with no drilling?
I have mine set to 0.55v and my idle air control position is 170 at 145 F engine coolant temp. I should be around 60.
at wot I see 100% TPS at 4.53v
at idle I see 0% TPS at 0.55v
Sure it would be great to adjust the throttle body open until warm idle has a IAC Count of 50. Then reset the TPS by unplugging it and do a key cycle then off and plug it back in. But if you are over 0.55v, this won't reset the TPS % back to 0 for the voltage the TPS Sensor is sending. At 0.65v the TPS % reads 0.4% even after reset.
If so then what if you need more air in than 0.55v to idle properly? Surely you don't need to drill a hole or slot the TPS sensor holes to get the voltage up past 0.55v so that you can get TPS back to 0% and get IACs where they need to be. What is the correct way to do with with no drilling?
I have mine set to 0.55v and my idle air control position is 170 at 145 F engine coolant temp. I should be around 60.
at wot I see 100% TPS at 4.53v
at idle I see 0% TPS at 0.55v
Sure it would be great to adjust the throttle body open until warm idle has a IAC Count of 50. Then reset the TPS by unplugging it and do a key cycle then off and plug it back in. But if you are over 0.55v, this won't reset the TPS % back to 0 for the voltage the TPS Sensor is sending. At 0.65v the TPS % reads 0.4% even after reset.
05-12-2017, 10:01 PM
#2
I sent you a PM.
It's .70V where it reads above the idle limit.
But that limit is 1.2% or so. TPS reset gets you back under it as long as you're under .70V. FWIW, I see 0.4% TPS readings with my TPS set at .59V.
If you go above .70V you have to either clock the TPS or drill a hole.
It's .70V where it reads above the idle limit.
But that limit is 1.2% or so. TPS reset gets you back under it as long as you're under .70V. FWIW, I see 0.4% TPS readings with my TPS set at .59V.
If you go above .70V you have to either clock the TPS or drill a hole.
05-12-2017, 10:26 PM
#3
Thank you for the response.
So Scott is incorrect then in post 13 here?
https://www.hptuners.com/forum/showt...l=1#post239633
I'll get it up to .69v and see where my IAC's are at, then do a TPS reset and hopefully I'll be at 0.4%.
So Scott is incorrect then in post 13 here?
https://www.hptuners.com/forum/showt...l=1#post239633
I'll get it up to .69v and see where my IAC's are at, then do a TPS reset and hopefully I'll be at 0.4%.
05-13-2017, 10:11 AM
#4
It's never been .55V I've ever seen. Maybe for 0.0% it is. But the idle routines will kick on if two things are met: 1) your speed is below the speed set for adaptive idle and 2) your voltage is less than the voltage used by either the follower table (say you have .3g/sec @ 2% TPS... if you are at 2.1% it'll show follower at .3g all the time). And it will keep adaptive idle from kicking in. The other is to make sure your rolling idle maximum TPS is set high enough. I think the default is 1.2% there and if you move it up it may or may not work for adaptive idle. But I've seen 0.8% and still gone into adaptive idle...
05-13-2017, 05:12 PM
#6
That's a ton of spark timing at idle. The MAP reading looks good however @ 850 idle.
Idling at 2.9mv means you're probably still a little rich at idle. But your VE table looks pretty close around 800-1200 cells for 65 kPa. If it's dialed in pretty well, I wouldn't mess with it. But if it's surging at all then you'd need to disable adaptive spark and use the bi-directional controls to lean it out until it'll idle without adaptive spark at all. And your 400 column looks too rich. So if you drop idle down to 500 or 600 you can tell as it'll probably surge like crazy.
Your EOIT settings are still stock. If you want to improve fuel economy, we'd have to mess with that for idle and part throttle fueling. We'd also want a lot less spark timing there. Are you surging on coastdown? Your car never drops below 30 degrees which is an awful lot of spark with a 92mm TB and a large cam.
The other thing would be to enable DFCO for coastdown fuel cutoff. That'll help with fuel economy some too.
One other thing, you can log desired airflow and dynamic airflow and see how far off they are as well as STITs. I would imagine you're 4-5g/sec off desired to dynamic and your STITs may be off until you log desired airflow. But it's not a big deal as long as you're not having any drivability issues if desired and dynamic don't match - you do however want your STITs under 1g/sec off. If you decide to change things, just refer to my PM I sent on adjusting the IAC Effective Area Table and logging the new base airflow as it warms up.
But if it's working fine, then you don't need to mess with it. You just had to open the TB up enough for it to get enough bypass air in there.
Idling at 2.9mv means you're probably still a little rich at idle. But your VE table looks pretty close around 800-1200 cells for 65 kPa. If it's dialed in pretty well, I wouldn't mess with it. But if it's surging at all then you'd need to disable adaptive spark and use the bi-directional controls to lean it out until it'll idle without adaptive spark at all. And your 400 column looks too rich. So if you drop idle down to 500 or 600 you can tell as it'll probably surge like crazy.
Your EOIT settings are still stock. If you want to improve fuel economy, we'd have to mess with that for idle and part throttle fueling. We'd also want a lot less spark timing there. Are you surging on coastdown? Your car never drops below 30 degrees which is an awful lot of spark with a 92mm TB and a large cam.
The other thing would be to enable DFCO for coastdown fuel cutoff. That'll help with fuel economy some too.
One other thing, you can log desired airflow and dynamic airflow and see how far off they are as well as STITs. I would imagine you're 4-5g/sec off desired to dynamic and your STITs may be off until you log desired airflow. But it's not a big deal as long as you're not having any drivability issues if desired and dynamic don't match - you do however want your STITs under 1g/sec off. If you decide to change things, just refer to my PM I sent on adjusting the IAC Effective Area Table and logging the new base airflow as it warms up.
But if it's working fine, then you don't need to mess with it. You just had to open the TB up enough for it to get enough bypass air in there.
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05-16-2017, 10:27 PM
#12
IAC is bouncing around a lot. And lean idle is fine. Leaner is better with a bigger cam.
Reduce your timing to 25 degrees at idle. You have too much in there. Makes it harder for adaptive spark to work. Also, you're probably dumping NOx like a SOB. That probably smells great.
The rest of the changes I'd make are pretty extensive...
Reduce your timing to 25 degrees at idle. You have too much in there. Makes it harder for adaptive spark to work. Also, you're probably dumping NOx like a SOB. That probably smells great.
The rest of the changes I'd make are pretty extensive...