This helped my idle a lot
#1
Junior Member
Thread Starter
iTrader: (10)
Join Date: Jan 2008
Location: SF Bay Area
Posts: 291
Total Cats: 0
This helped my idle a lot
My car idled perfectly first thing in the morning, but got heatsoaked and idled crazy lean anytime I stopped. Sound familiar?
Searching around I found some very informative posts on Hot IAT Idle like this one. So I messed with the "IAT Corrected" setting in the "Coolant Related Air Density settings" menu but the correction seemed to be linked only to the coolant temperature.
Finally I found this thread on the msextra board that fixed the problem.
Basically, open up the msns-extra.ini file and find this bit of code:
Change xBins line to read:
Now corrections are linked to IAT as opposed to CLT.
So far so good. Sensor still heat soaks, but I'm able to compensate to maintain a good afr.
Hopefully this helps someone.
Searching around I found some very informative posts on Hot IAT Idle like this one. So I messed with the "IAT Corrected" setting in the "Coolant Related Air Density settings" menu but the correction seemed to be linked only to the coolant temperature.
Finally I found this thread on the msextra board that fixed the problem.
Basically, open up the msns-extra.ini file and find this bit of code:
[CurveEditor]
curve = clt_IATCorrC, "Coolant corrected Air Density, see Settings", 9
topicHelp = airdenHelp
columnLabel = "Temp", "Offset"
xBins = IATCTemp, coolant
yBins = IATCorS
gauge = matGauge
#if CELSIUS
xAxis = -40, 100, 15
#else
xAxis = -40, 220, 14
#endif
yAxis = 50, 150, 11
curve = clt_IATCorrC, "Coolant corrected Air Density, see Settings", 9
topicHelp = airdenHelp
columnLabel = "Temp", "Offset"
xBins = IATCTemp, coolant
yBins = IATCorS
gauge = matGauge
#if CELSIUS
xAxis = -40, 100, 15
#else
xAxis = -40, 220, 14
#endif
yAxis = 50, 150, 11
xBins = IATCTemp, mat
So far so good. Sensor still heat soaks, but I'm able to compensate to maintain a good afr.
Hopefully this helps someone.
#3
I've got the same issue except the IAT readings really do not increase drastically which is weird. If I go shopping and come back to start the car within 15 minutes or so the IAT reading is only up maybe a couple degrees but the AFRs will be off the charts lean for the first minute or so of driving. I've tried shielding the pipe until I have time to move the sensor but that didn't help and it seems like the IAT temp should have to increase much more than it does to produce the lean idle?
#4
I've got the same issue except the IAT readings really do not increase drastically which is weird. If I go shopping and come back to start the car within 15 minutes or so the IAT reading is only up maybe a couple degrees but the AFRs will be off the charts lean for the first minute or so of driving. I've tried shielding the pipe until I have time to move the sensor but that didn't help and it seems like the IAT temp should have to increase much more than it does to produce the lean idle?
#5
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,729
Total Cats: 4,126
The option for AIT corrections is part of the standard code, just go to advanced options and select it. That's all you did, but you did it the backdoor, nerdy programmer way. I'm certain 90% of here already use it.
It's been discussed here in depth. The MSPNP map unitizes this table as shipped. Easiest solution to the problem is moving the AIT sensor out of the engine bay. However, with corrections I never really had an issue.
It's been discussed here in depth. The MSPNP map unitizes this table as shipped. Easiest solution to the problem is moving the AIT sensor out of the engine bay. However, with corrections I never really had an issue.
#8
Junior Member
Thread Starter
iTrader: (10)
Join Date: Jan 2008
Location: SF Bay Area
Posts: 291
Total Cats: 0
Well, Even when I changed the "Correction based on:" to "IAT corrected", the corrections still seemed to be CLT based. Only when I made the changes to the ini file did it work properly.
My idle is awesome now.
YMMV
My idle is awesome now.
YMMV
#9
I had this problem on one of my turbo datsun's. The AIT corrections helped but did not fix the problem. It only made megasquirt not change the pulse width as much. I was still seeing way too high IATs which took 20-30 seconds to get back down to correct temp. Which by then the 1/4 mile was over. My problem was the IAT was behind the radiator. I moved it closer to IC outlet and infront of the radiator and it was completely gone.
#10
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,729
Total Cats: 4,126
weird, ill take a look at my .ini file next time just to see if mines correct, but the corrections always worked for me, as i was seeing over 120*F intake temps on a warm day. Now my AIT remains ambient and i don't even use corrections.
#12
Junior Member
Thread Starter
iTrader: (10)
Join Date: Jan 2008
Location: SF Bay Area
Posts: 291
Total Cats: 0
It seems strange to me that the MSPNP base msq, corrections are turned off by default. I can understand you'd probably want it off during tuning, but I'm surprised the DIY install guide doesn't mention IAT corrections at all. I suspect most of the BEGi and probably other kits too, have the IAT mounted where heatsoak will be a problem.
I'll probably move the sensor eventually but this has solved my problem for now.
Before I made this change, I felt like a fool having to rev the motor just to keep it running.
I'll probably move the sensor eventually but this has solved my problem for now.
Before I made this change, I felt like a fool having to rev the motor just to keep it running.
Thread
Thread Starter
Forum
Replies
Last Post
StratoBlue1109
Miata parts for sale/trade
21
09-30-2018 01:09 PM