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Lean issues

Old 12-24-2007, 01:28 PM
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Default Lean issues

Ok im getting REALLy pissed

I started off with the PNP base map which was very very rich... i just am tuning low rpms no load right now (basicly idle) and as soon as i get it to about 14.5 and steady itll slowly just climb to 100% lean and the motor will die. Its like the only way to make the motor run nice is leave it at 12:1

My acceleration wizard is off... AFR target tables are off, and so i sego correction. idk wtf is causing this but its really anoying.

Im using a PLX wideband with all the correct settings

One more thing, with the Ego steps set to 0 it still says 100% ego correction in the VE tuning window...does that mean something?
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Old 12-24-2007, 01:31 PM
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100% means no correction. or 100% of your fuel. 98 x 1 = 98.
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Old 12-24-2007, 02:08 PM
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ok next question.... why is it staying in warmup at 150%... 150 is at -40*F... wtf is it reading there for
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Old 12-24-2007, 02:25 PM
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You should post your MSQ. It's a real PITA trouble shooting someone elses mess when you don't know what they're working with. You'll have to host it somewhere i guess since you're not a supporting member though.
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Old 12-24-2007, 02:34 PM
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stock mspnp msq for a 94 or 95... only thing changed is overrun is turned off along with acceleration wizard off

http://www.megasquirtpnp.com/models/...Map_101007.msq

The issue is the warmup staying at like 150%...
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Old 12-24-2007, 02:40 PM
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I take it you're tuning at idle and this is occuring. If it's getting leaner at idle I bet your IAT sensor is heat soaking causing it to lean out. You can add fuel by going to advanced-> coolant related air density, then options and changing it to IAT related air density. This will allow you to add fuel as the sensor heat soaks. Then set the RPM values so that it is only active at idle. For example, set it to be disabled after 1600-1800 RPM.
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Old 12-24-2007, 02:44 PM
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how would my IAT sensor be heat soaking... its just in the stock intake tube (im NA btw).

Although it does read too high i think (stock gm sensor and settings)...it read up to like 150* when im NA and its 50* outside

But more importantly, what is wrong with the warmup crap that is making it stay in warmup mode. When i first open up warmup wizard an arrow flashes at -40*F
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Old 12-24-2007, 04:27 PM
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anyoneeee???? i need warmup help!
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Old 12-24-2007, 04:31 PM
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what does you CLT and AIT normally read when the thing has been sitting overnight? are they close to ambient? are they close to each other? they are a very important equation in the fuel mix, so if the values arent close neither will your fueling.
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Old 12-24-2007, 04:35 PM
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ill double check, but i believe that the IAT reads high at initial start up... like 50 when its 35 out. the coolant seems very accurate once it gets going but if i remember correctly its a little high at initial start up also


i still really need to know why warmup is staying above 100% tho even when my coolant is 170*F ...this is with the warmup settings given by the stock PNP map
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Old 12-24-2007, 04:59 PM
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yup it said it was 73 degrees when the car has been off for 2 hours and its 40 out.... coolant is very accurate. My warmup seems to be working now?!

so the question now is... why did the GM defults not work for my IAT sensor. do the closed and open sensors have different values because i bought the open element sensor so i can use it once im boosted
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Old 12-24-2007, 05:08 PM
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did you make sure it was C and not F when you flashed it, or vise versa?
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Old 12-24-2007, 05:17 PM
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yes... i tripple checked everything many many times. I guess i can remove the sensor and find my own values?

so my warmup works fine...
But still... every time i pass 14:1 afr it just jumps down to lean and stalls out..or if i m driving and tune up to about 14:1 itll just go lean and not want to drive

WHYYYYYYYYYYYYY
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Old 12-24-2007, 05:26 PM
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during warmup it should be 13.5:1-12:1 tune your values to see that until 160* CLT
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Old 12-24-2007, 05:36 PM
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OK this blows... here is a summary of what is going on:

-IAT sensor seems to be off...reading too hot
-Warmup enrichments work fine...until coolant temp reaches over 160 and/or IAT over 100 (not sure wat is affecting it... and yes ik that IAT is an incorrect reading)... at this point an arrow doesnt show up anymore and it just puts the enrichment strait to 150%
-Engine goes lean and/or stalls as soon as u tune leaner than 14:1

Facts:
-GM IAT sensor with GM defults from easytherm
-stock CLT sensor working perfectly... good values
-Stock PNP 94-95 map with accel turned off and ego+target maps off
-Code set up for PLX wideband and MSnS_extra
-stock engine/injectors

HELP MEEE I WANT TO TUNE!
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Old 12-24-2007, 05:41 PM
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Your IAT sensor is heatsoaking. It doesn't matter if your're NA or blown with a jet engine. The sensor is heat soaking just sitting there at idle. Go for a drive and see if it cools down with air rushing over it. Saml01 had the same problem in his stock intake tube. The GM defaults work perfect, that's not your problem.

If you think's it's wrong then make up a glass of ice water and take it outside with you. Pull the sensor and put it in the water. Should be close to around 34* F.
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Old 12-24-2007, 07:13 PM
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It is your IAT sensor heat soaking as people have said. I had the same problem with mine when I was running around na during the summer. The stock intake tubing does not do a good job of getting cool air. With your car just sitting there you quickly start to pick up warmer and warmer air that is in your engine bay. I will try to post up my settings for IAT correction that I was using during the summer later tonight.
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Old 12-24-2007, 08:52 PM
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Code:
20	111
50	100
80	100
85	105
90	115
100	130
120	150
my sensor heatsoak out the waazoo, those are my AIT correction values.
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Old 12-24-2007, 09:14 PM
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thanks a lot guys, merry xmas!!!! ill put in the new values 2morro


As for my other 2 problems... why do u think the warmup enrichments go nuts after the car is at full temp?? and why cant i tune to stoch without it just climbing to lean and stalling?
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Old 12-24-2007, 11:10 PM
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Originally Posted by 240_to_miata_OWNER
ill double check, but i believe that the IAT reads high at initial start up... like 50 when its 35 out. the coolant seems very accurate once it gets going but if i remember correctly its a little high at initial start up also
...
yup it said it was 73 degrees when the car has been off for 2 hours and its 40 out.... coolant is very accurate. My warmup seems to be working now?!

so the question now is... why did the GM defults not work for my IAT sensor.
Originally Posted by Braineack
did you make sure it was C and not F when you flashed it, or vise versa?
Yeah - I had the same thing - hadn't run the car in days, and the AIT sensor read significantly warmer than the coolant. Like, it said something like 80 degrees when it was more like 65. Not a huge difference.


Strangely, I can't get my car not to idle. I can get it to idle uneven, but even when my wideband reads 16.0:1 it'll sit there and happily idle along at like 550 rpm with the IAC closed and the throttle against the stop. I was trying to pick a good amount of fuel for idle, but it just kinda doesn't seem to matter. Richer than maybe 13.0:1 and it doesn't idle as well.
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