I am extremely green at this megasquirt stuff but i have got the car running and it was idling fair but as soon as you hit throttle it starts cutting up real bad and pegs the afr gauge lean but if you move the throttle on past that point it will clear up, its at around 10% on tps is the problem area. The car is a 93 mustang 302 with dart pro1 heads and e or f cam not 100% on that, holley systemax intake, FIC 74lb injectors, 76 mm on3 turbo kit with intercooler. Here is data log of said problem. Any guidance in the right direction would greatly appreciated.
Megasquirt PNP2 turbo foxbody dead spot at partial throttle.
- Thread starter jcm_us
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Ok lets start from the top..
The tune needs to be cleaned up significantly, the AFR table makes little sense it needs to be flatter in the idle range you should look at some of the tunes I have helped people with to get an idea of what is normal. Your VE table needs work mainly because looking at the datalog I can see that when you raise the RPM it goes full lean the WB reads 19AFR nothing will want to run at this AFR unless its maybe a direct injection engine. You will have to manually add fuel in this area, if you are trying to rely on autotune to fix it dont.... autotune works very well but when the AFR is "out of range" then it will ignore the input as it may be erroneous data.
Your Ign table is far too aggressive in the decel [low KPA] areas and I am not sure why you are trying to command 0 degrees at the top of the RPM range.. If you want to cut spark do it in the Rev limiter section under general settings. A word of advice, the MS only commands the advance value it cannot cut spark on a TFI vehicle because the TFI is what fires the coil. When the MS tries to cut spark the TFI just fires at the mechanical advance like you pulled the spout You cannot command a value lower than the offset value either. As an example if you were to have a base offset of 10* and command 0* it will just fire at 10*
The tune needs to be cleaned up significantly, the AFR table makes little sense it needs to be flatter in the idle range you should look at some of the tunes I have helped people with to get an idea of what is normal. Your VE table needs work mainly because looking at the datalog I can see that when you raise the RPM it goes full lean the WB reads 19AFR nothing will want to run at this AFR unless its maybe a direct injection engine. You will have to manually add fuel in this area, if you are trying to rely on autotune to fix it dont.... autotune works very well but when the AFR is "out of range" then it will ignore the input as it may be erroneous data.
Your Ign table is far too aggressive in the decel [low KPA] areas and I am not sure why you are trying to command 0 degrees at the top of the RPM range.. If you want to cut spark do it in the Rev limiter section under general settings. A word of advice, the MS only commands the advance value it cannot cut spark on a TFI vehicle because the TFI is what fires the coil. When the MS tries to cut spark the TFI just fires at the mechanical advance like you pulled the spout You cannot command a value lower than the offset value either. As an example if you were to have a base offset of 10* and command 0* it will just fire at 10*
I loaded all new afr, ve, and spark tables that I believe to be more accurate as they came from someone with a similar setup as mine that you helped. The car does the exact same thing at about 15-20% throttle i really dont think the ve tables are the problem because it will do this at any rpm or kpa if you get into that section of the throttle. This is making me think it is something else on the car like maybe the tps but the tps doesnt do anything crazy on the gauge in TS. The pulse width kind of hesitates when it does this but I am stumped at this point. One other thing when you pull up the time based accel enrich chart the map graph jumps around a lot with the key on and the car not running but if you look at the kpa gauge on the main page it on moves between 98.1-98.3 but on the ae chart looks like its jumping everywhere. The last thing i am not sure if my injector dead time is set right or not i will include info on injectors, latest tune and data log. TIA any and all help will be appreciated. This thing already has me about to pull my hair out, but trying to be patient with it.
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NO, you simply have to tune the VE table, your datalog shows the engine going full lean when you blip the throttle. if its lean add fuel [bigger numbers in the VE table].
If you are attempting to use autotune it will do nothing to adjust when you just stab the throttle over and over, its filtering that data because its a transient condition. you need to bring the rpm up slow and steady and let autotune do its job while you add or subtract fuel manually to make blanket adjustments.
I can help you get the car running and idling if you like visit my services page or PM for details
If you are attempting to use autotune it will do nothing to adjust when you just stab the throttle over and over, its filtering that data because its a transient condition. you need to bring the rpm up slow and steady and let autotune do its job while you add or subtract fuel manually to make blanket adjustments.
I can help you get the car running and idling if you like visit my services page or PM for details
I added a ton of fuel manually in that area of the be chart not with autotune I changed the numbers from like 30s to 70s with no change but I’ll add more I guess but that seems odd that it does this at any kpa or rpm if I return to that throttle position
