mspnp 550cc w/out afm,wont start
#1
mspnp 550cc w/out afm,wont start
i install my pnp on 92 miata stock and no problem starting,when eliminate my afm and install my new 550cc injector car wont start,i change req fuel and automatically set to 5.1 on req fuel,is this correct or not pls help,and what should i put on injector opening time (ms).? injector staging? batt voltage (ms/v)?
pwm current limit(%)? pwm time threshold(ms)??fast idle threshold?? pls help.
pwm current limit(%)? pwm time threshold(ms)??fast idle threshold?? pls help.
#6
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Is your engine flooded? Pull a plug and check.
Is your wiring modified in any way? Your sig shows you had an emanage at one point.
Connect your laptop and watch the gauges in megatune.
Look for manifold air temp, rpm, injector pulsewidth, etc.
Is your wiring modified in any way? Your sig shows you had an emanage at one point.
Connect your laptop and watch the gauges in megatune.
Look for manifold air temp, rpm, injector pulsewidth, etc.
#18
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Is the car is a nice quiet place? With the key in the off position, turn it to the ON position but not all the way to start, you should hear the fuel pump come on for two seconds, and then you'll hear it turn off. Usually you can hear the click of the relay as it turns on and off. You can do this again and again (if you have trouble hearing it the first time) to make sure the fuel pump is working... That's the first step.
With the AFM in place the fuel pump relay will get jumpered on by the AFM regardless of what the MSPNP tells it to do. With the AFM removed it relies on the MSPNP to prime the pump and then to activate it when you crank it. It's possible if a step was skipped in the install that it may not be commanding the FP to activate once you remove the AFM.
Did you try it with the AFM removed before you swapped in the 550's? That would have been ideal so you'd know if the problem was the AFM removal or the larger injectors. If it's the injectors it's just a tuning thing...
You mentioned you changed your REQ_FUEL... that's only part of what you need to change for larger injectors. It's important, but only after you get it running. If you didn't change your cranking pulsewidths you'll never get it to start in the first place with injectors that much larger than stock. It will flood in an instant. Also you'll need to change your AE PW's. All of this is covered in the manual.
Check this stuff out and let me know if I can assist!
With the AFM in place the fuel pump relay will get jumpered on by the AFM regardless of what the MSPNP tells it to do. With the AFM removed it relies on the MSPNP to prime the pump and then to activate it when you crank it. It's possible if a step was skipped in the install that it may not be commanding the FP to activate once you remove the AFM.
Did you try it with the AFM removed before you swapped in the 550's? That would have been ideal so you'd know if the problem was the AFM removal or the larger injectors. If it's the injectors it's just a tuning thing...
You mentioned you changed your REQ_FUEL... that's only part of what you need to change for larger injectors. It's important, but only after you get it running. If you didn't change your cranking pulsewidths you'll never get it to start in the first place with injectors that much larger than stock. It will flood in an instant. Also you'll need to change your AE PW's. All of this is covered in the manual.
Check this stuff out and let me know if I can assist!
__________________
Jerry a.k.a. 'FoundSoul'
DIYAutoTune.com
'91 Miata BEGi S3 GT2560 w/ MSPNP - 14.1psi - 253whp, 232wtq
'95 Miata n/a
A few other cars....
Jerry a.k.a. 'FoundSoul'
DIYAutoTune.com
'91 Miata BEGi S3 GT2560 w/ MSPNP - 14.1psi - 253whp, 232wtq
'95 Miata n/a
A few other cars....
#19
Is the car is a nice quiet place? With the key in the off position, turn it to the ON position but not all the way to start, you should hear the fuel pump come on for two seconds, and then you'll hear it turn off. Usually you can hear the click of the relay as it turns on and off. You can do this again and again (if you have trouble hearing it the first time) to make sure the fuel pump is working... That's the first step.
With the AFM in place the fuel pump relay will get jumpered on by the AFM regardless of what the MSPNP tells it to do. With the AFM removed it relies on the MSPNP to prime the pump and then to activate it when you crank it. It's possible if a step was skipped in the install that it may not be commanding the FP to activate once you remove the AFM.
Did you try it with the AFM removed before you swapped in the 550's? That would have been ideal so you'd know if the problem was the AFM removal or the larger injectors. If it's the injectors it's just a tuning thing...
You mentioned you changed your REQ_FUEL... that's only part of what you need to change for larger injectors. It's important, but only after you get it running. If you didn't change your cranking pulsewidths you'll never get it to start in the first place with injectors that much larger than stock. It will flood in an instant. Also you'll need to change your AE PW's. All of this is covered in the manual.
Check this stuff out and let me know if I can assist!
With the AFM in place the fuel pump relay will get jumpered on by the AFM regardless of what the MSPNP tells it to do. With the AFM removed it relies on the MSPNP to prime the pump and then to activate it when you crank it. It's possible if a step was skipped in the install that it may not be commanding the FP to activate once you remove the AFM.
Did you try it with the AFM removed before you swapped in the 550's? That would have been ideal so you'd know if the problem was the AFM removal or the larger injectors. If it's the injectors it's just a tuning thing...
You mentioned you changed your REQ_FUEL... that's only part of what you need to change for larger injectors. It's important, but only after you get it running. If you didn't change your cranking pulsewidths you'll never get it to start in the first place with injectors that much larger than stock. It will flood in an instant. Also you'll need to change your AE PW's. All of this is covered in the manual.
Check this stuff out and let me know if I can assist!
Last edited by castillejos2000; 06-04-2007 at 04:58 PM.
#20
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Have you adjusted your cranking pulsewidths and accell enrichments to get them close based on the new injectors? I'd do this first, and it is covered in the manual.
Then disable EGO Correction before you tune: BASIC SETTINGS: EXHAUST GAS SETTINGS (Set Controller Step Size to 0). After tuning set it back to 1.
Also disable Accelleration Enrichment: BASIC SETTINGS: ACCELERATION WIZARD (Set MAPDot Threshold to 500 or something really high). After tuning set it back to 50.
Have a qualified tuner dial it in on a steady state dyno. Loading it into each cell and tuning fuel first, and then doing the same tuning ignition, finally tuning higher throttle doing ramp runs on up to WOT ramp runs. That's my preferred method anyways, your mileage may vary. After dyno tuning you can re-enable EGO correction and Accelleration Enrichments and fine tune the Accell Enrichments if they need it. Cranking PW, Warmup Enrichments, and AfterStart Enrichments could need fine tuning as well though they are probably close enough to serve you pretty well without adjustment.
Lastly is cruise tuning, which they may have been able to hit on the dyno or may not have been able to. It's sometimes easier to do while actually cruising with the actual load you'll have on the car in a real life cruise situation. You'll be looking for good gas mileage and driveability here.
Then disable EGO Correction before you tune: BASIC SETTINGS: EXHAUST GAS SETTINGS (Set Controller Step Size to 0). After tuning set it back to 1.
Also disable Accelleration Enrichment: BASIC SETTINGS: ACCELERATION WIZARD (Set MAPDot Threshold to 500 or something really high). After tuning set it back to 50.
Have a qualified tuner dial it in on a steady state dyno. Loading it into each cell and tuning fuel first, and then doing the same tuning ignition, finally tuning higher throttle doing ramp runs on up to WOT ramp runs. That's my preferred method anyways, your mileage may vary. After dyno tuning you can re-enable EGO correction and Accelleration Enrichments and fine tune the Accell Enrichments if they need it. Cranking PW, Warmup Enrichments, and AfterStart Enrichments could need fine tuning as well though they are probably close enough to serve you pretty well without adjustment.
Lastly is cruise tuning, which they may have been able to hit on the dyno or may not have been able to. It's sometimes easier to do while actually cruising with the actual load you'll have on the car in a real life cruise situation. You'll be looking for good gas mileage and driveability here.
__________________
Jerry a.k.a. 'FoundSoul'
DIYAutoTune.com
'91 Miata BEGi S3 GT2560 w/ MSPNP - 14.1psi - 253whp, 232wtq
'95 Miata n/a
A few other cars....
Jerry a.k.a. 'FoundSoul'
DIYAutoTune.com
'91 Miata BEGi S3 GT2560 w/ MSPNP - 14.1psi - 253whp, 232wtq
'95 Miata n/a
A few other cars....