boosted MK1 1.6 ICV Issue
#21
Boost Czar
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your PWM Idle duty is very high (read: fully open) but seems to have little to no effect on the idle speed...
it appears the only thing controlling your idle is: 1. the vacuum leak. 2. your AFRs. 3. your timing.
i still dont see how you can blow off a vacuum line on your wastegate; seems close to impossible. FWIW, your Idle PWM% should be in the low 30's when idling, not high 60s; fix that part of your tune and see what happens, but i doubt that's your issue. I think its mechanical.
it appears the only thing controlling your idle is: 1. the vacuum leak. 2. your AFRs. 3. your timing.
i still dont see how you can blow off a vacuum line on your wastegate; seems close to impossible. FWIW, your Idle PWM% should be in the low 30's when idling, not high 60s; fix that part of your tune and see what happens, but i doubt that's your issue. I think its mechanical.
#22
I have a external actuator located on the top of the manifold, it would seem the vac line leading to it got hot and melted off/blown off haha. I couldn't find the pipe to reattach it to say exactly so replaced it!
So are you thinking there a issue with the ICV itself? Sorry I have only ever messed with the fuel and timing slightly! I got the garage to do my idle, do you have any links I could read up on Braineack?
So are you thinking there a issue with the ICV itself? Sorry I have only ever messed with the fuel and timing slightly! I got the garage to do my idle, do you have any links I could read up on Braineack?
#28
Ive checked for leaks, there isn't any I can fine :(
- TB been replaced with a new gasket n icv
- all vac lines are ok
- rear tb bung is intact
Now the ICV is disconnected it drives ok revs hunt little but driving fine?
any ideas? Anything else I missed?
it does seem to be temperature related? could it be a temp sensor?
- TB been replaced with a new gasket n icv
- all vac lines are ok
- rear tb bung is intact
Now the ICV is disconnected it drives ok revs hunt little but driving fine?
any ideas? Anything else I missed?
it does seem to be temperature related? could it be a temp sensor?
#29
It could be your shitty ******* tune, or I know for a fact it's your shitty tune.
You aren't using closed loop idle, If you can't idle with a fixed idle duty %, your fuel or spark tables are straight garbage. You are still using retarded high idle valve percentages, and you are using a bullshit value for valve frequency for the NA idle valve. It should be 153-186hz, not 300-something.
https://www.miataturbo.net/megasquir...equency-48120/
Tune your car.
You aren't using closed loop idle, If you can't idle with a fixed idle duty %, your fuel or spark tables are straight garbage. You are still using retarded high idle valve percentages, and you are using a bullshit value for valve frequency for the NA idle valve. It should be 153-186hz, not 300-something.
https://www.miataturbo.net/megasquir...equency-48120/
Tune your car.
#30
It could be your shitty ******* tune, or I know for a fact it's your shitty tune.
You aren't using closed loop idle, If you can't idle with a fixed idle duty %, your fuel or spark tables are straight garbage. You are still using retarded high idle valve percentages, and you are using a bullshit value for valve frequency for the NA idle valve. It should be 153-186hz, not 300-something.
https://www.miataturbo.net/megasquir...equency-48120/
Tune your car.
You aren't using closed loop idle, If you can't idle with a fixed idle duty %, your fuel or spark tables are straight garbage. You are still using retarded high idle valve percentages, and you are using a bullshit value for valve frequency for the NA idle valve. It should be 153-186hz, not 300-something.
https://www.miataturbo.net/megasquir...equency-48120/
Tune your car.
Thanks for the info mate I didn't map the car I drop it to a garage on the base map and they sorted out the idle! I will have a look and see what I can do!
Like I said I'm only confused as the car was driving fine till it hit 16psi!!
I understand that you have looked at the map and clearly no more than me so I will take that advice on board and try and sort it!!
I suppose I just want to know why this can happen with no changes being made??
No why it happened will help me understand better that all!
Thanks for you help I will have a look at the tune
#31
See, your big hangup is you think it was ever right. I disagree, I say you barely had it idling stable. 16psi is irrelevant, could have been anything that set off the idle issue.
You need to decrease the idle frequency then adjust the closed loop target valves. Then you can plug the IAC back in and it won't rev to 3K.
https://www.diyautotune.com/support/...ng-megasquirt/
You need to decrease the idle frequency then adjust the closed loop target valves. Then you can plug the IAC back in and it won't rev to 3K.
https://www.diyautotune.com/support/...ng-megasquirt/
#32
See, your big hangup is you think it was ever right. I disagree, I say you barely had it idling stable. 16psi is irrelevant, could have been anything that set off the idle issue.
You need to decrease the idle frequency then adjust the closed loop target valves. Then you can plug the IAC back in and it won't rev to 3K.
https://www.diyautotune.com/support/...ng-megasquirt/
You need to decrease the idle frequency then adjust the closed loop target valves. Then you can plug the IAC back in and it won't rev to 3K.
https://www.diyautotune.com/support/...ng-megasquirt/
Ill read through that idle link and just accordingly, please be patient though as all this is new to me, I have no doubt I'll ask more stupid questions.
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03-12-2014 12:34 PM