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Calibra Turbo

Started by Tcal, November 06, 2007, 11:08:30 AM

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Tcal

i did try to fix that stalling problem again. I did again notice that when IAT is near 10c it wonÃ,´t happen, but when it heatsoaks and starts to show something like 25 then im having those problems again.
It doesnÃ,´t have much difference if i blip throttle like 3% or 30%. Then revs drop near 600-700 and then recovers...
Okay, if i put larger value to idle PID ref table, it helps a bit.
But when IAT gets colder like -5degrees,  idle goes too up because of that larger value in that  table.
I did try that PID controller too again, didnÃ,´t have enough motivation with it.
Maybe iÃ,´m stupid with this but does that do same even if PID is setted ok, because of that heatsoaking??

IAC DC is near 53 when warm engine and cold weather and idle is much smoother too...
IAC DC is near 56 when warm engine and warm weather/heatsoaked IAT

[email protected]

Are you adjusting the values in: Extras->Idle PID Ref table, PWM

Rob

Tcal


[email protected]

So you're saying the heat of the IAT is effecting your idle?  Have you turned the MAT dependent retard off ( Settings->Constants )
The PID should work across temperature ranges though.

Tcal

I have fake airdensity 98 in Megatune.

[email protected]

Thats for barometric correction, shouldn't effect anything.

Tcal

 :o
I havenÃ,´t even noticed those new options. ;D but now i see them, they are both enabled.. 

MWfire

I have same problem on my opel 2.0. When the iac is cold, 39% DC is enough for 1200rpms, but when is hot(iac) i need 47%DC for 1000rpm. I can see that map is changing when is fuel off and 2000rpm. Hotter iac and map is lower. I think my iac is broken(I did some cleanig and now is better).

Tcal

I was wondering about that, i have now all banks firing when cranking. If i change it to alternate iÃ,´ll have to multiply those cranking pulses, correct?

[email protected]

Yes, you'll be getting around 1/4 the amount of fuel going from all banks to alternating.

Tcal

Added some pics and stuff to first message...

Tcal

#41
I've been playing with idle quite a lot.
When iat is at 5, iac dc is 52-53. And iat at 30-40 then that dc is 58-59.
If i set that ref point to 53, cold iat idle works perfectly. With this setup warm iat idle is not good. (rpms drop too low after revving because idle valve waits at too small position, revs usually recover after this dip)
If i set that ref point to 56, it cures those warm problems, (hot startup ase idle, idle after revving) but with this, cold iat idle stays at 1700-1900 rpm and iac dc stays in that 56.
Why does it do this.?

Idle adv controller is on.
And idle pid too. And this pid thing is the bugger i've been playing with.
If setting those inc/dec values big enough, idle starts to oscillate..

And yes i've tried a lot of different PID values.

sorry if this is too messy to read. I have to write this through my phone. For some reason my pc's isp provider doesn't allow me to enter this site.

Edit: i've found in wiki that Peter Jensen added an diode between those iac valve wirings. Could this be the answer to my problems.?

Tcal

I Added a diode between iac valve wires.
It behaves better now. I did drove it about half an hour... It idled fine. Even if ref value was 56 or 57.

Next question is, will that diode do any harm to ecu or so when fitted like that ?   

Tcal

I Added a diode between iac valve wires.
It behaves better now. I did drove it about half an hour... It idled fine. Even if ref value was 56 or 57.

Next question is, will that diode do any harm to ecu or so when fitted like that ?   

[email protected]

That diode is acting as an auxillary flyback diode.  It will not hurt the injectors as its in a different circuit - and its a good solution, there must be a lot of voltage dumped back when a low resistance solenoid discharges...
What sort of resistance is the IACV solenoid?