PowerFC cutout issue

[Trondelond]

I uploaded the standard map to my PFC last night to use as a base for tuning, as this is a lot smoother and hopefully a better starting point than the one previous tuners have come up with.
Set the injectors to 73% and Z32. It's running quite rich on idle still, but that should be easily fixed.

Drove along, and AFR's seem perfectly fine under light load. But - when I gave it a tiny bit of stick, there was a massive cutout as soon as I hit 0.8 bar. I THINK it's 0.8 bar that triggers it, not RPM.

I'm using a 3071 with an actuator that I don't know the "base pressure" of. But I did set the PFC's boost control kit to 0.5 bar. I'm wondering if this could be the problem - when the actuator reaches operating pressure, and the controller is set to 0.5 bar, it just cuts out?

Or am I missing something else entirely here?

 

[campbellju]

Assuming you have the PFC boost controller kit installed and enabled then the PFC will ignition cut when you go >0.1bar above the target setting. It feels like you've hit a wall.

This is one of the reasons why I prefer an integrated ECU and don't like piggy backs as you get better fault control.

Set the target boost setting to the same or just above your actuator and leave the duty around 40 to avoid overboost. You can tune your duty setting later.

Don't diable your boost controller though as the car will overboost to 2.0Bar ;-)

 

[Trondelond]

Assuming you have the PFC boost controller kit installed and enabled then the PFC will ignition cut when you go >0.1bar above the target setting. It feels like you've hit a wall.

This is one of the reasons why I prefer an integrated ECU and don't like piggy backs as you get better fault control.

Set the target boost setting to the same or just above your actuator and leave the duty around 40 to avoid overboost. You can tune your duty setting later.

Don't diable your boost controller though as the car will overboost to 2.0Bar ;-)

Heh.. I was hoping you were online.. :lol:

I had it set to 0.5 bar as you can see in the picture, and it's the PFC boost controller kit I have, yes. I'll just try and set it at 0.85 or something then, and see if the brick wall has been removed! Thanks!

 

[Trip]

The way I see it: The boost controller cannot limit boost. The lower limit is always set on the actuator.

So if the actuator is for instance 0.9bar and the boost controller is set to 0.5bar. the car will boost to 0.9bar.. In this instance the Power FC will sense more boost then it was set at and will cut ignition to prevent overboost.


Ideally you set the Power Fc slightly above the actuator settings


Edit: when i say limit's boost. I mean by lowering boost below actuator spring rate.

 

[Trondelond]

Thanks Trip, that's what I was thinking when it happened as well. Or - rather HOPING that was the problem.

 

[Trondelond]

Ok- so now I've set the boost to 0.85bar, and the cutting is gone. But it kept going up to 1.0 bar before I stepped off the throttle.
Paying attention to the boost gauge, A/F gauge AND the road was getting difficult.

Anyone know what sort of base pressure PaulB's 3071 was? I never got a reply from him.

 

[Trip]

best way to find out is to bypass the boost soleniod and connect the actuator direct to a vacuum feed. Go for a drive and see what is the max boost. Keep an eye on those AFR's and boost gauge

 

[Trondelond]

That's pretty scary on an unmapped car! But I suppose I'll have to do that.
Only thing I'm wondering - the compressor housing was impossible to rotate so that the actuator arm was pointing straight out from the actuator (while clearing the manifold).
Could this be a problem?

 

[Trip]

That's pretty scary on an unmapped car! But I suppose I'll have to do that.
Only thing I'm wondering - the compressor housing was impossible to rotate so that the actuator arm was pointing straight out from the actuator (while clearing the manifold).
Could this be a problem?

If you have an air compressor with an adjustable pressure nozzle, set it to 1bar and conenct it to the actuator. with your naked eyes see if the rod is moving. If it doesn't repeat slowly add more pressure until it opens.

I did this with turbo out of the car so it was easy to identify when the rod starts moving

 

[Trondelond]

If you have an air compressor with an adjustable pressure nozzle, set it to 1bar and conenct it to the actuator. with your naked eyes see if the rod is moving. If it doesn't repeat slowly add more pressure until it opens.

I did this with turbo out of the car so it was easy to identify when the rod starts moving

Unfortunately I don't have one, so I may have to pop by some garage to see if they might be able to help. Unless someone on here knows PaulB and can get it out of him.