CL Boost control PID Failing
 

I have open loop boost working fine, and has been for some time now. I am getting fed up with the changes I get from ambient temps changing. I attempted to get closed loop control dialed in today with no luck. No matter where I put the P term I would overshoot like crazy hitting boost cut.
I have my target boost set for 13psi. This is very upsetting. What am I missing or over looking? I am using DIY's solenoid hooked up to my Tial 38mm using both ports according to their diagram on the website.

start with P at 200 and I/D both at 0.

You should be no where close to your close loop targets, you should be still at wastegate. If this is not the case, do not continue and come back and post a screen caputre of your boost control settings.

If this is the case, continue.

Keep lowering P until you breech your boost target in the closed loop table. Use 2nd gear and only try to spool the turbo, no need to run to redline.

Once you reach your target, you will increase the I term from 0 to help keep the boost holding to redline. The more I term you add, you might need to add a bit of P term back as well. Increase I until you hold your closed loop target to redline.

If (and it will) the boost oscillates, add D term to smooth it out and remove any boost overshoot you might have while spooling up.


Now post more pics of your GnarBar and explain wtf the point of that all is...

I did try starting with proportional at 200 and the rest 0'd out. Not sure where I missed something.

As for my bar, I know because of the design it wouldn't be o.k. to use competitively. To go out with the local porsche, alfa, bmw, etc. clubs it is fine. I dont mind as this is my daily driver. I have no doubts of it keeping my alive in a roll over. The hoop goes all the way to the floor where the base is boxed to the sill and rear wall. There are a few other pics in my intro thread too.

how to you see out of your rear view? That bar is so odd to me, all the extra bracing looks absolutely pointless. Also, are those little rods supossed to be harness bars? like why not use, i dunno, the harness bar?

anyways, for now, make the closed loop table above 65% TPS 190kPa, and use the 39.5Hz rate.

If you run with the settings as is, will you overboost? you should be just making wastegate at the moment.

And just to confirm, you have PA0 running to boost OUT, then boost OUT running to your db15 on pin X, then from Pin X on your db15 pigtail that's running directly to you boost solenoid, where the second wire on your boost solenoid is run directly to 12v?

also can you post a pic of how your solenoid is plumbed to the wastegate?

yep. overboost to roughly 16-17psi when it hits cut. It is a real pain. Ambient temp changed from 95 yesterday to 60's today.

Bar: I can see out the rear view fine. Probably better then cars with an X right there. The harness bar is used for the harnesses. Fab guy didn't want to use traditional tiny harness "locators" so he made those out of bar stock he had laying around. I love it, nobody else has one remotely close, and it tightened up the car a bit. Ive been told by a few how "bad" and "useless" the bar is by the interwebz racers. I've heard it all. I don't care what other people think. If people come check it out in person and can explain what makes it so horrible or pointless then I would be more interested

answer the rest of my jimity-junk.

Absolutely

Side port of the wastegate is running to the T from the boost source before the TB and runs to the top port of the DIY solenoid.
The top(bottom) port of the wastegate is plumbed directly to the port on the solenoid seen in the pic. Pin PA0 on my DB15 and the 12v in the bay is where I have it wired up to.

ah external wastegate changes things. i have to think for a minute.

I just got back from some testing with loads of fail. I decided to try it hooked up like an internally gated /single port EWG setup with the boost source feeding into the lower port of the solenoid and the out port feeding the side of the wastegate with nothing connected to the top of it. Still over boosting.

on solenoid: lower port should go to boost source, single side exhaust to wastegate.

ewg: try lower port only for now.

That's how I last had it in my previous drive. Going to change to the top port on the wg this time though.

Still no luck with closed loop. Won't be able to test out much until Sunday.