Boost control issues with solenoid... HELP!!

sohcd16y8 · Post by **sohcd16y8** » Mon Mar 09, 2009 7:42 pm

Alright guys, I have been using eCtune for over a year now and have been running the Solenoid for about 5 months. Up until now it has been extremely consistent and worked flawlessly. Two days ago I was on a long (roughyly 3 hours of driving) cruise doing quite a few pulls. It was fine for about the first 2.5 hours. then out of nowhere, I did a pull and it his boost cut, then another, then another. This was on High Boost (20 psi) using boost by gear. I pulled out the computer and hooked it up and started to play with it, but I could not get it to calm down. I then noticed that the lower boost (17psi) was spiking, but then eventually coming back down. With the boost controller off and on wastegate only it was perfectly fine on the gated 15 psi. I went out today to try and figure it out, but it was the same old story. I have attached the map with the boost solenoid settings exactly how they have been for the past five months without a problem. Here is a break down of the logs. Log 1 Pull 1 - BC on, low boost 17psi, everything seems normal here, it spikes a bit but the closed loop bring it down just fine. It does however seem to need an excessive amount of duty cycle pulled. In the past it would be at 17 psi at 18% duty cycle dead on. Pull 2 - Same thing Pull 3 - EBC on, high boost 20 psi, the boost is spiking and hit boost cut. NOW here is my question, why is the closed loop adding in duty cycle when the actual psi is above target? Pull 4 - Same as 3 Log 2: Pull 1 (about 20 seconds in) - same story, high boost, spikes hard, closed loop adding in duty cycle Pull 2 - Wastegate only, everything normal Pull 3 - Same as 2 Pull 4 - Low boost, spikes up, THIS time however, as opposed to the other 17 psi pulls the closed loop adds in duty cycle till it spikes to 21 psi and then brings down the duty cycle and the boost levels under control. Pull 5 - Everything good, 17psi Pull 6 - High boost, spike, closed loop adds, boost cut Pull 7 - High boost, spike, closed loop adding, UNTIL then very end where the closed loop starts to pull back on duty cycle buit it still hits the cut Log 3: Pull 1 - Duty cycle now fixed to 20%, runs up to roughly 21 psi and seems stable. This is odd though, since up until these issues it took 28% to hit 20 psi. Pull 2 - Same as pull 1, but this times hits 22 psi. Pull 3 - Wastegate only, everything normal So my questions are: 1. Any idea what could cause everythign to go from perfectly fine, to this shinanigans out of nowhere? 2. Why is the closed loop adding in duty cycle when the actual psi level exceeds the target? 3. Why does it the closed loop act totally normal some times, others takes a while to bring down the duty cycle, and other times just keep adding in DC? 4. Why is the car requiring so much less of a DC to achieve the same psi levels now? Thanks for your help, I know this was a long post.

sohcd16y8 · Post by **sohcd16y8** » Mon Mar 09, 2009 7:44 pm

Here is the map, since the max attachments is 3.

b20beast · Post by **b20beast** » Mon Mar 09, 2009 8:46 pm

i may be wrong but why are lines crossing in the fuel hi cam

sohcd16y8 · Post by **sohcd16y8** » Mon Mar 09, 2009 8:48 pm

b20beast wrote:i may be wrong but why are lines crossing in the fuel hi cam

Im not sure what your asking?

b20beast · Post by **b20beast** » Mon Mar 09, 2009 9:11 pm

in the 2d map

sohcd16y8 · Post by **sohcd16y8** » Mon Mar 09, 2009 9:18 pm

Probably because they are cells that dont get touched, ill have to look at it when Im home. What does that have to do with the boost solenoid?

Post by **Bugermass** » Tue Mar 10, 2009 1:34 am

I had some random overboosting issues with closed loop a while back but I never had time to track the issue down.. Kinda the same deal, it was working fine then all of a sudden it started acting all crazy so I just disabled it and went back to basic EBC.. I havn't played with it in a while, but there is some kinda bug, not sure what..

sohcd16y8 · Post by **sohcd16y8** » Tue Mar 10, 2009 7:38 am

Hmmm, was it similar to this in that all of a sudden it took a lot less duty cycle to run the same boost levels? Like in my case where 28% was 20psi dead on in the past and now 20% is 21-22 psi?

Post by **calvin** » Wed Mar 11, 2009 11:43 am

werd.. try without solenoid i don't have time to review now. but once i have time i'll review the files

sohcd16y8 · Post by **sohcd16y8** » Wed Mar 11, 2009 6:12 pm

I went ahead and ordered another solenoid to try. The wastegate acts fine by itself. The ecu is still working, and I cant see how the hardware would just not work (also confirmed by bugermass). I have a feeling that the solenoid itself might be sticking.

Maddog20 · Post by **Maddog20** » Wed Mar 11, 2009 9:53 pm

are you using a GM solenoid?? I have used the closed loop boost control option since the feature was introduced and never had an issue. But..I have had to alter the duty cycle a few times to reach the target due to using a GM solenoid. Do you have the solenoid mounted close to the manifold/downpipe?

sohcd16y8 · Post by **sohcd16y8** » Wed Mar 11, 2009 10:44 pm

I am using a Mac solenoid from Xenocron. The solenoid is not close to the manifold. I have a feeling the solenoid may be the issue, the change in DC was just wayyyyyyy to drastic too fast. I will know Friday if that is my issue or not.

sohcd16y8 · Post by **sohcd16y8** » Fri Mar 13, 2009 11:18 pm

Figured out my problem today, the small filter on the solenoid was dirty and clogged up enough to the point where the pressure in line to the top of the wastegate could not bleed off between cycles, which pretty much explains everything. New sintered filter and problem solved. Thanks for the help.

TopMountGSR · Post by **TopMountGSR** » Fri Mar 27, 2009 5:02 am

Is it necessary to run a filter on the middle port? We have never used anything on the middle port, just left it with nothing in it.