PWM not sustaining boost

[slowerthanu]

I searched for quite a while through everyone else's PWM issues but they were miostly about getting the solenoid to work at all or about the inability to keep boost down. im having the opposite problem in one car in particular. and the other car i am having a range problem. they are both using version 1.4.8.

the first car is using a MAC solenoid. the hondata is in a P28 ECU. this car was working perfectly fine all last season and the beginning of this season. i had full control over boost with no issues. he put on some new tires and took it to the track for the first time this season, and i could not get the solenoid to make any changes at all. the strange thing is that it was not just going to max boost and it was not going to wastegate boost either. it would spike to 20psi and then fall off to 15 psi. it didnt matter what duty cycle i had in there, it would not change at all, so i had a 10.50 car doing 12.0's all day because i couldnt keep the boost from spiking in 1st and 2nd amd i couldnt keep the boost from falling off like crazy in 3rd and 4th lol. i just figured the solenoid was broken so i didnt save any of the logs from the track but i recorded a few on the street with different duty cycles and getting the same issue everytime. i will post those logs along with the tune when i get home to my laptop. What could be causing this? the solenoid is working. i set the activation pressure to negative so that it would be on while the car idled and it was definitely working. the wiring was correct to A11 as it had always been. the vac lines have not changed either and none of them seemed to be punctured or showing wear of any kind. this car is on a drag radial and therefore relies heavily on the ability to control power throughout the run so this is a pretty big failure right now :/

The second car is using the same version but it's using the old GM solenoid. i am seeing control with this solenoid but they are such small increments of boost for such huge changes in duty cycle. it seems like there is a huge range. To change the boost a single psi i have to use almost 10 percent. what could be causing this? I am used to the MAC solenoid having a sweet spot where the solenoid reacted very sensitively and anything below that sweet spot didnt make any changes. make changes from 10% all the way up to 80% but very small changes the whole way through. i will upload the settings for this car as well. i just figured i would post this up first to see if anyone else is having similar problems. Thanks guys!

[slowerthanu]

Here is the tune and two logs. all the testing i did was in 3rd gear so you will see in the tune that 3rd gear's pwm is the highest. The first datalog is with a higher overall duty cycle and it increases as rpms go up. the second log is a lower overall duty cycle and it decreases as rpms go up. the PWM setting in the current tune i attached has an even higher PWM. i didnt log the pull with the current settings but it did the same thing as the others in spite of the higher duty cycle. so no matter what i did with the PWM the boost still just spiked to 20ish then dropped hard. zero control.
i used to have a slight drop at higher rpms in that car but it was a 1 or 2 psi drop which is normal, and i was easily able to compensate for it and level it out with a slightly higher PWM duty cycle in the rpms where it was dropping off. this is different.

[slowerthanu]

any help would be great guys....

[Spunkster]

We need the matching datalogs and calibrations to be able to see what might possibly be happening.

[slowerthanu]

We need the matching datalogs and calibrations to be able to see what might possibly be happening.

ok well i will have to wait until tonight to get back to my laptop :/ the only difference in the tune was the 3rd gear duty cycles for the PWM. the PWM table was working correctly...in each datalog it was running the duty cycle it was supposed to be running based on the table. the boost just was not changing whether i had it at 65%, 75% or 85%. ill get those calibrations uploaded tonight but are there any corrections i am missing dealing with PWM that could be causing that big drop off that you sould see in the current one i uplaoded?