Intermittent boost control

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MM887
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Posts: 18
Joined: Mon Jan 09, 2017 12:44 pm

Intermittent boost control

Post by MM887 »

Ms1, 3.0, boost control issues

I'm having issues with the pwm to the solenoid being intermittent. Test light verifies the same, and I'm checking this at the center pin of the MOSFET, to rule out wiring harness issues

With key on and engine NOT running, solenoid may pulse for 30 seconds, 10 seconds, or even zero at times.

With the engine running, I get no pulse at all, except a momentary flash at WOT

Hardware or possible software issue.? I've heard of the boost control setup in an MS1 leaving a lot to be desired, but haven't seen anyone else with this particular issue

Hoping it's a setting issue, but I've been at it for longer than I'd like to admit today, just not seeing anything in my settings that stick out as an issue.. closed loop control turned off per the manual, open loop setting duty cycle dey anywhere from 10 to 90..TPS 10-99
Matt Cramer
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Re: Intermittent boost control

Post by Matt Cramer »

:msq:
Matt Cramer -1966 Dodge Dart slant six running on MS3X
MM887
MS/Extra Newbie
Posts: 18
Joined: Mon Jan 09, 2017 12:44 pm

Re: Intermittent boost control

Post by MM887 »

Here it is, Thanks!
Matt Cramer
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Re: Intermittent boost control

Post by Matt Cramer »

I'd like to see the data log of what's going on, too.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
MM887
MS/Extra Newbie
Posts: 18
Joined: Mon Jan 09, 2017 12:44 pm

Re: Intermittent boost control

Post by MM887 »

Heres a datalog of whats going on. It will pulse with power to the ecu, but stops immediately as soon as the engine is running...Sometimes with pulse again if I just kill ignition power to the engine

The green output 1/boost light at the bottom of tunerstudio is flashing when its pulsing, and nothing when engine is running or not pulsing. Leads me to believe its not a wiring or issue with the Mosfet
Matt Cramer
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Re: Intermittent boost control

Post by Matt Cramer »

The boost control doesn't engage when the MAP reading is below ambient pressure - that seems to be what's going on here.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
MM887
MS/Extra Newbie
Posts: 18
Joined: Mon Jan 09, 2017 12:44 pm

Re: Intermittent boost control

Post by MM887 »

I appreciate the info for sure, as that makes perfect sense. I didn't see that in the ms1 manual, so I assumed it was tps% only, didn't think being below the ambient KPA was an issue.

I will update in a few days for anyone who may have a similar issue in the future

Thanks!
mac1
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Re: Intermittent boost control

Post by mac1 »

Matt Cramer wrote:The boost control doesn't engage when the MAP reading is below ambient pressure - that seems to be what's going on here.
i've been here on the bench messing with my boost circuit not able to get a pulsed output from x4/js2. But I know the circuit works because I switched it to "Output 1" and set it on with TPS and got my Ground output from my TIP122.
What if I hook up a vacuum line to map and suck on it & power up the MS then the initial MAP will be lower, then back up to 95kpa & that should engage my boost control on the bench?
I'm able to drop the initial KP reading about 20 kpa by sucking on the hose

I am using
Js0 and Js1 for Water injection
js2 for boost
not using js3
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95 Probe v6-t MS1
00 Accent 2.0L-T,Ms1
14 Factory Five 818 MS2 4 ebc/meth only
03 Tiburon v6 SC 1st ever MS
93 Tracer KLDE,Compounds w/2 of everything, Twin Megasquirt ?
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Matt Cramer
Super MS/Extra'er
Posts: 17499
Joined: Thu Apr 16, 2009 8:08 pm

Re: Intermittent boost control

Post by Matt Cramer »

mac1 wrote:
Matt Cramer wrote:The boost control doesn't engage when the MAP reading is below ambient pressure - that seems to be what's going on here.
i've been here on the bench messing with my boost circuit not able to get a pulsed output from x4/js2. But I know the circuit works because I switched it to "Output 1" and set it on with TPS and got my Ground output from my TIP122.
What if I hook up a vacuum line to map and suck on it & power up the MS then the initial MAP will be lower, then back up to 95kpa & that should engage my boost control on the bench?
I'm able to drop the initial KP reading about 20 kpa by sucking on the hose

I am using
Js0 and Js1 for Water injection
js2 for boost
not using js3
Please also post the data log.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
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