How PW1 and PW2 could be different?

Tuning concepts, methods, tips etc.

Moderators: jsmcortina, muythaibxr

martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

How PW1 and PW2 could be different?

Post by martroy »

Hi,

When I was at WOT with my car, it looks like it missed but very fast. When I was looking datalog, it appears PW1 went to 0 but I didnt hit rev limiter or Something like that. What could make this happens and why when reviewing a datalog, PW1 and PW2 could be different that much? I'm not using EGO correction.


Thanks
turbo conversion
Super MS/Extra'er
Posts: 1281
Joined: Thu Aug 19, 2010 6:22 pm
Location: White House, TN USA

Re: How PW1 and PW2 could be different?

Post by turbo conversion »

:msq:

David
1976 Datsun 280Z L28ET Garrett GT35R T3-T04E stage3 50 trim 63 A/R housing custom grind cam 2000-6000 rpm 440cc injectors intercooled 18 lbs. boost
3" exhaust turbo back LC-1 o2 sensor Hallman manual boost controller EDIS 6 ignition batch fire 60mm throttle body 5 spd T5 borg warner 3.54 lsd
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

Cant join a datalog, its big like 13mo.


Thanks.
kjones6039
Super MS/Extra'er
Posts: 1986
Joined: Sat Jul 22, 2006 8:02 pm
Location: Eureka, NV USA
Contact:

Re: How PW1 and PW2 could be different?

Post by kjones6039 »

martroy wrote:Cant join a datalog, its big like 13mo.
Try trimming it.

Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/extra 3.4.2 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
TinyIOX from JBPerformance
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

I've found how to trim it.

Here's the log. thanks guys for helping me out.
Last edited by martroy on Tue Sep 19, 2017 7:12 pm, edited 1 time in total.
billr
Super MS/Extra'er
Posts: 6828
Joined: Sun May 15, 2011 11:41 am
Location: Walnut Creek, Calif. USA

Re: How PW1 and PW2 could be different?

Post by billr »

OK, now post the MSQ...
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

Here we go.
billr
Super MS/Extra'er
Posts: 6828
Joined: Sun May 15, 2011 11:41 am
Location: Walnut Creek, Calif. USA

Re: How PW1 and PW2 could be different?

Post by billr »

Is this, perhaps, related to the problem reported here?

http://www.msextra.com/forums/viewtopic ... 31&t=66098
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

billr wrote:Is this, perhaps, related to the problem reported here?

http://www.msextra.com/forums/viewtopic ... 31&t=66098
Hi billr, thanks for the fast answer and information you gave me. I dont think its related as I have a MS2 3,57 and the real concern is: How PW1 went to a pulse of 0 when not PW2 and no rev limiter active at that moment ??? In other datalogs, I've seen a good difference between PW1 and PW2 during a steady load witch should be close each other in a "2 squirts / alternating mode".
franksidebike
Experienced MS/Extra'er
Posts: 226
Joined: Fri Apr 08, 2005 2:08 pm
Location: Wathlingen, Germany

Re: How PW1 and PW2 could be different?

Post by franksidebike »

Hi
Your Differenz in PW1 vs PW2 are OK!
For safety: Open Different Bank Setting in Injector Dead Time and make the same Setting with Bank1!
Your PW1 to 0: Load the FW new and Test it.
Frank
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

franksidebike wrote:Hi
Your Differenz in PW1 vs PW2 are OK!
For safety: Open Different Bank Setting in Injector Dead Time and make the same Setting with Bank1!
Your PW1 to 0: Load the FW new and Test it.
Frank
Hi Frank, look at 368,095, you will see PW2 is lower than PW1, for me, its anormal.

I will do what you recommanded, and reload the firmware and give some test. I'll report back today.

Thanks
billr
Super MS/Extra'er
Posts: 6828
Joined: Sun May 15, 2011 11:41 am
Location: Walnut Creek, Calif. USA

Re: How PW1 and PW2 could be different?

Post by billr »

Want a guess? Try turning off the "launch control". That is the only thing I see that has some kind of threshold right at 4000 rpm. I'm thinking that if your input for flat-shift is flaky it could be triggering when not intended.
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

billr wrote:Want a guess? Try turning off the "launch control". That is the only thing I see that has some kind of threshold right at 4000 rpm. I'm thinking that if your input for flat-shift is flaky it could be triggering when not intended.
Lets say you're right. If thats the case, why I see a solid 1023 on ADC7, status1 to 9 and status2 and status3 to 0 while PW1 went to 0?
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

As requested, I did my homework and did what you guys asked.

Reloaded firmware
Put same deadtime for bank1 and bank2
I did change flat s*** limiter to 1500 RPM to see during normal road testing, if I will get the issue. I'm in the process of reviewing all logs but heres new MSQ and MSL with the issue happens on both banks !!!
billr
Super MS/Extra'er
Posts: 6828
Joined: Sun May 15, 2011 11:41 am
Location: Walnut Creek, Calif. USA

Re: How PW1 and PW2 could be different?

Post by billr »

Still just guessing, of course, but I would turn that "launch" completely off; make sure it is out of the picture.
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: How PW1 and PW2 could be different?

Post by jsmcortina »

With "Basic Trigger" it is possible that a noise pulse came in generating a false high RPM which tripped the rev limiter briefly. With the relatively slow speed of datalogs (compared to the engine) you won't always capture that.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

jsmcortina wrote:With "Basic Trigger" it is possible that a noise pulse came in generating a false high RPM which tripped the rev limiter briefly. With the relatively slow speed of datalogs (compared to the engine) you won't always capture that.

James
Hi James, what do suggest me to fix that issue? Tomorrow, I will disable launch/flat shift to test if it still there.
billr
Super MS/Extra'er
Posts: 6828
Joined: Sun May 15, 2011 11:41 am
Location: Walnut Creek, Calif. USA

Re: How PW1 and PW2 could be different?

Post by billr »

If that is the rev-limiter engaging, I wonder why we don't see the spark retarding along with the fuel cut?

Try turning off the rev-limiter, see if that eliminates the problem. (Just as a "diagnostic test", not permanent solution).

Is your "basic trigger" mechanical points, or some kind of electronic switch?
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

Ford TFI distributor.
martroy
Experienced MS/Extra'er
Posts: 306
Joined: Thu Jul 13, 2017 6:31 pm

Re: How PW1 and PW2 could be different?

Post by martroy »

As "stats" how many time I get the issue, on 8 WOT pull, I got the problem 2 times.

Today, I remove the fuel cut for revlimiter but keep spark cut and disable completely Launch/Flatshift option. I did 6 WOT pull and none gave me the issue. In the next days, will continue to run the car hard to try to make it happens. If the Launch/Flatshift was trigger, I dont understand with ADC7 remains to 1023 like if the input remains to the same voltage (5V) !!!
Post Reply