SOLVED-Erratic VR Sensor signal when cold

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FBD
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SOLVED-Erratic VR Sensor signal when cold

Post by FBD »

This was my first MS2 install, MS2 Extra Release 3.3.3, Ford EDIS module running a toothed wheel crank pulley, Coil pack, wasted spark, a path well trodden by BMW 2002 ers. Everything works great apart from initial start up when cold. The RPM gauge in TS goes nuts when I rev the car, redlines, fuel cut out triggers and obviously runs like crap. VR sensor has shielded wire, as does the IAT and wtr temp sensors (thought this might be the problem based on other issues i have read) but alas still having the issue. As soon as the car warms up, runs great? I keep thinking idle stepper noise? but the issue doesn't seem consistent with the stepper going through it's warm up? The steeper is the 4 wire Jeep idle valve. I've attached MSQ and a cold start datalog. Any assistance/suggestions gratefully received!
Attachments
2017-10-01_09.12.00.msl
Cold start
(28.55 KiB) Downloaded 23 times
2017-10-01_09.27.57.msq
Current Config
(117.1 KiB) Downloaded 26 times
Last edited by FBD on Mon Nov 13, 2017 3:43 am, edited 1 time in total.
prof315
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Re: Erratic VR Sensor signal when cold

Post by prof315 »

You have MASSIVE sync loss. And you don't have a VR signal going to MS if you are using EDIS but rather a square wave PIP signal. Are you using the VR input or the hall/ opto for a crank signal input?
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rickb794
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Re: Erratic VR Sensor signal when cold

Post by rickb794 »

Stale firmware....

No low resistance plug wires.

Must use resistor spark plugs.
Correctly identify your MS ecu here
Read the Do's and Don'ts to avoid the common pitfalls before starting your install or asking for help
Use only these manuals other manuals may cause brain damage or worse.
FBD
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Re: Erratic VR Sensor signal when cold

Post by FBD »

prof315 wrote:You have MASSIVE sync loss. And you don't have a VR signal going to MS if you are using EDIS but rather a square wave PIP signal. Are you using the VR input or the hall/ opto for a crank signal input?
Thanks for the response. Here's the EDIS module wiring. It all works fine apart from initial start up when cold when I'm getting that massive sync loss.
Attachments
edis4ew.gif
edis4ew.gif (9.68 KiB) Viewed 720 times
FBD
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Re: Erratic VR Sensor signal when cold

Post by FBD »

rickb794 wrote:Stale firmware....

No low resistance plug wires.

Must use resistor spark plugs.
Thanks for the response. Yep, using both, as for firmware wouldn't I have other issues not just initial cold start up? The car runs fine as soon as the RPM input stops bouncing all over the place, which is normally several minutes after start up?
rickb794
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Re: Erratic VR Sensor signal when cold

Post by rickb794 »

I missed the part about it being a temp related issue.

That would point at the sensor and wiring most likely.

Not so likely a software or internal problem.
Correctly identify your MS ecu here
Read the Do's and Don'ts to avoid the common pitfalls before starting your install or asking for help
Use only these manuals other manuals may cause brain damage or worse.
Marek
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Re: Erratic VR Sensor signal when cold

Post by Marek »

You may find that tweaking one the potentiometers just a tiny bit will resolve this.

I had a similar problem with my MS3/MS3X in that the MS3 crank inpout always worked fine at any temperature, but my cam inoput on the MS3X card only registered correctly above 5-10'c. Slightly adjusting the cam input potentiometer by a fraction when cold resolved the issue and it sync'd up and performed equally well at all temperatures thereafter.

Looking at the schematics, there was only one small component change (a resistor) between them, but I guerss the SMT components perform slightly differently to the conventional big (individually leaded) parts.

It may be that you have the same problem. One way to check that may be to warm the board/box (or maybe sensor) with a hair drier before your first start in the morning and datalog it to see whether the el;ectronics perform differently at startup.

kind regards
Marek
FBD
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Re: Erratic VR Sensor signal when cold

Post by FBD »

Interesting Marek,

I'll give that a shot and report back, thanks.
prof315
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Re: Erratic VR Sensor signal when cold

Post by prof315 »

Marek wrote:You may find that tweaking one the potentiometers just a tiny bit will resolve this.
kind regards
Marek
But only if you are using the VR conditioners for your PIP signal input.
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prof315
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Re: Erratic VR Sensor signal when cold

Post by prof315 »

FBD wrote:
prof315 wrote:You have MASSIVE sync loss. And you don't have a VR signal going to MS if you are using EDIS but rather a square wave PIP signal. Are you using the VR input or the hall/ opto for a crank signal input?
Thanks for the response. Here's the EDIS module wiring. It all works fine apart from initial start up when cold when I'm getting that massive sync loss.
I know the wiring diagram for EDIS well. You're missing the point here. Your EDIS module takes the VR signal from the CKP and outputs it to MS as a SQUARE WAVE signal (PIP). Open up you ECU and post a picture of the front side of the mainboard so we can see if you are using the VR conditioner in the board or the Hall/Opto conditioner. Which conditioner you are using will help us to properly help you.
Linfert Performance/321 Motorsports
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SCCA 2023 FP National Champion Tuner/electrical engineer
100s of MS systems built installed and tuned
Support the developers!
FBD
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Re: Erratic VR Sensor signal when cold

Post by FBD »

prof315 wrote:
FBD wrote:
prof315 wrote:You have MASSIVE sync loss. And you don't have a VR signal going to MS if you are using EDIS but rather a square wave PIP signal. Are you using the VR input or the hall/ opto for a crank signal input?
Thanks for the response. Here's the EDIS module wiring. It all works fine apart from initial start up when cold when I'm getting that massive sync loss.
I know the wiring diagram for EDIS well. You're missing the point here. Your EDIS module takes the VR signal from the CKP and outputs it to MS as a SQUARE WAVE signal (PIP). Open up you ECU and post a picture of the front side of the mainboard so we can see if you are using the VR conditioner in the board or the Hall/Opto conditioner. Which conditioner you are using will help us to properly help you.
Thanks prof315, yes did miss the point. I'm using the VR conditioner on the board and set it up as per the msextra docs (p60) if it will still help I'll post a pic as requested?
prof315
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Re: Erratic VR Sensor signal when cold

Post by prof315 »

Ok, as Marek mentioned, some tweaking to R56 ( and maybe r52 but I doubt it) may possibly get you straightened out.

The best way to deal with this issue would be to put a scope on the PIP signal when things are acting up. If the PIP signal is clean, it's a problem with the MS. If the PIP signal is NOT clean, the issue lies in the EDIS components, ( CKP, wiring or EDIS module) my bet would be on the module
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Support the developers!
DaveEFI
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Re: Erratic VR Sensor signal when cold

Post by DaveEFI »

If it helps, my VR input is set with R56 6 turns clockwise for EDIS8 PIP. R52 left fully CCW. On a V3 board - V3.57 may be different.

I looked at VR out with a scope, and set R56 for the best signal.
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FBD
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Re: Erratic VR Sensor signal when cold

Post by FBD »

prof315 wrote:Ok, as Marek mentioned, some tweaking to R56 ( and maybe r52 but I doubt it) may possibly get you straightened out.

The best way to deal with this issue would be to put a scope on the PIP signal when things are acting up. If the PIP signal is clean, it's a problem with the MS. If the PIP signal is NOT clean, the issue lies in the EDIS components, ( CKP, wiring or EDIS module) my bet would be on the module
I shall give that a go at the weekend and post back, many thanks I really appreciate your input.
FBD
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Joined: Thu Oct 13, 2016 4:14 pm

Re: Erratic VR Sensor signal when cold

Post by FBD »

DaveEFI wrote:If it helps, my VR input is set with R56 6 turns clockwise for EDIS8 PIP. R52 left fully CCW. On a V3 board - V3.57 may be different.

I looked at VR out with a scope, and set R56 for the best signal.
Thanks Dave, got it I should be able to get hold of a scope and give this ago, appreciate the input.
FBD
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Re: SOLVED-Erratic VR Sensor signal when cold

Post by FBD »

I tweaked R56 as suggested by pro315 and DaveEFI and that did the trick, the RPM signal is now steady when warming up as as yet no other issues!

Thanks for all the assistance, much appreciated as always.
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