sbf sequential e85 turbo sync loss cranking, mostly Solved !

[ttxpc]

Hi guys
A quick rundown on my combo, ms3x latest firmware, tunerstudio latest updates (both at time of writing),sequential fuel (e85/flex) running 36-1 diyautotune wheel and sensor for crank trigger and single tooth msd v/r distributor for the cam sync. engine is 363 sbf v8 healthy hyd roller ls1 t/body super vic efi twin garrett turbo's. fuel pump is magnafuel protuner 750

the problem :=
during cranking only and not all the time will not sync, shows no input from the crank sensor at all at times, sync loss reason 2, the instant it lights off, signal is clean and no problems, runs great making plenty of go.
is better if I unplug the cooling fans, which are oem AU Ford falcon twin fans in shroud, unsure if its also related to the wideband warmup, I find it strange there is no tooth log at all when its at its worst.
If I turn the igniton on and wait 10-20 seconds, then crank, most of the time it is much better, this allows the fans to cycle and the elec water pump to cycle also, and w/b will be warmed up and online

I have included the msq and a data log and a tooth logger file, I am a little unsure what to try next, I have a new set of plug leads to put on, I have tried 2 starters, battery is brand new 680cca, new leads 50mm cabling, battery is in the trunk, cabling to the crank and cam sensor is shielded and as far away from the ignition leads as possible, I think maybe a combination of noise from all the electric motors?
any help would be greatly appreciated

ps is only roughed in to approx 160kpa so far

[DaveEFI]

Your RPM graph in MLV looks rather spiky to me. Can't see the engine changing RPM that quickly. Not does the MAP follow it - as it would if the true RPM was changing. Of course it can run ok like that - but might give a clue as to why MS loses the VR signal when cranking.

Is your VR sensor wired all the way back to MS in one go - and using a decent twin screened cable? Connector to the VR sensor good too? Cable as clear as possible from plug leads?

If that is all good, I'd check the tips in the manual on adjusting the pots in the VR input.

[ttxpc]

Thanks Dave
I have set the hysteresis on the mainboard to 2.5v at the top of r54, haven't tried the sensitivity yet, will go there next
The main input is halleffect diyautotune sensor, shielded cable, vr is the single tooth cam input

[DaveEFI]

Ah. If hall effect, might be worth trying backing off R56 a little. (One turn anti-clock, then try) If you can't look at things with a scope.

[racerron]

Im not sure but just like the crank sensor I believe the cam sensor has to be hall effect also unless you have a VR conditioner. I have a 351 Windsor that I actually made my own cam sensor from a 302 distributor or cam sensor body out of an explorer all I did was install the 351 Windsor distributor shaft into the 302 body and welded the Half Moon shutter wheel to the top of the 351 Windsor distributor shaft

[racerron]

https://www.google.com/search?client=ms ... ECX6j1M%3A
This is a picture of a 302 cam sensor that you can switch out to make it a hall effect

[racerron]

here's a picture of my modified cam sensor for my 351 Windsor

[ttxpc]

I have a few of those lying around racerron, but I still run the msd as a distributor as well, Ms triggers a msd box, previously the pots were set fully ccw, then plus 6 turns as per the manual which left r54 at around 1.7v, no difference there

[racerron]

Okay sorry I didn't know you were running a MSD ignitions. I believe you have to do a VR conditioner Warrior cam sensor or in your case it would be the distributor

[ttxpc]

Thanks anyway racerron, didn't mean to come across as rude.
I'm running v/r cam into the ms3x conditioner

[ttxpc]

Found some ptfe coated shielded sensor wire, will redo both the crank and cam sensors, see what happens

[ttxpc]

replaced pug leads with no noticeable change, onto the sensor wiring

[Rick Finsta]

Based on the OP I wasn't sure what you were driving at with WB sensor warmup time, but the wideband is ignored for a set time period after starting - in your tune it is 30 seconds so it is certainly not affecting your sync loss issues (unless you think the heating cycle is causing noise? Seems unlikely).

[ttxpc]

Not sure Rick, I think it's starter noise at this point combined with everything else going on under cranking conditions. Is hard to nail down fir sure, turned wb off and it seemed better, then no different

[ttxpc]

So if, when cranking, I see no or sporadic teeth on the tooth logger, is it not enough signal from the sensors, or noise, even though the noise is not shown on the logger?
If you look at the tooth log I above, there is a long period when cranking where nothing shows at all

[ttxpc]

Redid the sensor wiring to both the cam and crank sensors, used ptfe shielded 3 core that was used in a helicopter install...
earthed both the earth and drain of the hall effect crank sensor to the ms3 main connector earth, and the earth/drain of the cam vr to the ms3 main connector earth. with the relevant sensor out's to their respective pins, Interesting now I had to remove the jp7 jumper on the ms3x to clear cam fault, whereas before I had to run the jumper to not get a cam fault.
Happy camper
Thanks guys

[Rick Finsta]

Great!

[ttxpc]

Problem not completely solved, some issues last night but not as severe

[Rick Finsta]

You don't have an oscilloscope, do you?

[ttxpc]

I do, I've got it to the point i can live with it for now, likely go to a hall effect in the distributor