Rb26 PRP 12 Tooth Trigger Issue

[Karljsw]

Hi Everyone,

Looking for some help with my issue of my crank trigger not working. I've done a search and have tried to follow what i've found but I still can't seem to get it to work. The ECU sees no RPM while cranking as well as No trigger 1, I have managed to get my Trigger 2 to work I think (It says its working/ seeing a signal while cranking at least).

I'm running a PRP 12 tooth crank trigger and a Yelsha D cam trigger. I'll attach a photo of the settings I've got and a trigger scope of what im seeing. Trigger 1 is seeing 1.47V and Trigger 2 is seeing 0.18V with the ignition on and engine off.

I've checked the wiring of the PRP trigger and its getting a 12v feed from a switched source, ground via the fury's ecu sensor grounds and 4.96V signal from the Trig 1 pin (Im not sure if this is correct). The gap between the sensor and the crank trigger wheel is the recommended 1mm from PRP

I've tried to wave a spanner infront of the crank sensor while cranking but it doesnt seem to work either. Have I just wired it up wrong or is the sensor a dud?

 

 

[Adamw]

The yelsa d cam trigger with 24-1 is not going to work as a sync.  You will need something with a single tooth, and preferably a hall sensor (reluctors with a single tooth on a small cam wheel typically will result in a slow sync due to low voltage when the crank is slow).  

And yes, there is no signal from trig 1.  It would be pretty unusual for a hall sensor to be DOA, so I would have a closer look at the wiring.  To confirm wiring to ecu is ok you can touch the signal wire to ground intermittently you should see the trig 1 signal in the ecu runtimes turn green and say yes. 

 

[Karljsw]

Hi Adam, 

Thanks for the quick reply. So I need something like the PRP cam trigger kit or the Franklin engineered kit with the single reference point?

Also figured out why the crank trigger wasnt working. The wiring to the ecu is all good the problem was the 12v feed was dropping to 3.4V while cranking. I jumped it straight to the battery and the trigger 1 was switching on when cranking. I just need to fix this at the fuse box and it should be fine.

If I were to get the PRP kit or the franklin engineered kit would I set it up as:

Trigger type 2 - optical/ hall

Trigger filter 2 - level 2

Trigger 2 pullup - On

Trig 2 edge - Falling

[Adamw]

Yeah one of those kits would work.  Or a factory CAS with one of the 24 & 1 discs in it (just using the 1 inner slot for sync). 

And yes those settings would most likely do it.  The trigger 2 edge may need to be rising or falling if one edge happens to clash with a trig 1 edge but you can check that with the scope once getting closer.

[Karljsw]

Hi Adam,

Thanks for the help. I've installed the new cam trigger and am now getting both trigger 1 and 2 turning green and saying yes in the runtime view while cranking and an rpm signal fluctuating between 150 and 250rpm.

I've taken another picture of the trigger scope but have no idea If it looks correct or not.

[Adamw]

Yep, looks fine.  Set edge to falling on both trig 1 & 2 if not already, then set base timing.

[Abed.Adham]

Hello Adam,

 

Could you please helping me wiring and setup Yeshla D trigger kit on my Rb25det neo.

I already fitted the kit but not sure how to configure it on Link XtremeX

[Vaughan]

This is the tune setup from my RB30det, your trigger offset may differ.

In terms of wiring you want to wire the sensor up to trigger 1 and signal ground, the triggerscope should look like the image below.

[Abed.Adham]

Thank you Vaughan, I believe trigger offset should be 98 for RB25 if I am not mistaken

[Adamw]

Don’t guess, you need to set it using a timing light.

[Abed.Adham]

Is there any tutorial videos how to do it? Honestly I didn't find anyone in KSA familiar with such things, they do basics only 

[Adamw]

Setting trigger offset is one of the most basic fundamentals of setting up an ecu, it must be done on every engine before tuning is attempted. Any tuner should know how to do this and would do it everyday.  Instructions below from the help file.  

 

 

[JOEL]

3 hours ago, Adamw said:

Setting trigger offset is one of the most basic fundamentals of setting up an ecu, it must be done on every engine before tuning is attempted. Any tuner should know how to do this and would do it everyday.  Instructions below from the help file.  

 

 

Hi Adam.

Are you able to recommend correct settings for 24 tooth AEM CAS Disc?
I've just installed one in my rb25 cas, correct settings (24 tooth, pull up on, falling)
Set base timing to exactly 15 Deg.
Get "yes" on trigger 1 and 2, but cant start up for some reason.

The scope also looks fine.

[Adamw]

Have you tried adding of subtracting 360 deg from your offset?  You are potentially sparking on exhaust stroke instead of compression stroke.  

[JOEL]

4 hours ago, Adamw said:

Have you tried adding of subtracting 360 deg from your offset?  You are potentially sparking on exhaust stroke instead of compression stroke.  

Perfect, thanks Adam, do you know why it would have to be -360 for it to run?

[Adamw]

It can be anything between -360 and +360.  Whatever makes it run with the correct timing is the correct offset.

[Karljsw]

Hi Guys,

 

I'm struggling to get this pig to run... It's 100% me but I have no idea what ive done wrong. Is it just a timing issue. (I've also emailed tech support but wanted to ask here if anyone was lurking over the weekend)

 

There is a log and my current base map attached. The only thing that I can see immediately jumping out is my battery voltage dropping to 9v during cranking.

 

Help I'm a complete novice

Datsun RB26 Log.llg Datsun RB26 29.1.22.pclr

[Vaughan]

I would recommend having Trigger 1 set to 24 teeth and cam rather than 12 and crank but that will make no difference. I suspect your issue is lack of fuel, you have it set to be a modelled fuel tune (so fuel table is volumetric efficiency) instead of a traditional fuel tune (where fuel table is a percentage of the master fuel value) but your fuel table numbers are much to low for a modelled tune. If you are set on using a modelled tune I would recommend doubling your entire fuel table as a starting point.

[Adamw]

I think some of the other posts in this thread have added confusion, someone above is talking about an AEM trigger, then someone else is talking about a YelshaD trigger etc.  So Vaughan's comment about the trigger isnt relevant to your PRP crank trigger.  

I notice in your log your fuel pressure drops to 100Kpa when cranking.  Fuel pressure cal doesnt look correct either.  And agree with Vaughan, your fuel table numbers are too small for modelled mode.  Battery voltage is very low and cranking RPM is consequently quite low, first start up will be easier if you can improve that.  Also if still no signs of life with those issues fixed then try adding 360 deg to your offset.