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4A-GE 16V Small Port - Trigger Signal Not Read


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Good day,

Engine is a 4A-GE 16V small port (converted to RWD config, and I also did all the ECU/engine harness years back). Was running fine before with the stock ECU with pretty much all the needed functions.

I have wired in the G4X MonsoonX, but now it seems that the triggers (using stock 24-teeth crank/G2 cam triggers) are sometimes being read, sometime not.
Surely it is not starting. Ignition is working as tested from coil output.
*Some of the ancillaries not yet connected (LC2 controller, AC clutch control, etc.) but all essentials are already connected.

What else am I missing as to why the triggers are not being read correctly? All connections are checked to be good from the ECU connector the loom side connector to dizzy.

Firmware 6.18.11

Trigger Scope.jpg

Trigger Scope1.jpg

Trigger Scope2.jpg

 

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2 hours ago, Adamw said:

In your first pic it shows a valid signal, but you have the 24T sensor connected to trig 2 and the signal tooth to trig 1, they need to be swapped.  

Wow, started after I swapped the pins on the dizzy connector!

 Thanks Adam. :)

Now time to complete the wirings, and also fiddle with the settings of the custom 2-wire IACV as it is going crazy shooting the idle very high. 

 

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There is a bug in the current firmware where the outputs for 3 wire idle valves sometimes dont get assigned properly.  I just checked your map and it is showing this problem.  If you look at the output pins folder at aux 1 & 2 they are both showing as "complimentary PWM", aux 1 shouldnt be complimentary.

To fix, go to your idle speed control settings, change the output to "none", then change it back to "Aux1/2", it should get assigned correctly 2nd time around.

r8HTncw.png

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@Adamw I'm using an aftermarket 2-wire ISC solenoid from NZEFI. I'm not sure what's the OEM for this one. I've set the PWM @120Hz as they recommended - though I'm having a feeling this ISC is just too big for my engine. :P looks like I have to make a restrictor so it does not draw too much air. 

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Sorry, I had somebody elses 4AGE map open which had the IAC set up problem.  Yours looks ok.

You should be able to completely close the idle valve so a restrictor shouldnt be needed. Does the idle slow down if you unplug the valve? 

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16 minutes ago, Adamw said:

Sorry, I had somebody elses 4AGE map open which had the IAC set up problem.  Yours looks ok.

You should be able to completely close the idle valve so a restrictor shouldnt be needed. Does the idle slow down if you unplug the valve? 

The mechanical idle valve has been blocked off (from before due to piston already stuck)...

If I fully close the idle air bypass valve screw, the ISC small opening seems to make it hunt for idle.

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42 minutes ago, Adamw said:

If it is hunting with the idle valve closed or at a fixed position then there is something else tune related going on.  Attach a log and your tune if you want me to take a look.

Thanks... 

It is hunting when I fully close the idle air bleed valve, then let the ISC solely control the idle. Sometimes it stalls. 

 I'll complete all the wirings, then I'll see if the idle hunting persists.

The way the exhaust smells, it seems like it is going lean. I'll be able to verify once my Spartan LC2 has been installed. :)

I'll keep you posted. :D

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I have for now disabled closed-loop idle control as I am still having issues with the ISCV.
The LC2 already connected. However on idle, it is having blips of like the engine would stall then restores rev back.

 

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It looks like youve got something coming through your ground circuit as there is a spike on both triggers at the same time.  Looks like the spark event form just one cylinder.  Is there anything different in one cylinder like  a non-resistor spark plug or something?  

Try bumping the arming threshold on trigger 2 at 1000RPM up top about 1.5 or 2V might help.

Also check your rotor phasing - to do this, turn the engine over by hand to about 15-20°BTDC, then pull the distributor cap off and make sure the rotor is nicely centered under one of the cap posts.  If not, rotate the distributor body until it does, lock it up, then set your trigger offset again to correct base timing.

puGArb4.png

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@Adamwhi... All plugs are similar resistor type. I'll check the inside of the dizzy later, maybe there's some debris by the tooth.

If it matters, the stock coil is actually only connected as a trigger to my old high energy capacitive discharge ignition box Mallory 6EZL. The stock igniter and ignition box are both grounded directly to cylinder head with a thick gauge wire (to minimize the ground loop). The ECU wire loom came through the right side of the car, then all ignition related wires came through the left side. 

I have adjusted the trigger 2 arming threshold @1000rpm to 2.5V, but still getting the spark scatter. 

Perhaps I'll find my spare dizzy assembly and try it out again with it. :)

Thanks...

 

 

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5 hours ago, essb00 said:

If it matters, the stock coil is actually only connected as a trigger to my old high energy capacitive discharge ignition box Mallory 6EZL.

I just looked that up on google, thats a weird idea, It must send the high voltage from the original coil straight back to the battery?  If you can it wouldnt be a bad idea to unplug that temporarily and run it on the stock coilk just as a test to see if the noise disappears from the triggerscope.  

 

5 hours ago, essb00 said:

Perhaps I'll find my spare dizzy assembly and try it out again with it.

I dont think that spike we see is coming from the trigger, it appears to be ignition noise getting into the system somewhere.  

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I have just connected the other dizzy assembly, the trigger signal seems cleaner. :)  the tiny signal on 360° seems to be the G1 which is not connected (gap already set to max). Would it make it any better if I connect both G1 & G2 trigger 2 and set the position as crank instead of cam? 

I had this Mallory Hyfire 6EZL for the past 11 yrs on the stock ECU and never had problems with it (except when the ground wire terminal corroded, where it also caused spark scatter). The reason I used this one with the 'EZ' trigger is that at least the stock ECU would not go crazy looking for the IGF signal as the stock coil is still present (not having to resort to using a tach adapter - which is more complex). I guess it is just sending the high voltage back to the same ground as the ignition box...

If ever I'll notice some spark scatter, I'll try to do your recommendation to just use the stock coil. :)

img20200929_143558.jpg

Trigger Scope4.jpg

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Update: I've been able to use the 2-wire IACV, though I still need to finetune the settings (PWM frequency/gain/min&max clamp, etc.) to make it respond properly to AC request. As of the moment I still have an idle up VSV opening with AC clutch engagement and the IACV is able to compensate plus or minus to maintain target idle speed. Though of course ideally the IACV should be able to handle it solely. 

I guess proper closed loop idle control is really tricky, huh? :P

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If you get rid of the dedicated AC VSV you can just adjust the AC Offset Table and the AC Idle up setting to change the IACV Position and the target idle speed respectively when AC is turned on, adjust these values so that the closed loop control doesn't have to respond to it because it has been taken care of by the open loop values.

Capture.PNG

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1 hour ago, Vaughan said:

If you get rid of the dedicated AC VSV you can just adjust the AC Offset Table and the AC Idle up setting to change the IACV Position and the target idle speed respectively when AC is turned on, adjust these values so that the closed loop control doesn't have to respond to it because it has been taken care of by the open loop values.

Capture.PNG

I adjusted the AC idle up and offset table, but the IACV is not responding fast enough with AC clutch engagement -the idle dips too much and eventually cuts-off (I've set AC control to cut-off at 750rpm and below. 

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2 hours ago, essb00 said:

I adjusted the AC idle up and offset table, but the IACV is not responding fast enough with AC clutch engagement -the idle dips too much and eventually cuts-off

Go to the AC clutch control menu and increase the clutch delay.  Also attach your map as it sounds like Idle ignition isnt set up well if it dips that much.

 

KY2MfAz.png

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I seem to have been able to make the ISCV work with the AC clutch now... Just a little bit more fine adjustments. Could you check if there's something I missed? If I put the Idle Actuator Max Clamp higher than 43%, that's when it hunts idle when AC is on. It seems to be stable and keeping target idle if I limit it at 43%.
...there's also higher tendency to hunt idle whenever I put the PWM frequency 400Hz or lower.

 

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