EJ20K / SPEC C WIRING

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pavlo
Zen Performance
Posts: 406
Joined: Mon Aug 04, 2008 9:18 am

Re: EJ20K / SPEC C WIRING

Post by pavlo »

Your AVCS sensors are wired with reversed polarity, that is the issue.
secure
Posts: 242
Joined: Tue Apr 21, 2009 6:38 am

Re: EJ20K / SPEC C WIRING

Post by secure »

Okay, changing polarity easy. Does that mean AVCS solenoids are not working?
pavlo
Zen Performance
Posts: 406
Joined: Mon Aug 04, 2008 9:18 am

Re: EJ20K / SPEC C WIRING

Post by pavlo »

no it doesn't that's a seperate issue! But you should swap the polarity, then disable the VVT (raise enable rpm) then re-measure the vvtRaw values (add then to a log temporarily or just add gauges at 1-2hz so they spit out the values) and then redo you latch offsets.

If you're really keen you can set them when they are hot, this should dial out any changes caused by the increase in size of the engine when it's hot and the change in cam timing that it causes (about 3degree offset on the LH inlet cam).

The reason we do this, is if you look at the current waveform, the VR sensor means that we are reading position on a part of the wave that is quite shallow, and will not be as consistent as the very vertical line on the rising edge in your screenshot.

then check your solenoids are pulsing with output checking.

If you don't have the anti flyback diodes in the wiring to the solenoid they will not work with the 39% base duty (they will still click when pulsed though), raise that to 86% and they will spring into live, but beware it can have a negative effect on the reliability of the output driver on the ECU, and the PI control needs retuning a little for the much narrower duty window.

Once it's working, adjust the logging, I would go with the actual vvt angles, and maybe some error values at a lower rate which can quickly highlight a vvt failure.
secure
Posts: 242
Joined: Tue Apr 21, 2009 6:38 am

Re: EJ20K / SPEC C WIRING

Post by secure »

Thanks Paul, they turn back now =)

Image

Image

Now I came very close to MY05 avcs sensor settings; Base MY05 as follows 15, 194, 374,554


vvt2
16
195
375
555

vvt1
18
199
379
559

I have read Pat's write up about the Avcs and added 11 degrees of timings for some margin. I came up with the calibration file below.
pat wrote:By way of example, if there was a tooth at 19 degrees then we might choose the 30 degree latch point - if a belt can stretch 11 degrees there are more serious issues to deal with first! If there is another tooth at 199 degrees then we would also enable the latch point at 210 degrees. This needs to be done for every tooth on every cam that is fully retarded when no drive is supplied to the variator
Now the question is why the base MY05 STI map latch points 90,270,450,630 enabled ? I have enabled 30,210,390,570 deg. Am I wrong doing that?


Btw I have added shotkies in the wiring loom and can hear click sound. I will see if the new setting helps for spool
Attachments
2015-08-06 20-47-02 plus 0h08m59s S6#0167.SD
avcs logs
(562.27 KiB) Downloaded 538 times
SPECC9.SC
(307 KiB) Downloaded 539 times
pavlo
Zen Performance
Posts: 406
Joined: Mon Aug 04, 2008 9:18 am

Re: EJ20K / SPEC C WIRING

Post by pavlo »

I think you will be fine.

Essentialy the latch point is the angle at which the ECU will check for a VVT event.
The latch angle offset, is the angle the crank will have been at when that event was picked up with no cam advance.

From comparing the actual crank angle with the "normal" crank angle the ECU can calculate the cam advance.
secure
Posts: 242
Joined: Tue Apr 21, 2009 6:38 am

Re: EJ20K / SPEC C WIRING

Post by secure »

Image


When calibrating latch points/offset there was minor VVTInErr and readings remain sensible when the engine speed is increased.(cold engine)

Now checking the logs on a normal driving(hot engine) and I can see the VVTInerror 10 degree. VVtIn 40 degree. Is this normal?
johnfelstead
Posts: 26
Joined: Wed Jan 29, 2014 12:23 am

Re: EJ20K / SPEC C WIRING

Post by johnfelstead »

secure wrote: Fri Aug 07, 2015 1:18 am Now I came very close to MY05 avcs sensor settings; Base MY05 as follows 15, 194, 374,554

vvt2
16
195
375
555

vvt1
18
199
379
559

I have read Pat's write up about the Avcs and added 11 degrees of timings for some margin. I came up with the calibration file below.
pat wrote:By way of example, if there was a tooth at 19 degrees then we might choose the 30 degree latch point - if a belt can stretch 11 degrees there are more serious issues to deal with first! If there is another tooth at 199 degrees then we would also enable the latch point at 210 degrees. This needs to be done for every tooth on every cam that is fully retarded when no drive is supplied to the variator
Now the question is why the base MY05 STI map latch points 90,270,450,630 enabled ? I have enabled 30,210,390,570 deg. Am I wrong doing that?
The latch points need to have enough headroom to allow the cams to advance and still be in range.

You are using up to 40 degrees advance, so your latch point needs to be camraw +40 as a minimum, otherwise you are overshooting the readable range.

With a camraw value of 18, add 40 and that gives you 58, so you need to have a latch point of at least 60, to give a bit more headroom for if the cam over advances a little use 90. Same applies for the next latch point, you have 199 as cam raw, so 199+40= 239, that's too close to 240 for comfort so use 270 instead and so on.

Using your current setting of camraw 18 and latch point 30, as soon as you see more than 12 degrees advance you wont get a proper reading.

This is why the values of 90,270,450,630 were set in the base map.
stevieturbo
Posts: 1016
Joined: Sun Dec 07, 2008 2:04 pm

Re: EJ20K / SPEC C WIRING

Post by stevieturbo »

6 years later ?

weird.
secure
Posts: 242
Joined: Tue Apr 21, 2009 6:38 am

Re: EJ20K / SPEC C WIRING

Post by secure »

johnfelstead wrote: Tue Apr 06, 2021 7:12 pm

This is why the values of 90,270,450,630 were set in the base map.
Which base map? I have Syvecs MY05 base map and it is as follows;
LH 15, 194, 374,630
RH 17, 197, 378, 557

not 90,270,450,630
but I understood what you mean.


Btw, thanks for the late reply =)
I'm still on the same engine though! I am a fan of stock EJ207. What is weird was actually my old engine was spooling around 3400 RPM without AVCS. Same setup with a long spec c complete engine spools at 3200 rpm. Not a day and night difference.MY98 ports were quite big actually.
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