l made a big step today . I got the check Engine light hooked up and working. I found Haynes a bit confusing in what plugs to connect but I googled and found when I connected the Black"Read" connector and green one disconnected I got some codes up.
I Got
21 - Coolant Temp sensor
22 - knock sensor
24 - Air control valve
31 Throttle position sensor
Now I dont yet have a vss connected, interesting I didnt get the code for that- 33
l dont yet know if these are new or old codes, so I need to understand how to cancel and see if they Come up again
it may be possible with TPS signal missing that the conditions for determining VSS faults is dependent on those.
I know they are with other ECUs I played with.
here is an example for delco 808
"24- VSS. No speed sensor pulses when engine between 2000-4000 rpm,
throttle closed, high vacuum, not in neutral and all for 5
seconds"
The codes are stored in the RAM, they are cleared when the ECU is completely powered off for a number of sec.
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
VLAD
thanks for the feedback it helps me with my plan for tomorrow . I was hoping someone would comment tonight.
l didnt quite know if I have new or old codes. Is it as simple as disconnecting battery for l minute or more and I can be sure the codes are new and real?
Tomorrow l try to hook up the VSS kit to eliminate another possible trouble area
I bought the smallcar kit that attaches to drive shafts
in hindsight might have been easier to buy the RJES kit that just . attaches to the dash Speedo cable.
its should clear after a min or 2 without the battery. you can recheck the codes once there is power again but without starting the engine assuming its doesn't log codes until the engine is running. Usually there is a engine runtime delay before any error codes are logs and displayed (my experience nominal 30 sec).
this is just speculation based on other ECUs I have experience with and could be totally wrong for the suby ECUs but I can't imagine them being completely different to the OBD standards as thats what it is, a standard.
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
VLAD
Ok I will reset as you suggest , install the vss see if That changes keep
I guess if I can fix all the things causing the codes I might fix my high idle speed.
well code 24 shows your IAC has a fault, thats likely cause and TPS (24) fault will cause idle problems too.
you got a lot of error codes there 😀
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
There is a procedure to clear the faults but its long and complicated they will clear with no power but how long that takes depends on how good the ECUs internal battery is.
my first ecu only took 15 mins to clear as the battery was stuffed but my current one needs over 48 hours before it forgets stored codes.
vss code very rarely appears, only if it gets an abnormal signal, but the idle control valve fault is from not running a vss.
knock sensor is pretty normal, youll find the housing is probably full of cracks, mine sometimes throws the code if the sensor gets wet.
the green check connectors plugged in and ignition on is the ecu going through everything looking for faults, black plugs is just reading stored faults.
the coolant temp may have just been unplugged while you were mucking about with temp gauges, that will do it, they dont often go bad.
battery? really? these get stranger and stranger. have you seen the battery in them? or are you referring to the capacitors in them? coz caps can store charge for quite some time.
joel, you saying these can't tell if the vss is missing based on other info?
can't see how the IAC fault can be caused by missing vss, all other ECUs i work with fault the IAC if the steps or PWM in case of EEC4 bosch unit don't yield any idle speed or vacuum changes.
to really see if these are faults the the ecu sees currently, if may have to be connected up to a laptop with suitable software and read the ECU data real time if that is even possible with suby ECUs?
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
I've still got my original donor cars ECU in storage somewhere, I had to replace it as the A/C controls didnt work, I'll crack it open and see if there is a battery visible but could be capacitors like you say too.
It with the battery disconnected for under 15 mins wouldnt erase the codes but longer than that they were gone yet this new replacement one even after 2 full days still had them stored, it took 2 and half full days before they cleared.
I've never tried the manual clear process, it;s just too involved.
With the no VSS causing the IACV fault it really is pretty simple.
It happens during coasting.
If you have no speed input the ECU thinks the car is not moving and when coasting the TPS shows the throttle is shut so as far as the ECU is concerned the car is sitting idling but if you are doing say 60km/h and in 4th gear it will be spinning over at 2000rpm.
Thats when the ECU goes shit I cant get it back to 750rpm, IACV must be faulty.
You can even see it bring the check engine light on at those times.
I know a lot of people with early EJ engines that have run without speed sensors, it's pretty common most people just live with the little idiosyncracies it causes rather than pay for or make a VSS but they all get IACV fault but not one has ever got VSS fault.
No idea what it takes for the ECU to sense a VSS fault but just no signal at all doesnt do it.
seems a bit primitive with the coding if its can't determine if the VSS isn't there and chucks a IAC fault instead. 🙁 I wonder if suby ECU can even tell which gear its in?
comparatively speaking Delco/Delphi and bosch units from mid 80s can tell easily what is going in.
if it sees the rpm high, closed TPS, no speed and trys to lower idle it will see no effect on rpm. it looks at the MAP reading and determine its in an overrun state based on RPM vs MAP ( when in the
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
errr? half my post disappeared after it was posted?
I can't be bothered typing that out again😬
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
The early EJs just have nice simple management, thats what makes them good for conversions, they run an AFM not a map sensor right uptil the late 90s and the manuals just have a neutral position sensor.
They do have a clutch switch too but I think that was just for the starter safety interlock on overseas models and the cruise control.
Do the newer ones run MAF or MAP?
Most people including myself prefer MAP, its easier to tune and fastest response time and not limited unlike MAF which have a frequency range( for hot wire type ) and max metered air flow they can read.
Pretty popular at least in the general sense to do MAF-less conversions. ie. convert to MAP based systems.
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
hey Joel
I watched your Boosted VW videos , well done !
If I get the SA459 Subaru upper engine cleaner and spray it through the throttle body manifold will that also clean out the IAC
Trying to avoid taking the IAC out at this stage
what''s better sa459 or seafoam?
does it make a difference?
For intake system, I dissemble everything, paint all metal components and synthetic resin plastic parts in paint stripper and pressure wash.
Comes up brand spanking new! will little effort, even all the carbon goes normally in the first go.
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
Hi Paul.
I've only ever used the Subaru upper engine cleaner so can't comment on seafoam but the Americans rave about it.
Does anyone actually sell it in Oz?
Which video did you see? the one where i used the SA459 or the IACV service?
best way to clean up the IACV without removing it is shown in the IACV service vid by removing the hose to it and pumping some SA459 into the valve as well as the manifold.
You can go one step further and remove the electronic controller and manually open and close the valve to make sure its rotating smoothly and really get the cleaner moving around in there.
vlad01 wrote:Do the newer ones run MAF or MAP?
Most people including myself prefer MAP, its easier to tune and fastest response time and not limited unlike MAF which have a frequency range( for hot wire type ) and max metered air flow they can read.
Pretty popular at least in the general sense to do MAF-less conversions. ie. convert to MAP based systems.
they are MAP from about 98 onwards.
You wont get any arguments that MAP is better but the stock MAF on early setups works perfectly well and changing to MAP is pretty well impossible without swapping to aftermarket management or just late model stock management.
Hi Joel
I saw the one where you removed the IAC on the bench and all the black squid ink came out
I was wondering if i just spray the SA459 up top through the intake will it get down below and clean out the IAC? ( i am hoping this )
as the donk is already installed into the kombi engine bay it is a bit tight in there and hard to get to the IAC.
if u think spraying up top cleans everywhere I will try that thru the intake otherwise I just have to bang my head a bit , skiin my knuckles and try to get to that IAC
As for for the CEL codes I am still a little confused . I have read different views. If i remove power for a day does it clear the codes or do I actually have to go thru some procedure?, e.g. connecting black and green connectors , going for a drive etc.
Hi Paul,
I would spray the cleaner in from both the purge valve port on the throttle body and down the 19mm hose that leads from the plastic intake hose to the IACV.
You get best results with that stuff doing it on a warmed engine and let it sit for atleast 15mins.
You have nothing to lose trying it anyway.
Leaving your battery disconnected will erase all the stored error codes, but you will have to experiement to see how long it needs to be disconnected, as I was saying one of mine is only 15mins, the other in the car now takes almost 3 days.
This is the manual process for resetting but I've never tried, I just leave the battery disconnected.
This may not work without a functioning VSS though.
With engine at operating temperature, turn engine off. Place gear shift lever into park (auto transmission cars only).
· Locate the two ECU check connectors, for most cars they are located under the steering column and consist of a black plastic male and female connector, and a green male female connector. The exact location of the connectors varies with the different year models, but generally they are located under the steering column on the drivers side.
NOTE: sometimes they are still taped over with some small amount of plastic tape, so look hard, they will be there!
With the ignition OFF connect black to black and green to green.
· Turn on ignition, do not start the engine, (and for auto transmission, cycle the gearshift lever from park to neutral and back to park ), depress the accelerator pedal to full throttle and hold for a few seconds, and then release. Start engine and then drive for at least one minute, keeping road speed above 10 mph.
· ECU is now re-set.
· At this point the check engine light should start to flash the all clear signal (steady 1/2 second interval flashes). If the check engine light does not flash, or indicates some other sequence, there is a fault present in the system, and should be checked for necessary repairs.
· Once done, stop the car and turn off the engine.
· Disconnect the plugs.
Joel lhx for the advice
I am wondering if the reason is there is no consistent time it takes to erase codes is the fact it is a 20 year old ECU and I guess it might have some lithium or energiser bunny cell in it ?
Just like in the TV ad some can go longer than others?
I'm going to crack my old one open on the weekend and see if I can see a battery inside.
take a pic and post it up. be interested to see the guts
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
Sunnyjim wrote:Joel lhx for the advice
I am wondering if the reason is there is no consistent time it takes to erase codes is the fact it is a 20 year old ECU and I guess it might have some lithium or energiser bunny cell in it ?
Just like in the TV ad some can go longer than others?
CR type lithium batteries have 10 year shelf life, some non volatile RAM chips with integrated CR button cells have lasted over 20 years, seen one on youtube that still operating 27 years!
But this said, I never ever seen an ECU with a battery unless I have replaced the EPROM with NVRAM chip, which has a battery inside the chip.
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
Joel wrote:Hi Paul.
I've only ever used the Subaru upper engine cleaner so can't comment on seafoam but the Americans rave about it.
Does anyone actually sell it in Oz?
Which video did you see? the one where i used the SA459 or the IACV service?
best way to clean up the IACV without removing it is shown in the IACV service vid by removing the hose to it and pumping some SA459 into the valve as well as the manifold.
You can go one step further and remove the electronic controller and manually open and close the valve to make sure its rotating smoothly and really get the cleaner moving around in there.
vlad01 wrote:Do the newer ones run MAF or MAP?
Most people including myself prefer MAP, its easier to tune and fastest response time and not limited unlike MAF which have a frequency range( for hot wire type ) and max metered air flow they can read.
Pretty popular at least in the general sense to do MAF-less conversions. ie. convert to MAP based systems.
they are MAP from about 98 onwards.
You wont get any arguments that MAP is better but the stock MAF on early setups works perfectly well and changing to MAP is pretty well impossible without swapping to aftermarket management or just late model stock management.
challenge accepted!
😎 lol who wants a MAF-less drop in EFI system for EJ to VW conversion system?
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
Dug around
PCV really clogged at first thought someone has put a blanking plug as it was siezed shut. Worked it with a hole punch and some cleaner and got it working again
l dont. know if that is good enough or not . Perhaps I will still order a new one
as you remember my issue is I have a high Idle . at 950-1100 rpm . I notice after I fixed the PCV it is more like 850-950
I bit the bullet and went down to the IAC It was gunky but not as bad as in Joel's youtube videos. Cleaned it all out.
Then had a look at the coolant temp sensor as this is one of the 4 CEL Codes I have .
Using boiling water 212 F or 100C the resistance should be 176 ohms but mine was 220-360 Ohms. I did the test a few times.
So I dont know how accurate these things should be but according to Haynes and their temp chart the sensor is telling the ECU it is only 85C but it Is really 100C
So to be safe I should order a new coolant temp sensor
Brings me to the question what is the best E bay Site for quality subaru spares?
that would make your engine run richer than it should. i maybe throwing a code due to never "reaching" operating temp, well as the ECU sees it anyway.
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
vlad where do u order your subie parts from?
I will need ot pick up a coolant temp sensor and a pcv valve and cannot take the chance on quality
I don't, I use GM EFI stuff for just about everything but I do(readily available parts, very tunable), but have good experience with most EFI systems and had some experience wiring a suby EFI for an light plane some years ago, was pretty much like anything else except the odd connectors they use.
Im actually curious to know where you can buy suby EFI stuff myself, would love to make in my spare time a hybrid system running on a delco and mafless.
All the Japanese EFI stuff seems to be hard to find and obscure, only GM(delphi/delco) and Bosch are the well documented and readily available.
I get my gear from EFIconnection.com including even color coded wire because the quality is there unlike the EFI shops in Oz which I ended binning most of the stuff except one genuine Nissan connector.
👎
Good range of genuine connectors with eficonnection.
http://www.eficonnection.com/eficonnection/ConnectorSearch.aspx
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
I just get all my stuff through my local subi garage he'll get in any parts I need, let me know if you dont have any joy, but one thing I've learned is go genuine parts all the way.
They are not usually much dearer and work/fit right every time.
Anyway this better be worth voiding my 22 year extended warranty for....
Cracked it open and no battery in there.
must be capacitors, although 48+hours memory is pretty impressive on a 20 year old ECU.
The only part I can't really identify is this one marked X-tal
Any thoughts?
I dont really want to delve too much deeper, this all ECU still works fine except for the A/C controls which was the reason I had to replace it.
wow so much stuff and even a daughter board!
That thing is a quartz crystal, used for the clock generator for that processor next to it (the big chip) clock as in cyclic computation metronome like function, not clock as time you see on the wall
there is an empty socket there, which looks like an EPROM should be there. I wonder where the calibration and software is kept then?
Looks like there is no conformal coating either? hmmm.
Here is an ECU I am using atm for one of the projects with few mods. SXR board, allows higher speed serial data for logging and communication to the BCM, this ECU din't have those capabilities but now does. 😵💫
Also Dallas NVRAM which is a like an EPROM but can be written to at anytime through the ECU itself via the serial data. Which I just plug my laptop into the interface under the steering column.
There is a standard (coverless) memcal piggyback on the NVRAM board which allows use of the knock filter (white ceramic chip looking thing) and limp home mode network resistors.
Going to be setting one of these up for a mate but with USB port communications board in place of where I used the SXR so the ECU will directly connect to USB. Going to power a 5L EFI engine conversion on his SLR5000.
Joel, what does the Suby use for the crank trigger? its it a reluctor or haul effect sensor? I can't recall but seem to think it was reluctor?
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE
