Microtech Rx72c probably need your help sir FD wont start
10-06-10, 11:48 PM
#27
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the OP has an FD REW engine with a fixed,, true crank CAS
the only adjust the OP has is in the mix trim
the OP must also realise that FD engines lack a true TDC or even -5 ATDC mark
they have a -20 ATDC mark,, for the trailing
the OEM ECU when being timed is using a 15 degree split timing at idle , so when timing is checked ON THE TRAILING T1 LEAD
then t1 = 20 ATDC,, so L1 must be 5 ATDC
to get around this you get out the protractor and remark the pulley for a TDC
else,, you also make all your low down trailing maps a 15 degree split,, and follow the OEM timing technique
to the OP-- is your ID screen telling you this is an FD configured ECU?
as while both timing systems are essentially 12/1 tooth technique
( 24/2 for the FC CAS )
i believe its possible the inbuilt offset in the ECU may well be different and may be insurmountable
( whilst any other brand of ECU will have aced it being user definable )
at any rate,,remark the pulley OR try timing the engine after ensuring the timing maps have a 15 degree split at low rpms
then lock the timing and use the t1 lead to align the timing mark
PS,, trailing is only going to fire once the engine has actually started
( which is why i suggested the remark of the pulley with a TDC or -5 mark to aid in setup with only the engine cranking and the pump disconnected )
the only adjust the OP has is in the mix trim
the OP must also realise that FD engines lack a true TDC or even -5 ATDC mark
they have a -20 ATDC mark,, for the trailing
the OEM ECU when being timed is using a 15 degree split timing at idle , so when timing is checked ON THE TRAILING T1 LEAD
then t1 = 20 ATDC,, so L1 must be 5 ATDC
to get around this you get out the protractor and remark the pulley for a TDC
else,, you also make all your low down trailing maps a 15 degree split,, and follow the OEM timing technique
to the OP-- is your ID screen telling you this is an FD configured ECU?
as while both timing systems are essentially 12/1 tooth technique
( 24/2 for the FC CAS )
i believe its possible the inbuilt offset in the ECU may well be different and may be insurmountable
( whilst any other brand of ECU will have aced it being user definable )
at any rate,,remark the pulley OR try timing the engine after ensuring the timing maps have a 15 degree split at low rpms
then lock the timing and use the t1 lead to align the timing mark
PS,, trailing is only going to fire once the engine has actually started
( which is why i suggested the remark of the pulley with a TDC or -5 mark to aid in setup with only the engine cranking and the pump disconnected )
Havent played with a timing light yet, have to get a friend over with one.
On another note: Do the CA sensors work as an on/off switch or do they see a fluctuation of current? Mine have constant continuity and really dont fluctuate when activated...
Im in over my head but i cant trust these shops here.
10-07-10, 12:03 AM
#29
talking head
OK, ECU is FD,, so that is a good thing,,, now just be aware that mark is 20ATDC and the best way to sort that to time the motor conventionally is to remark the pulley
CA sensors?? -- the CAS outputs are reluctor wave forms,, the reluctors are passive and generate there own current as they spin
in older dizzys they are 12V offset ,, so measure 12v when the ignition is on,, not moving
but most aftermarket ECU's will hook up with zero offset
but for the FD CAS,, unsure what you would expect ,, but i would expect the answer is in the FSM and that they are still reluctor type,, not hall effect
and your only gauge on it will be resistance across the device,, and a continuity check on the wiring
-- as i doubt you have an oscilloscope !
any micro install have these three knowns before starting first time
-- the TPS MUST be calibrated
-- the timing MUST be locked out and doubled checked with a timing light ( with fuel pump disconnected )
-- the map sensor must go to a true engine vacuum source,, and not a ported source,, and not a purge port
be sure to check all of these before trying to crank and run the engine and you will get much further first go !
CA sensors?? -- the CAS outputs are reluctor wave forms,, the reluctors are passive and generate there own current as they spin
in older dizzys they are 12V offset ,, so measure 12v when the ignition is on,, not moving
but most aftermarket ECU's will hook up with zero offset
but for the FD CAS,, unsure what you would expect ,, but i would expect the answer is in the FSM and that they are still reluctor type,, not hall effect
and your only gauge on it will be resistance across the device,, and a continuity check on the wiring
-- as i doubt you have an oscilloscope !
any micro install have these three knowns before starting first time
-- the TPS MUST be calibrated
-- the timing MUST be locked out and doubled checked with a timing light ( with fuel pump disconnected )
-- the map sensor must go to a true engine vacuum source,, and not a ported source,, and not a purge port
be sure to check all of these before trying to crank and run the engine and you will get much further first go !
10-07-10, 12:14 AM
#30
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OK, ECU is FD,, so that is a good thing,,, now just be aware that mark is 20ATDC and the best way to sort that to time the motor conventionally is to remark the pulley
CA sensors?? -- the CAS outputs are reluctor wave forms,, the reluctors are passive and generate there own current as they spin
in older dizzys they are 12V offset ,, so measure 12v when the ignition is on,, not moving
but most aftermarket ECU's will hook up with zero offset
but for the FD CAS,, unsure what you would expect ,, but i would expect the answer is in the FSM and that they are still reluctor type,, not hall effect
and your only gauge on it will be resistance across the device,, and a continuity check on the wiring
-- as i doubt you have an oscilloscope !
any micro install have these three knowns before starting first time
-- the TPS MUST be calibrated
-- the timing MUST be locked out and doubled checked with a timing light ( with fuel pump disconnected )
-- the map sensor must go to a true engine vacuum source,, and not a ported source,, and not a purge port
be sure to check all of these before trying to crank and run the engine and you will get much further first go !
CA sensors?? -- the CAS outputs are reluctor wave forms,, the reluctors are passive and generate there own current as they spin
in older dizzys they are 12V offset ,, so measure 12v when the ignition is on,, not moving
but most aftermarket ECU's will hook up with zero offset
but for the FD CAS,, unsure what you would expect ,, but i would expect the answer is in the FSM and that they are still reluctor type,, not hall effect
and your only gauge on it will be resistance across the device,, and a continuity check on the wiring
-- as i doubt you have an oscilloscope !
any micro install have these three knowns before starting first time
-- the TPS MUST be calibrated
-- the timing MUST be locked out and doubled checked with a timing light ( with fuel pump disconnected )
-- the map sensor must go to a true engine vacuum source,, and not a ported source,, and not a purge port
be sure to check all of these before trying to crank and run the engine and you will get much further first go !
Timing has not been played with yet
The ECU map sensor is hooked up to one of the two nipples on the UIM on the primary runners.
Thanks.
10-07-10, 04:36 PM
#31
Ok so you have an fd. No adjustment on timing and your timing cant be wrong.
Change the t_rpm Idle from 00 to 25 degrees that will help it idle.
You need to get it to stay on and get it warm and get it to clean all the excess oil and fuel out of the engine, and the tune may need tweaking. Starting it and expecting it to idle perfectly and all the majic to happen on its own and straight away is an unrealistic expectation.
Also do a datalog when you have it on and show us the log so we can diagnose the problem.
Change the t_rpm Idle from 00 to 25 degrees that will help it idle.
You need to get it to stay on and get it warm and get it to clean all the excess oil and fuel out of the engine, and the tune may need tweaking. Starting it and expecting it to idle perfectly and all the majic to happen on its own and straight away is an unrealistic expectation.
Also do a datalog when you have it on and show us the log so we can diagnose the problem.
10-14-10, 07:17 PM
#32
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All of a sudden im getting the HOM and REF errors, so I rewired them...
I got it to start for ~1 min and it slowly shut down after that. i might try to tow start it this weekend. If that doesnt work, it'll sit for another 6 months until I feel like messing with it.
I got it to start for ~1 min and it slowly shut down after that. i might try to tow start it this weekend. If that doesnt work, it'll sit for another 6 months until I feel like messing with it.
10-21-10, 12:06 AM
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Ok, when I try to start it, it wont attempt to turnover until i press the gas pedal [slightly]
Is is screwing up on the idle map, and trying to start on the load one?
Is is screwing up on the idle map, and trying to start on the load one?
10-21-10, 12:48 AM
#36
talking head
- 1 raising the effective compression due to higher chamber filling during inlet stroke
- 2 leaning the mixture momentarily
the ECU is still under a cranking threshold rpm,, and is only looking at the crank map
so the load map does not come to play until the engine catches and rises past the threshold for crank ( about 300 rpm )
at that point ,, if the engines is throttle open
it will jump straight to the run map
and see the poor vacuum as a signal to drown the engine thinking it is at load
the trick with initial start up is to wind on the throttle screw,, and disconnect and BACv
( wind on enough to amount to a 1500- 2000 idle )
recalibrate the TPS to this new throttle position
start the car with crank or bumpstart
and it will be held at this fast idle position,, and run on the fuel and ignition data that is the look up table for idle
( and not the ones for load,, with corrections for a cold engine )
set statik timing to 10 and all idle timing plots to a 10 BTDC minimum
( most engines will put up with this,, heavily ported ones may like 5 degrees more )
and also,, i remark the pulley for a 10 BTDC mark
for FD,, crank the engine by hand clockwise
stop the crank pulley one tooth short of the -20 trailing mark ,, this tooth is -30 degrees
and so is 10 BTDC
remark the pulley here
( for FC use protractors to measure the leading to trailing mark gap,, and remark using this,, clockwise forward from the old leading mark )
and this will aid in setting up the timing to be all in real crank degrees ,, and not offset -5 like many micros ,, and so make the timing light real and relative
PS
if you play the timing trim or static timing be wary as to what the microtech is doing to the tmax and the timing map,, it has a nasty habit of shifting these around for you
Last edited by bumpstart; 10-21-10 at 12:54 AM. Reason: PS
10-30-10, 10:29 PM
#37
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Alright, me again. It started right up and then died 30 seconds later, could not control it with the pedal.
HOM and REF came up, and so did RPM.
So since i rewired the plugs, my next step is to rewire the entire length of the CAS wires. Any suggestions as to how/what to cover it with. ive seen a thread where microphone mesh was used, and the use of tin foil... i know it will be grounded to the ecu.
Just need some pointers.
HOM and REF came up, and so did RPM.
So since i rewired the plugs, my next step is to rewire the entire length of the CAS wires. Any suggestions as to how/what to cover it with. ive seen a thread where microphone mesh was used, and the use of tin foil... i know it will be grounded to the ecu.
Just need some pointers.
10-30-10, 10:51 PM
#38
talking head
go to an electronics store and buy 3-4M of shielded 4 core wire
( even the almost phone/microphone sized wire will do )
this already has the wire or foil shield and you take it the long way around the bay to avoid coils and wires and alternators
- also bring it through its own firewall hole
if it sees alt cables or HT wire you make the effort to cross them at right angles and not along them
the shield ties to earth as close to the ECU as possible
these are not normally necessary with a microtech
but are on some older other platforms with some brands of inductive pickups
i think there is other issues ,, if it was a dizzy CAS i would be recommending exchanges and regaps and polarity check at the wiring
with FD there shouldn't be all that much to check besides making sure your wiring polarity is fine
( even the almost phone/microphone sized wire will do )
this already has the wire or foil shield and you take it the long way around the bay to avoid coils and wires and alternators
- also bring it through its own firewall hole
if it sees alt cables or HT wire you make the effort to cross them at right angles and not along them
the shield ties to earth as close to the ECU as possible
these are not normally necessary with a microtech
but are on some older other platforms with some brands of inductive pickups
i think there is other issues ,, if it was a dizzy CAS i would be recommending exchanges and regaps and polarity check at the wiring
with FD there shouldn't be all that much to check besides making sure your wiring polarity is fine
11-02-10, 12:58 AM
#39
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OK new question:
Since microtechs website technical drawings show two different ways to wire the same CAS connections, which one is right?
http://www.microtechefi.com/pdf/LT10SubaruIgn.jpg
This one above shows the RED wire directly next to/under the BLUE/YELL ground wire and the GREEN diagonal from the ground. Its the only diagram for the LT10S... but for a boxer engine.
http://www.microtechefi.com/pdf/LTX8...ries6FDign.pdf
This one shows the RED wire from the crank signal DIAGONAL from the ground wire on the 4way plug... and the GREEN directly under the ground...
So which one do I follow?
My 4 way plug at the ECU has the RED wire Diagonal from the ground (BLUE/YELLOW) and the GREEN directly under the ground. The sheath is grounded an inch from the plug.
Since microtechs website technical drawings show two different ways to wire the same CAS connections, which one is right?
http://www.microtechefi.com/pdf/LT10SubaruIgn.jpg
This one above shows the RED wire directly next to/under the BLUE/YELL ground wire and the GREEN diagonal from the ground. Its the only diagram for the LT10S... but for a boxer engine.
http://www.microtechefi.com/pdf/LTX8...ries6FDign.pdf
This one shows the RED wire from the crank signal DIAGONAL from the ground wire on the 4way plug... and the GREEN directly under the ground...
So which one do I follow?
My 4 way plug at the ECU has the RED wire Diagonal from the ground (BLUE/YELLOW) and the GREEN directly under the ground. The sheath is grounded an inch from the plug.
11-13-10, 05:47 PM
#40
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Just for clarification, which sensor is CRANK INPUT 1, the 12x white plug/REF or the 1x grey plug/HOME?
Im having a problem getting the correct info...
Im having a problem getting the correct info...
11-16-10, 06:45 PM
#41
talking head
micro green = home tooth= single tooth FD, twin tooth FC ( crank input 1 )
the Vr ( - )'s tie together to the micro black wire ( in the ignition input bundle )
which should effectively tie them to earth
11-17-10, 11:18 AM
#42
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micro red= trigger tooth= 12 tooth FD , 24 tooth FC ( crank input 2 )
micro green = home tooth= single tooth FD, twin tooth FC ( crank input 1 )
the Vr ( - )'s tie together to the micro black wire ( in the ignition input bundle )
which should effectively tie them to earth
micro green = home tooth= single tooth FD, twin tooth FC ( crank input 1 )
the Vr ( - )'s tie together to the micro black wire ( in the ignition input bundle )
which should effectively tie them to earth
I couldnt get a straight answer from Microtech. Their website shows a Subaru wiring diagram for my ECU model LT10S, but then theres a diagram for an older ECU LTX8 for an FD3S. They dont match. So I email them and ask which one to use, they send me one ive never seen before which again is totally different than the other ones. So i ask why the wires are completely opposite on the diagram, and they tell me the original way (contradicting the one they sent me) Local shops in the area have had the same problem with the diagrams.
So I gave up trying to get help from them.
11-17-10, 08:03 PM
#43
talking head
Thanks! The car no longer throws codes.
I couldnt get a straight answer from Microtech. Their website shows a Subaru wiring diagram for my ECU model LT10S, but then theres a diagram for an older ECU LTX8 for an FD3S. They dont match. So I email them and ask which one to use, they send me one ive never seen before which again is totally different than the other ones. So i ask why the wires are completely opposite on the diagram, and they tell me the original way (contradicting the one they sent me) Local shops in the area have had the same problem with the diagrams.
So I gave up trying to get help from them.
I couldnt get a straight answer from Microtech. Their website shows a Subaru wiring diagram for my ECU model LT10S, but then theres a diagram for an older ECU LTX8 for an FD3S. They dont match. So I email them and ask which one to use, they send me one ive never seen before which again is totally different than the other ones. So i ask why the wires are completely opposite on the diagram, and they tell me the original way (contradicting the one they sent me) Local shops in the area have had the same problem with the diagrams.
So I gave up trying to get help from them.
--the LTX8 diagram is probably the most correct
good to hear you are fighting through it , does i run yet ?
11-17-10, 09:07 PM
#44
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No it still doesnt run, havent really tried that much.
i need to redo the main test of the injectors/ignition, and if that passes, realign the TPS...
i need to redo the main test of the injectors/ignition, and if that passes, realign the TPS...
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