ocousins

Has anyone ever experienced the strange behaviour of huge ignition timing retard on throttle lift? I am running Apexi Power FC and anytime I lift the throttle to decellerate, the timing retards from (for example) 35 degrees down to 5 degrees, then returns to 35 degrees and gradually decreases normally with the RPM. If I hit the gas immediately following a throttle lift, the ignition timing remain really retarded for a few seconds before correcting itself. I get a really loud backfire pop when I lift. I have checked the ignition map and there is no cell with an ignition timing even close to what it is retarding to. I have seen it go as low as 0 degrees! Is this likely a hardware issue in the ECU? or perhaps some other ignition component? I have ruled out the CAS because I checked all the signal lines by back pinning the ECU with an oscilloscope, and they (all 4) are all crystal clear square wave entering the ECU. On a side note the ECU has other issues such as a really noisy reported RPM even though I am certain the CAS signal is perfect.

OK some more updates: I checked my cam gears, they were tight, as was the timing belt. When I thought about it, I realized it can't be a mechanical issue in timing because if there was (ie a loose adjustable cam gear) the engine would perform poorly, but the ECU wouldn't "know" the timing was off since its only reference is the cam. That is to say that if the cam phasing was out, the ECU wouldn't know it since it doesn't have a crank sensor. THat means my issue is either electrical or software. I found another peculiar behaviour. If I set my base timing, ie use a timing light to set idle timing to be what the PFC displays (20 degrees) then rev the engine after tightening the cam sensor, the timing light and the PFC commander go way off. THat is to say if both the timing light and the commander report a 20 advance at idle, when I rev the engine in neutral, the timing light reports 38 degrees, while the commander reports 28 degrees. Any thoughts or suggestions for more troubleshooting? Thanks

Well this is embarrasing, but apparently Hicas does have a fuse, found on in the inside box. The arc'ing battery terminal as I reattached battery must have fried it. A new fuse fixed the issue. I found it by checking each and every fuse as I couldnt determine the obvious fuse from the translated diagram

A couple of weeks ago my Hicas light of my R32 GTR came on. I checked the fluid, found it low and filled it. The light went out and I have had two problem free weeks. Today I pulled the coil cover off to inpect my spark plugs, spark harness ground, and ignitor ground. During this time I disconnected the neg battery terminal. When I was finished, I put it all back together, connected the battery and left the car idling for about 10 mins. When I got in it, I noticed the HIcas light on again, and the steering very heavy, almost as heavy as when the engine isn't even turning. I checked the fluid and its fine, did the air bleed procedure (full left and right turns with ignition off, then with engine running) and the light remains, as does the heavy steering. What could I have done by disconnecting the battery? Or how about disconnecting spark harness and ignitor? That's all that I touched and it's pooched now. Will try the Hicas diagnostic next, but not sure if the APEXI ECu affects that. Is there a fuse that may have blown by a arc'ing battery ground as I attached it? There was a pretty good spark because I had the trunk lid open when I connected it and the trunk light pulled a decent current Thanks!

Thoughts anyone? I will soon attach some images showing plots of my spark timing

Hey everyone, I have been living with a finicky and strangely behaving R32 for long enough and I thought I would probe your minds for some info on what my ignition issues might be. First a description of the symptoms: 1. Apexi commander RPM display is very "noisy', "spikey" or "unstable". By that I mean that at idle the RPM will average 950, but instantaneously vary as low as 850 rpm, and up to 1100 rpm. This happens way too fast to be a wandering idle, it is something electrical. I am certain it's not due to instantaneous rpm changes due to big cams and a lumpy idle because the same behaviour occurs over all RPM. Even when I am cruising at 3000 RPM the commander reports a RPM that varies quickly +/- 100 RPM without me feeling any surging at all. Note that the stock tach is stable 2. THe commander reports a spark timing that is also just as unstable or " noisy" this will very +/- 2 degrees all over the map, including idle even though I have disabled spark control of idle speed and made sure to make all ignition cells in the area of idle the same number just to prevent my noisy rpm from causing the ECU to interpolate between ignition timing cells 3 While cruising and watching the 10 second live plot of ignition timing, I noticed that if I ever lift the throttle, the spark timing retards about 10 to 15 degrees for a second or two then returns to a nominal value as I decelerate. This got to be so bad that as i accelerated and would shift, the first 2 seconds of accel in the next gear would be boggy as the ignition timing would retard 15 degrees when i lifted throttle before the change, and stay down after the shift for a bit. I changed the Cam angle sensor (with another used one) and this remains, although not so bad as to affect the next upshift My efforts to rectify: A.The first thing I did was check that the coils and ignitor are well grounded and they seem to be (although I haven't added a ground kit) B. I installed a different CAS. The spikey RPM remains, as does the unstable spark timing even at idle while ignition idle control is turned off. The short term ignition retard on throttle lift remains, but returns to nominal quicker C. I figured it was EMF interference from either the ignition coils or injectors so to test this I pulled the fuel pump fuse, and removed the CAS but kept it plugged in. I then spun the CAS with a cordless drill. I expected to see a noisy RPM and then alleviate in by disconnecting the coils, ignitor, or injectors one by one. But I was surprised to see a rock steady RPM reading despite hearing all the injectors and plugs firing. I am out of ideas of what to try next, the only variable I can think of that is left is the tolerance between the CAS and the Camshaft splines but I really hope to spare myself the cam change just for diagnostic purposes has anyone experienced something like my problems? does anyone have any thoughts of what to do next? I wouldn't care so much about this, but I am just about to purchase a Datalogit and I don't want erroneous rpm signals to cause an auto tune to be messing up with the wrong fuel cells

Hey everyone, I have been living with a finicky and strangely behaving R32 for long enough and I thought I would probe your minds for some info on what my ignition issues might be. First a description of the symptoms: 1. Apexi commander RPM display is very "noisy', "spikey" or "unstable". By that I mean that at idle the RPM will average 950, but instantaneously vary as low as 850 rpm, and up to 1100 rpm. This happens way too fast to be a wandering idle, it is something electrical. I am certain it's not due to instantaneous rpm changes due to big cams and a lumpy idle because the same behaviour occurs over all RPM. Even when I am cruising at 3000 RPM the commander reports a RPM that varies quickly +/- 100 RPM without me feeling any surging at all. Note that the stock tach is stable 2. THe commander reports a spark timing that is also just as unstable or " noisy" this will very +/- 2 degrees all over the map, including idle even though I have disabled spark control of idle speed and made sure to make all ignition cells in the area of idle the same number just to prevent my noisy rpm from causing the ECU to interpolate between ignition timing cells 3 While cruising and watching the 10 second live plot of ignition timing, I noticed that if I ever lift the throttle, the spark timing retards about 10 to 15 degrees for a second or two then returns to a nominal value as I decelerate. This got to be so bad that as i accelerated and would shift, the first 2 seconds of accel in the next gear would be boggy as the ignition timing would retard 15 degrees when i lifted throttle before the change, and stay down after the shift for a bit. I changed the Cam angle sensor (with another used one) and this remains, although not so bad as to affect the next upshift My efforts to rectify: A.The first thing I did was check that the coils and ignitor are well grounded and they seem to be (although I haven't added a ground kit) B. I installed a different CAS. The spikey RPM remains, as does the unstable spark timing even at idle while ignition idle control is turned off. The short term ignition retard on throttle lift remains, but returns to nominal quicker C. I figured it was EMF interference from either the ignition coils or injectors so to test this I pulled the fuel pump fuse, and removed the CAS but kept it plugged in. I then spun the CAS with a cordless drill. I expected to see a noisy RPM and then alleviate in by disconnecting the coils, ignitor, or injectors one by one. But I was surprised to see a rock steady RPM reading despite hearing all the injectors and plugs firing. I am out of ideas of what to try next, the only variable I can think of that is left is the tolerance between the CAS and the Camshaft splines but I really hope to spare myself the cam change just for diagnostic purposes has anyone experienced something like my problems? does anyone have any thoughts of what to do next? I wouldn't care so much about this, but I am just about to purchase a Datalogit and I don't want erroneous rpm signals to cause an auto tune to be messing up with the wrong fuel cells