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I also need to check my wiring. This could be as simple as a wire crossing my CAS wires and causing some EM interference or maybe a loose ground.
+1 before you buy anything you might just check the gap of the sensor to the wheel. like use a piece of paper or something and then spin the engine over and make sure its the same the whole way around.
and then yeah the wiring is a thing too. in fact while i have seen the OE sensors fail (once) the rest of the time its the wiring/connectors. on a stock car the wiring gets baked.
+1 before you buy anything you might just check the gap of the sensor to the wheel. like use a piece of paper or something and then spin the engine over and make sure its the same the whole way around.
and then yeah the wiring is a thing too. in fact while i have seen the OE sensors fail (once) the rest of the time its the wiring/connectors. on a stock car the wiring gets baked.
My wiring is a new harness from Chris @ LMS-EFI -- new as in like two years ago but I'm going to verify that no other wires cross over them. I'll see if I can get a fealer gauge and check the gap per the FSM.
Ray told me "Trigger only available with pulley assy. $258.31 - hub, trigger, and both pulleys". Add another $150ish for the CAS sensors. I def don't wanna dump $600 until I rule out other options.
I forget what ECU you're running (Haltech?) but if it has a "trigger scope" display/logging feature built in to the ECU/tuning software, you can use that to diagnose any potential issues with CAS wiring and its functionality. In the Link, it works pretty much like hooking up an oscilloscope to your CAS sensors - you get a nice log of output voltage vs. time for each CAS sensor, so you can clearly see if there are any timing errors and/or amplitude hiccups in the trace.
I am running a Haltech and Nelson did email me last night with a link to a video on how to use the Haltech to scope out my signals. My engine harness was made by Chris at LMS-EFI so I think it's pretty solid quality. I'm going verify routing to make sure it doesn't cross the alternator or spark wires at all.
I found a blog post on Haltech's website saying that the FFE Hall Kit is good for FC's but that the improvement over OEM setup on an FD is negligible. I'm going to try that and also measure the gap between the CAS and the wheel as well.
What's the price differential on "best solution available" to "generic possibly good enough maybe shitty"?
Given the $65k I've put into this car, it's not far off from selling it and moving on as my differential. The sunken cost fallacy is strong on this thing. $1000 yesterday to rent a dyno and tune and now another $300 ($600 if I want to replace the pulley). I keep thinking the bleeding will stop but it doesn't...
Ill Oscope the CAS and check the gap and wiring routing before I decide I need to spend $300 on something that may or may not be my issue.
BTW, one of the Rock Auto brands that make the sensor is NTK, which is owned by NGK. Another is Delphi, which is now owned by Borg Warner. They happen to be the two most expensive ones at about $75 each, which is still half the cost of a Mazda branded one. I def know there are some cheap *** brands on Rock Auto.
The OEM CAS setup is CRAZY reliable. It's just a magnet. Metal trigger wheel passes in front of it, it makes a pulse, there ya go. They don't short out, wear out, etc. It's as solid state as it gets.
The only issues I've ever seen are bent trigger wheels (possibly from a catastrophic belt failure or mis-handling when the engine was apart) or bad wiring. That's about it.
If you are getting a spotty every once in a blue moon error, I wouldn't worry about it. You're going to cause more problems. Leave it be. One dropped timing event at 7000 RPM isn't going to cost a motor.
The OEM CAS setup is CRAZY reliable. It's just a magnet. Metal trigger wheel passes in front of it, it makes a pulse, there ya go. They don't short out, wear out, etc. It's as solid state as it gets.
The only issues I've ever seen are bent trigger wheels (possibly from a catastrophic belt failure or mis-handling when the engine was apart) or bad wiring. That's about it.
If you are getting a spotty every once in a blue moon error, I wouldn't worry about it. You're going to cause more problems. Leave it be. One dropped timing event at 7000 RPM isn't going to cost a motor.
Dale
Yeh.. that's my thought too. Every event drops my engine in protection mode though. Just trying to avoid that for my track day next month. I will at least check the gap. That seems like an easy thing to do along with wiring but I trust that @C. Ludwig harness is solidly built to shield against EMI.
Run a scope trace. That will tell you what you need to know. May be a simple trigger threshold adjustment that needs to be made. The default values are usually pretty good but if the air gap is off a bit the values may need to be adjusted. A damaged tooth could also be an issue. What trigger are you running? Stock?
Run a scope trace. That will tell you what you need to know. May be a simple trigger threshold adjustment that needs to be made. The default values are usually pretty good but if the air gap is off a bit the values may need to be adjusted. A damaged tooth could also be an issue. What trigger are you running? Stock?
running OEM trigger setup. If I had a damaged tooth, would i see errors more consistently?
im out of the country for work but I’ll try to scope it next weekend when I’m back. Since I can’t replicate it, should I just run a scope and free rev the engine and capture what happens?
running OEM trigger setup. If I had a damaged tooth, would i see errors more consistently?
im out of the country for work but I’ll try to scope it next weekend when I’m back. Since I can’t replicate it, should I just run a scope and free rev the engine and capture what happens?
OE would be really hard to damage a tooth, I would think. Yeah, run the scope at a variety of rev ranges.
Here are the two images from my scope. I really didnt know what to set the scale to for each channel so I just adjusted it until I got a picture that looked "ok". One is at idle and one is during a free rev to about 6500rpm. I have no idea if these are good or bad...but I guess I would have expected the yellow line to be more squared off?
Those traces look pretty clean to me, not seeing any discontinuities in the timing sync or gross differences in amplitude. What do the 4 channels of data/traces correspond to though? My assumption is the yellow & orange (channels 1 & 3) correspond to the raw VR sensor output signals, yellow being the 12 tooth e-shaft position signal, and orange the 1 tooth per e-shaft rotation sync signal. The cyan & purple (channels 2 & 4) are probably those same signals after your Haltech ECU conditioned them for processing.
Those traces look pretty clean to me, not seeing any discontinuities in the timing sync or gross differences in amplitude. What do the 4 channels of data/traces correspond to though? My assumption is the yellow & orange (channels 1 & 3) correspond to the raw VR sensor output signals, yellow being the 12 tooth e-shaft position signal, and orange the 1 tooth per e-shaft rotation sync signal. The cyan & purple (channels 2 & 4) are probably those same signals after your Haltech ECU conditioned them for processing.
The channels are shown in the column on the right but your assumptions are correct.
Well it appears my trigger wheel is bent. Using a feeler gauge, I could see it was in spec for a few points I sampled but then I visually looked at it and turned the pulley and I can see where it def isn't straight. See this video:
I didn't have time to pull it off but I was told it could also just not be seated correctly so I need to double check that. If it is bent, my options are to find a good used one or probably move to the FFE VR or Hall effect kit. Ray Crowe told me the OEM Trigger Wheel only comes as part of a pulley set and it's over $300.
I have an extra sitting around I'm sure. Let me know if you want it and I'll find it.
Thanks! I got @aplscrambles checking since he's local to me but you're my next go to if he doesn't have one in good shape. Aside from having a "new" trigger, I haven't seen much compelling info for an FFE kit in terms of benefit over OEM.
I pulled the wheel off and placed it on a somewhat flat surface (the cover of my rolling tool chest) and sure enough, it's warped. I'm debating if I should just take a hammer to it and try to flatten it out, even though it won't be perfect and try it out or just find a solid used one / FFE kit?
05-24-23, 08:31 AM
