darom

Hi Weber, this forum is a little slow I just went through the microsquirt installation on my 76. Here is the thread showing the location for the MS (RH side) and the relay board (LH): I separated 12V relay board wires from the ECU's to avoid any interference. I also didn't want to put the MS board inside the engine bay. Regards, Den

I swapped the HALL sensor's 5 vrf with a 12v feed. This time all the sync losses are of my doing. For ex., adjusting the AE or WUE tables and exiting the windows, causes the ECU/engine stumble (almost like burning the changes), which generates "a reason 2" sync loss. It might be a psychological effect on me, but the car seems to idle smoother with a 12v feed to the HALL sensor. I managed to lower the idle by putting 14.x timing degrees. Thanks to everyone who helped with my issues! Should I enable the Closed Loop idle now? I don't mind keeping the Open Loop, I am just looking for any benefits of CL vs OL. 2024-11-23_15.22.20.mlg 2024-11-23-before-VE-smoothing-out.msq

The shield is grounded at the microsquirt's sensor ground location. I might try the 12v feed to the HALL sensor. I recorded two logs while doing a warm-up enrichment autotune tonight. The 1st one picked up only 2 sync losses, the 2nd - 11. I'd admit I was committing the burn to ECU commands which I noticed causing some of the sync losses. But not all 11 of them though. I also don't see any sync loss 'consequences' on my engine running. 2024-11-22_16.45.52.mlg 2024-11-22_16.53.40.mlg 2024-11-22-adjusted-ASE-taper.msq

Yes, thanks. I am using a 1k pull-up resistor with the HALL sensor wire. I followed the msextra's microsquirt doc on its wiring. I also haven't played around with signal filtering in TS.

Thanks, Steve! I will put 4-5 min steps instead. I noticed that every day (here in WI, we were at 45-50F for the past 3 days), my engine startup/warmup bevaves differently. I had to fiddle with the VE table/timing to get a stable idle. It might explain this if my IAC is not predictable and can't keep its position. I have been doing some reading and it seems that 5v vref switch to a 12v feed for the HALL sensor most of time doesn't resolve a sync issue. I have an osilloscope and would try logging the HALL sensor's output. Would you recommend switching over to the closed loop idle mode or stay with the open loop? I have no a/c, the radiator fan is not electric.

Yesterday I drove the car with the autotune running. I started a thread on msextra about my sync loss issues at: idle/IAC question if someone has time to review my tune/datalog. Thanks

Hi guys, What should be my idle fuel pressure? I have been running a FPR set at 43 psi without vacuum attached, which translates to 35-36 psi at idle (440cc fuel injectors). Is this an ok FP for operating these injectors? I finally got my idle sorted out with the Open Loop mode. The IAC is a sob, makes annoying noises, and I don't trust it that it stays in the set position 100 percent (I set mine in Always On). The idle would occasionally dip accompanied with the IAC noise. I'd try getting another unit to test. Thanks! 2024-11-12-good-idle.msq

Protunerz got back to me and suggested dremeling the edges off in the throttle body. First I tested it while pointing my air compressor's nozzle at it and it made the annoying noise. Removed the throttle body and took sharp edges of openings with a dremel tool: It passed the air compressor test. After installing it, the noise is gone 80 percent, there is still some noise when the throttle blade opens up.

I found out that the IAC plug in my throttle body is actually leaking air, possibly causing this RPM increase. I sent an email to Pro Tunerz asking if this is intentional or if their plug should be sealing the opening 100 percent.

yes, same problem it seems with these intakes. I used a thin layer of Permatex Ultra Copper, the leak is stopped, i checked with my smoke leak detector. I fixed my timing table (more conservative numbers), re-calculated my Bosch 0280155968 injectors flow at 36 psi (without vacuum it is at 43 psi), and re-generated my VE table using the built-in TS calculator. 43.5 PSI (3 BAR) 430 cc / min = 41 lb / h Calculation: old/original fuel pressure = 43.5 New Fuel Pressure = 36 Size of Fuel Injector in lb/hr = 41 New flow/Size of Fuel Injector = 37.298 lb/hr or 392.01 cc/min The IAC is disabled, the valve opening is plugged. I can't re-check the idle startup with engine cold at the moment, but when warmed-up, I can't get the RPMs lower than 1.5-2k. The only air leak is at the throttle body with the blade which is barely open (if I close it more, the car dies). The engine's vacuum is at 15-16 at the 1500 rpm. My valve cover vents the gases via a small filter. The PCV valve is connected and operational. If someone has time to review my tune with a datalog and tune for any issues, I'd appreciate it. Should I proceed with turning my IAC on at this point? Or I need to test the cold startup before going with the IAC enabled? Thanks. PS With the throttle blade barely open, the car is making a loud annoying whistling noise. With IAC installed, the blade will be completely closed and this nonsense should stop, I hope. CurrentTune.msq 2024-10-27-no-IAC-VE-inj-changed-calculated-flow-7.mlg

Replaced the MAP sensor, it is properly showing the kpas now. I have a bad air leak around cylinder 1, protunerz intake didn't seal the gasket. I did install it following the torque specs and order. While running, the air leak was audibly noticeable. I removed the intake, and didn't see any warpage. Ordered a new gasket. With GM IAC installed and in a closed position, the throttle body is making high pitched whistling noise. I guess the shape of the opening for the valve makes this bad harmonics issue. I also noticed my fuel pressure was around 50 psi. Adjusted the FPR, it is around 40-43 psi now.

Sounds good, thanks Steve. For now I will build a conservative timing table with max 36-38 degrees. I've been messing with my GM IAC I got from Protunerz. Managed to catapult the pintle into oblivion a few times. I didn't realize there is no stop. My max homing/closed/moving is at 160 steps. The IAC properly extends and stops at whatever CLT temperature is at. If I set the IAC at always on/hold current, it is making high pitched annoying noise. I will leave it at 'Moving' for now. I attached a fused 12V supply to it without my car running. What I _couldn't do_ is to use the 'Idle Warmup Duty' and put the max 160 steps in the 60-80F range to make the IAC completely close. Not sure, if this is because the car is not operational?

Great, thanks!

Thanks, NewZed. Appreciate your input. I did arrive at the same conclusion about the cam timing finally - two different things. Appreciate confirming it. I was way overthinking it lol. I think I finally nailed the initial timing config using 0 commanded degrees in the Fixed Timing section of the TunerStudio. I set 60 degrees in the 36:1 section, tooth #1 Angle (deg BTDC), which confirms Chickenman's statement about counting the gaps times 10 degrees for 36 trigger wheels (I have 6 gaps, 60 degrees). If I count teeth, my hall sensor is pointed at the 7th tooth. Question: I checked some of the guys' tunes on this board (cyrgnus and madcaw's) being curious about their total timing on their engines, and most of them have 41-43 degrees by 3000 rpms. I have a stock n/a engine with a N47 head, should i go with a more conservative number like 36-38 degrees?

Found some posts suggesting to use 0 degree fixed timing, this way I am avoiding any issues with timing light/wasted spark results. I don't have any timing marks (-10 to 10) besides the timing pointer I got with the trigger wheel. Tested with 0 degrees fixed advance and 0 degrees cranking advanced using 2 timing lights (old school with a variable knob on the back and the modern electronic one set at 0), both showed the TDC. My 36:1 Tooth #1 Angle (deg BTDC) was set at 60 degrees.