I am going to install Vems on Renault 4cyl, 16v engine.
Most of them have 60-2 primary trigger pattern.
- VR, HALL is very common.
- measure for each sensor: if you find 2 pins that measure same resistance in both directions (typically between 300..1400 Ohm), that is VR sensor. Otherwise HALL.
Collect some info (specific engine code, year, ...)
Engine is F4R730, Clio RS 172, year 2000. Specification is:
- primary trigger - VR 230 ohm resistance (same value in both directions?? Please confirm, 60-2 trigger pattern
- map sensor - Vdo 20-100kpa, 520-4780mV
- camshaft phase shifter - on-off type, 7.5 Ohms
- injectors - marelli, hiZ, 14.5 Ohms
- Iat sensor - ntc, 1500 Ohm at 25C
- Clt sensor - ntc, 2200 Ohm at 25C
- engine is standard, only decat, compression ratio 11:1, max power at 6250 rpm
V3.8b (oid11249 v3/11837) has arrived.
1. BOARD ASSEMBLY
I have some doubts about flyback, sck pullup on V3.8b board and main supply.
Flyback
Can you help me and define which solution is applied when V3.8b is purchased as preassembled with 30V flyback?
I have found two solutions. I am not sure which is right.
1. Only 1K5E30V diode from flyback pad to ec36/pin23.
2. 1K5E30V diode + capacitor (light red one wima mks 4 4.7 uF 100 - 10% which comes with recue kit, probably noise filter but i am not sure) between flyback pad and ground
http://www.vems.hu/wiki/index.php?page=MembersPage%2FCsotiF%2FGenboardassembly
That is correct:
Is ground reinforcement essential or optional?
Optional. v3.8 has 54um (copper thickness) so unless the IGBT-s or the injectors are stressed to the extreme (>16A simultaneous), the onboard traces suffice without added wires. Good harness is needed in any case.
About sck pullup on isp header. Is it optional or essential on V3.8b board? It didnt came soldiered on board.
SCK has no effect if the v3 starts up (always on powerup) and communicates. Without SCK pullup (and 47uF or bigger electrolyte capacitor on 5V) it might happen that (say) once in 20 startups it goes into "ISP" mode (not normal running).
Can you check the bottom of the ISP pinheader ? On v3.8b the diagonal resistor not needed, 4k7 near the pinheader. Try to measure with a 100k pulldown resistor applied temporarily to SCK, SCK voltage should be >4V.
Is main supply on V3.8b preasembled? Diode and ptc fuse were soldered od board. It seems nothing else is needed.
Should be preassembled, yes.
OK. Thanks.
Transient suppressor 1k5 / 18V
Between GND and EC36/pin23: it is NOT BY399 but a transient supressor
- protection: it has no effect if the EC36/pin23 "flyback" is connected properly to the injector common+ (+12V).
- However, should the flyback return wire be forgotten (or accidentally disconnected - eg if connected to the wrong side of the fuse and fuse breaks), this might save the FETs (preventing more than 18V + 31V on the FET drains) and other components of the mainboard (FETdriver, processor)
2. WIRING
Engine bay is too hazardous-very hot and possible leaks from cooling system, moisture... Ventilation bay is populated with battery, air filter, ventilation fan and lots of moisture. The most convenient place i found is under the front passenger seat. But wires will be 3 meters long in one direction!!! Will this be a problem-voltage drop, noise...?
Should be good under the front passenger seat.
- 3m should not be a problem (if the rules are followed, and shielded cable is used for triggers, shield connected only at the ECU end).
I managed to place ecu closer, so wires are about 2 meters long.
3. TRIGGER SETTINGS
Q Finally I put all parts together. F4R engine is assembled. V3.8 is alive, but I have problems with VR trigger.
It almost sounds like HALL sensor is connected to VR input.
At first there was good signal only under 150rpm, with default arrangement (R30 27k). Lots of missing tooths over 150rpm. Then i removed R30 and put 47k series (pullup ?) on VR input line. Now signal is perfect when cranking (managed to check TDC with strobe light during cranking), but when RPM goes above 250 (engine tryes to fire) there are trigger errors, and engine wont start. When RPM falls bellow 220 signal is clear again.
This is very abnormal for a VR sensor (which outputs higher amplitude and more stable signal at higher RPM).
- Either there are some magnetic disturbances (like the Audi 7A flywheel)
- or something fundamentally wrong, like VR polarity, or not a VR sensor at all.
- wiring loom is done with shielded cable, grounded at ecu side, grounds done according to manual.
- VR sensor resistance is 230 ohm.
- please measure DC voltage on EC36/pin27
- resistance between trigger1 ec36pin27 and lm1815 pin3 is 18kohm.
- sensor polarisation is not as it states in renault manual, wires need to be swaped
- firmware version is 1.2.31
- VemsTune version is 1.5.33
- captured triggerlog showing both good and bad ?
- most likely scopeshots will be needed in this case so amplitudes and signal shape are seen