I’m running an EMU black on an older Porsche 911 with turbo. Using a couple of these ZF sensors below for crank and cam position.
Car was running well for months then out of the blue, would miss/backfire for a split second at higher rpm and under load.
Not boost cut, fuel cut or ignition cut etc… no where near those limits.
Log showed that Cam Sync Tooth was dropping out for a split second and also showing a coil dwell error. As time has gone on, it has become easier to provoke it to miss/backfire.
In the software, the 'Disable Cam Sync above rpm" was at the factory 20000… so we lowered it to 2000. Now, the engine runs smoothly with no hint of miss/backfire.
This suggests that the cam sync is the issue, but what do make of the dwell error?
Has anyone used these sensors and had issue?
They are running of the 5V produced by the ecu and grounded to ecu sensor ground.
I’m open to suggestions:
we tried changing secondary trigger edge from rising to falling
adding a filter
raising sensitivity
smaller plug gaps (new plugs)
The only thing that appeared to make a diffference, was disabling the cam sync…
Those Cherry sensors do fail from time to time, especially if subject to heat. What air gap are the sensors?
Are you using a crank trigger wheel or the flywheel?
I always have better results with falling edge myself.
The owner of Adapt Motorsport (manufacturer of the crank/cam trigger unit) thinks that I should use 12v to power the hall effect sensor not the ecus 5V. He thinks it might be right on the verge of operation hence the reason why it loses sync at higher rpm etc.
I use China copy of this sensor for CAM, and power it from 12v.
first connection was in 5v - sync loses on 2000…3000 rpm.
on 12 v - 9000 RPM, no lost sync
Thankyou for replying.
Today I am going to run 12V to this sensor. Do I need to change the ground to connect to Ecu Ground? Or can I leave it as connected to sensor ground?
Ok. so today i ‘stole’ the 12v from my boost solenoid and fed it to the cam sensor,leaving the ground connected to sensor ground.
So far, it seems to have cured my problem.
However, when logging, the ‘cam sync trigger tooth’ still fluctuates between 112 and 113… is this significant? I don’t think it did this when it was newer looking at my oldest logs.
I would say that sensor edge is falling close to crank senso edge and sometimes is on one sometimes on another side of it … if there is no vvt i wouldn’t really worry about it
I see the same on my engine since i installed emu black 4 years ago. Never had an issue. It is in my engine as u say Greg…cam/crank sensor edges line up and is either on the one or other side.
I don’t think this has an functional impact…even with VVT. The tooth count is just relevant for syncronistation.
UPDATE - BAD NEWS - THE PROBLEM STILL PERSISTS - CAM SYNC DROPS AND RESYNCS
Took it for a proper drive today. And when UNDER LOAD and at higher rpm, it drops sync for a split second and tries to re sync. If I new how, I would upload a log and tune file but I dont think I can.
If I build up the revs without using any boost, it will easily redline and not skip a beat. It only drops sync when under load and making boost.
In the middle. Cam sync trigger tooth drops to 45 and a lean condition follows, which means there was misfire right? ECU resyncs back and all goes to normal again?
for uneven crank trigger, CAM need only one time - first engine sync. After this, ecu works only on crank trigger.
i think it is some electrical wiring problem
I updated to the latest firmware, and for whatever reason, I do not have the problem anymore.
Have to admit, I am a little uneasy holding 100% throttle and revving past 6000 rpm but the couple times I did it, it did not lose sync.
For the time being, I’m calling this ‘solved’.
