marches Posted January 20 Report Share Posted January 20 Greetings, ECU is in a 80 Porsche 911 SC - direct spark, cam and crank sensors. Crank sensor ( trigger1 ) shows signal, Cam sensor shows none. However, the cam sensor ( trigger2 ) shows Status signal, but the scope does not see pulses. Cam sensor is Hall, have tried with/without pullup resistor, Edge as rising and falling, never can get pulse from Trigger2. Since the ECU is not getting a sync, no spark during startup. Wondering if the weak(?) signal from Trigger1 is not meeting the Arming Threshold, therefore ECU does not provide spark. Quote Link to comment Share on other sites More sharing options...
aerace_fab Posted January 20 Report Share Posted January 20 can you check the air gap for your crank trigger? Quote Link to comment Share on other sites More sharing options...
marches Posted January 21 Author Report Share Posted January 21 After a bit of search result crawling, I bet you are spot on! Will verify alignment with reluctor wheel and the gap between sensor and wheel. Thanks! Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 21 Report Share Posted January 21 I think you have done the trigger scope capture wrong, that appears to show a stationary engine so I suspect you probably hit the capture button before you started cranking. Try again and make sure you only hit the capture button when the engine is cranking - not before. You can see at the top of your screenshot trigger 1 state says "test gap" which means it has started seeing teeth and it is looking for something that looks like a missing tooth gap. Quote Link to comment Share on other sites More sharing options...
marches Posted January 22 Author Report Share Posted January 22 Adjusted Trigger1 sensor, now see ~1V amplitude, almost 1x than previous. Looks like Trigger2 is reporting OK now too. Still will not output spark to set static timing. Noticed injectors trigger initial, but do not seem to continue after the initial turnover. Feels like there is some safety check that is not being satisfied that we are missing. Is there a mode to ask the ECU ( StormX ) to do a self check and look inside itself for mortal failings, of which it cannot have since it is silicon based? PC Datalog - 2023-01-22 11;03;19 am.llgx TriggerScopeLog_012223.llgx Quote Link to comment Share on other sites More sharing options...
marches Posted January 22 Author Report Share Posted January 22 Adjusted position of Trigger1 sensor, now see ~1V amplitude, almost 10x than previous. Quote Link to comment Share on other sites More sharing options...
marches Posted January 22 Author Report Share Posted January 22 updated log file to include engine speed attached. PC Datalog - 2023-01-22 1;26;38 pm.llgx Quote Link to comment Share on other sites More sharing options...
Euen Burke Posted January 22 Report Share Posted January 22 Have you used the Ignition Test function to confirm that the ECU is actually firing the spark plugs? Quote Link to comment Share on other sites More sharing options...
marches Posted January 22 Author Report Share Posted January 22 Yes indeed, that is the mysterious part to me: all plugs spark as we expect in Test mode. The spark looks a little weak to my eye. Do we know if the spark rendered in the Ignition Test the same quality/power as the one should see when the engine is running? Guessing NO, as it is a test mode. Just observing... Thanks all!! Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 22 Report Share Posted January 22 Your last scope shows the crank sensor is wired incorrect polarity. The ecu wont command a spark until it receives a correct trigger signal so it can synchronise to engine position. Swap the +/- wires at the crank sensor. I will need to see a copy of your tune also. Also your MAP sensor is calibrated wrong, it is showing 400kpa with the engine off, it should show about 100kpa. Another thing I just noticed - your oil temp sensor is not working and you dont have a cyl head temp set up. The ecu will need to know engine temp to be able to do warmup enrichment and idle control etc - this is not going to prevent it from staring though. Which ever one of these sensors you decide to use to represent engine temperature will need to be assigned to the function "ECT" (Engine Coolant Temp) - you can rename it to oil temp or whatever but all the warmup tables and many lockouts etc use ECT by default , not Oil temp. Quote Link to comment Share on other sites More sharing options...
marches Posted January 22 Author Report Share Posted January 22 Adam, thanks for sharing your wisdom! Swapping the + / - for Trigger1 got us to spark. Static timing is set now set, motor barely sputters but will not catch. Now wondering if the lack of ECT input inhibiting any warmup enrichment is (part of) the reason we cannot get it to fire. Now have set ECT to the engine temp sensor AnTemp1. Was not aware of the connection between ECT and warm up enrichment - this is an aircooled application so just assumed oil T would be appropriate. Assumed... Now MAP is set to appropriate model and will recalibrate once ecu is back in the car. Have attached log file during attempted startup and the pcl file. Thanks for the insights!! WHaveSpark.pclx PC Datalog - 2023-01-22 2;55;50 pm_we have spark.llgx Quote Link to comment Share on other sites More sharing options...
marches Posted January 23 Author Report Share Posted January 23 We also noticed there seemed to be a bit of backfire when trying to start. Verified timing is within a couple degrees of target, so began to inspect fuel setup. Opened Fuel Table 1 and noticed at (5.1,0) a value of 2: This goes against the mantra of smooth tables... Could this be part of the issue behind the motor not starting? It sounds like it wants to catch, but seems like it is trying to ignite on the exhaust stroke. Updating Fuel Table 1 (5.1,0) to 30 and will try in the car later this morning. Quote Link to comment Share on other sites More sharing options...
Vaughan Posted January 23 Report Share Posted January 23 It looks like your Fuel table has MGP (Manifold Gauge Pressure) on the y axis but the values on the axis look like they are setup for MAP (Manifold absolute Pressure). Also throughout that entire pc log your manifold absolute pressure shows 345kPa which is very wrong. You need to fix your MAP sensor calibration, fix your Fuel table axis and I suspect you will need more fuel in the top left corner of the fuel table. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 23 Report Share Posted January 23 Also neither your IAT or ECT is set up. I would say your spark plugs will likely be fouled also since you have been injecting about 10 times more fuel that you should be the whole time you have been trying cranking. Quote Link to comment Share on other sites More sharing options...
marches Posted February 6 Author Report Share Posted February 6 (edited) Thanks for all of the feedback! Had to stand back, clean up and verify wiring, remove stale gas and refill. Tried to start again last night, now seem to be getting spark on all six cylinders during test as well as when turning the motor over. However, it has yet to start. Trying to get better at reading the logs... See anything obvious in this set?wiring_cleanup_020523.pclxTriggerScopeLog-WiringCleanup-020523.llgx Edited February 6 by marches grrr autocorrect Quote Link to comment Share on other sites More sharing options...
aerace_fab Posted February 6 Report Share Posted February 6 Your Y axis in your main fuel table is setup all wrong also the numbers in there for traditional mode fuel are very high. Quote Link to comment Share on other sites More sharing options...
marches Posted February 7 Author Report Share Posted February 7 @aerace_fab: if you are referring to the screen cap earlier in the thread, please note there have been a lot of mods since the shot of the fuel table. Quote Link to comment Share on other sites More sharing options...
aerace_fab Posted February 7 Report Share Posted February 7 8 minutes ago, marches said: @aerace_fab: if you are referring to the screen cap earlier in the thread, please note there have been a lot of mods since the shot of the fuel table. The latest file you just shared actually. Quote Link to comment Share on other sites More sharing options...
Vaughan Posted February 7 Report Share Posted February 7 Y axis values should be something like 20kPa to 100kPa for a naturally aspirated motor or above 100kPa to the desired boost for a forced induction motor (~3psi to 14.5psi naturally aspirated) Quote Link to comment Share on other sites More sharing options...
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