Cemicks Posted January 2, 2021 Report Share Posted January 2, 2021 Discovered recently on dyno pull rough mid range. It looks like Inlet cam is not moving. I cleaned manifold and inspected the solenoid pin connectors to board as they are a weak point. Solenoid bench tests fine with magnets as I hear the solenoid/valve clicking. I also applied 12v to pins 2 & 5 and supplied a ground to the IA, IR, EA, ER pins and also get audible clicking. I am attaching two log files with the car warm. One is increasing rpm and trying to hold steady to activate the cams. The other is idle with several throttle blips. Looks like exhaust cam is moving as it should as it moved 30deg....questioning the %DC signal. It went from 57% to around 0% with lots of fluctuation. Looks like the Inlet cam moves 1deg but the solenoid %DC goers from -57% TO +57%. Do you think I am chasing electrical or mechanical? I purchased a pressure gage to measure VANOS pressure but need fittings in order to test it. Should I cut into the solenoid signal wires and verify the voltage changes at the connector as the ECU signal shows? I have a new (used) solenoid that I can modify again removing the diodes to see if in fact the solenoid is faulty. Any suggestions Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 3, 2021 Report Share Posted January 3, 2021 Yes, exhaust looks like it is working ok, but it looks like the DI offset is about 20degs off so when it is all the way home it is still showing -19deg. Inlet offset is probably wrong as well which would explain why it is showing 22deg all the time - it is probably actually home, and should be reading zero. But when you do target more than 22deg, we should see it move - we can see the ecu command positive duty cycle to the solenoids but we see no cam movement. So that could mean a mechanical problem or wiring problem. You can check the wiring by putting Aux 1 and 2 into "Test PWM" mode with the engine off to see if you hear them clicking. FYI, to explain how the duty cycle parameters work with the S54 high pressure vanos: There are two solenoids on each camshaft, one advances the cam, the other retards. Positive duty cycle means the ecu is commanding duty cycle to the advance solenoid, the retard solenoid is closed. 0 duty means both solenoids are closed so the cam is held in position. Negative duty cycle means the ecu is sending DC to the retard solenoid and the advance solenoid is closed. 57% is the max commanded flow for this VVT mode. Quote Link to comment Share on other sites More sharing options...
Cemicks Posted January 3, 2021 Author Report Share Posted January 3, 2021 I performed the Test PWM on all four solenoids. Had to change from 50Hz to lower value to hear it. I had no clicking on Aux 1 Inlet Retard. I started moving the wires going to the connector and it started clicking. It appears the socket was not contacting the pin. Was able to adjust the mpin slightly for positive contact even with jigging the wires and connector. Attached in new log with active Inlet Aux 1 retard. Regarding your comment about Exh Offset off 20deg. When it is all the way home it should be showing 0deg like the Inlet? Log 3-01-21 2;14;09 pm Warm w-vanos solenoid fixed.llg Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 3, 2021 Report Share Posted January 3, 2021 Yeah, both cams are working now, I still think both offsets are wrong though as they dont move as far as they should. To determine the correct offset, you need to perform the cam angle test on each camshaft and use the lowest number returned from that test as your offset on the DI and under the trigger 2 VVTi settings menu, instructions for the cam angle test are in the help file page: VX ECU Tuning Functions > VVT Control > Tuning VVT Control >Cam Angle Test. Use a test pulse count of 7 when doing the exhaust cam and use 6 for the intake cam. 1 hour ago, Cemicks said: Had to change from 50Hz to lower value to hear it. What frequency where they set to originally? 50Hz is what they should be set to for the S54 according to the help file. Quote Link to comment Share on other sites More sharing options...
Cemicks Posted January 3, 2021 Author Report Share Posted January 3, 2021 Yes both were set to 50Hz. I will proceed as directed with the cam angle test. These are not stock cams....does that matter or am I determining the proper offset based on the cams in the motor? Do I run the test at idle? Currently looks like DI1 VVT Cam Position Inlet Offset is 344.0 deg ATDC and Trigger 2 VVT Exh Offset is 383.0 deg ATDC. Are you saying they should be the same value? Based on the lowest value from the cam test? Again, thanks for your help. I have certainly learned a lot over the past few months. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 4, 2021 Report Share Posted January 4, 2021 8 hours ago, Cemicks said: hese are not stock cams....does that matter or am I determining the proper offset based on the cams in the motor? The cam angle test forces the cams to the home position then you set the offset so that home is "0" cam position. Just like setting your base timing. 8 hours ago, Cemicks said: Do I run the test at idle? As per the instructions I said to read, you need to run it above the RPM lockout. 8 hours ago, Cemicks said: Currently looks like DI1 VVT Cam Position Inlet Offset is 344.0 deg ATDC and Trigger 2 VVT Exh Offset is 383.0 deg ATDC. Are you saying they should be the same value? Based on the lowest value from the cam test? No, you test one cam at a time. For example, do the LH exhaust test, note down the lowest cam angle and that is your offset for the exhaust cam. Quote Link to comment Share on other sites More sharing options...
Cemicks Posted January 7, 2021 Author Report Share Posted January 7, 2021 Cam Angle test complete. Please confirm my direction from the attachments. Inlet Offset should be 112.5deg replacing 344.0 and Exhaust Offset should be 44.2deg replacing 383.0. So then the max movement (as long as no mechanical bind or anything) is based on any mechanical stop installed in the Vanos for these 292 cams. I am still trying to track down what mechanical limiter was installed as I have email evidence that the Vanos was modified. Thanks Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 7, 2021 Report Share Posted January 7, 2021 Correct. Our data shows the inlet offset is normally around 115 and exhaust around 25, so those results look much closer to what I would expect. Enter them in and check cam position follows target. Quote Link to comment Share on other sites More sharing options...
Cemicks Posted January 7, 2021 Author Report Share Posted January 7, 2021 3 minutes ago, Adamw said: Enter them in and check cam position follows target. Sorry, what do you mean by "follows target"? Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 7, 2021 Report Share Posted January 7, 2021 Target is the angle in your VVT table that you are commanding the cams to move to, position is the actual measured position. If everything is working right the position will closely follow target. So if the target is say 30deg you should get a position of about 30deg (+/- a couple of degs). Before when it was targeting 0 on the exhaust you were getting -20. You can view this on a time plot/graph, or just the runtimes screen like below. Quote Link to comment Share on other sites More sharing options...
Cemicks Posted January 7, 2021 Author Report Share Posted January 7, 2021 Excellent. Thank you. Garage is 4C right now so tomorrow after work I take it the next step. As we say in America......its Miller Time. Quote Link to comment Share on other sites More sharing options...
Cemicks Posted January 9, 2021 Author Report Share Posted January 9, 2021 I made the cam offset changes but am getting lots of cam errors. Position is following target. When blipping the throttle i start to hear a mechanical screech which obviously concerns me. I only let it do this momentarily on a few occasions to catch it in the attached log. I had to go back and select log all parameters as my first attachment was specific parameters. The vanos is supposed to have mechanical limiters which I am still trying to confirm. I am sure the previous owner was not relying on ecu limiting. I record a 4th cam pulse error on the exhaust. I also notice every time I turn off power to the ecu the new cam offset values revert to the old values when i turn back on. I send tot he ecu but am not getting any confirmation when i do it. Log 9-01-21 11;28;45 am.llg Vanos Offset Change 1-9-21.pcl Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 10, 2021 Report Share Posted January 10, 2021 Cams look like they are controlling correctly now. Inlet error is not counting up so that is fine. Exhaust error is continuously counting up so that could do with a closer look. I would suggest trying some of the other cam angles from the cam angle test as your offset, it has unevenly spaced teeth so you will probably find one of the offsets will give less errors that the others. For the mechanical issue there is nothing much I can offer, you will have to diagnose that yourself. 16 hours ago, Cemicks said: I also notice every time I turn off power to the ecu the new cam offset values revert to the old values when i turn back on. Are you doing a store (F4)? Quote Link to comment Share on other sites More sharing options...
Cemicks Posted January 11, 2021 Author Report Share Posted January 11, 2021 Thanks, I will try other angles. Funny the mechanical sound (as I'm calling it) does not occur with the original offset angles , just the new ones. I did confirm there are stops on both vanos pistons. Both stops are installed to reduce Retard position. I happen to have a stock vanos for comparison. I was not using F4, I was doing Store to ECU under ECU Controls. Quote Link to comment Share on other sites More sharing options...
Cemicks Posted July 3, 2021 Author Report Share Posted July 3, 2021 Just an update. Car is fully dyno tuned now. I found a top notch ViPec tuner here in the states also intimate with BMW S54. Two days of calibration and dyno tuning. Now have oil pressure, oil temp, fuel pressure all added to the ECU. I then provided 20 minutes of track logs and we adjusted active fuel map and overrun fuel cut to reduce some mid range richness and popping when I went full throttle to no throttle. I head to another track this week and will provide one more log to see if any more adjusting is warranted. Can’t thank this support forum (Adam) enough for helping me out this past winter figuring out VVT issues. I’m sure I’ll be back but for now. Time to drive b HuxRacing 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.