Kieran

A couple of tanks of gas since the firmware was upgraded to ver 4.9.9, and the CEL light hasn't flickered once. Thanks Scott.

OK, I'll apply the firmware update and re-test. Thanks!

OK, I finally got around to logging this. Attached is an Excel spreadsheet of the log, the rows where knock has been detected are colour highlighted. I can upload the LLG file if you want, but it's quite large at 15MB as I let the car idle for a while in order to capture the symptom.

Yep, I'm using the internal knock detection capability. I'll try to capture the logs.

Hi guys, my ECU (G4 Extreme red) is set to flash the CEL when knock exceeds 500, which aligns with the knock control configuration as it was set up using a pair of known good knock headphones. I've noticed that after the upgrade to FW 4.9.8, the CEL has been flashing intermittently at unusual times, e.g. during cruise conditions - 50-80 kPa MAP, steady throttle, under 3000rpm; or while decelerating on overrun fuel cut. I've checked to make sure nothing has come loose on or around the engine that could be causing noise, the car is a road car so it still uses all of the rubber engine, drivetrain and exhaust mounts. The knock sensor is a donut type provided by Torque Performance to suit the ECU and is about 18 months old. The mapping has not changed and is still operating with the correct o2 readings and ignition timing. So, I'm struggling to identify any potential changes that could have caused this, other than the firmware update. Have there been any changes to the way knock detection is done in FW 4.9.8?

Thanks, tried setting D to 0 but it made no difference to the hum of the motor. I think I'm just over-reacting, as the hum is inaudible from within the car when the interior fan is on, let alone when the engine is running. Having been driving around with the e-throttle for a couple of weeks now, I'm very pleased with the smoothness & linearity of throttle response that I've been able to gain by adjusting the E-throttle target table, while avoiding the inherent dullness of throttle response that is so prevalent in the donor car.

OK I've got the PID settings to the stage now where the throttle plate is accurately and quickly tracking the target, with negligible overshoot. The PID settings I'm using are: P = 6 I = 0.047 D = 27 Max clamp = 60% Min clamp = -60% Deadband = 0.1% I tried adjusting the frequency over the available range and it made negligible difference to the volume of the hum. I've set it at 1kHz now as a 'safe middle ground'. Interestingly, I translated the P12 FSM from Japanese, and its checks on the E-throttle drive circuits consist of checking for a DC voltage on the open / close terminals. One example that was given was at warm idle with all loads turned off, there should be 0.1-015V on the 'open' terminal and 1-2.5V on the 'close' terminal. I wonder if the factory ECU smooths the drive signal to the E-throttle, and if so would it be a wise idea to do the same with the Link? I'm going to try and get hold of another P12 and scope the E-throttle drive signal wires.

Thanks Phil. The throttle plate is tracking target pretty well, I just need to spend some more time tweaking the integral and derivative gains and it should be suitably accurate. When the OEM ECU was connected, I couldn't hear any humming while the plate was being held stationary. I've only gone as high as 2khz on the frequency, and that just raised the pitch of the hum. I'll try some higher frequencies. Cheers Kieran

Hi, can anyone recommend the PID settings for a Nissan E-throttle? It's a 70mm Hitachi unit off a 2001 Primera P12 SR20VE, but I expect that similar vintage units off the VQ35 etc to be the same or similar. I've set the E-throttle up with the recommended defaults provided in the PCLink help file, and tried some basic fine-tuning, but there is still a notable hum from the E-throttle when throttle position is 10% or less, and I don't want to risk burning out the motor.

Incidentally, have you tried using the interpolate function?

If your engine is producing the same AFR despite a >20% change in the fuel map, there are more important things to worry about than "stressing" the injectors! Do you have a link to any articles about "stressing" injectors?

My map used to be smooth, then I got it tuned properly on a dyno and it's now a lot lumpier. Why would you want to add a feature that takes your fuel map away from its optimum?

Hi guys, can you please look at the viability of adding an extra logic item on the aircon controls. On the OEM Nissan ECU's I've dealt with, there are inputs into the ECU from the aircon evaporator that can either be an NTC thermistor (tested and works with an AN Temp channel) or a 12V/NC switch, depending on the model. What would be good to see is the aircon logic having the option to trigger off an AN Temp channel, with hysteresis, or trigger off a DI channel with a selectable ON level. I've tried wiring the 12V/NC switch into the existing Aircon Request DI, but as this DI needs to have its pull-up resistor on, go through a pressure switch on the aircon receiver/dryer and then earth through the button on the dash, I can't get it to apply the required logic.

Hi Eddie, sorry I've been very busy so have only just had a chance to look at your tune now. By & large, the fuelling looks good. The ignition map looks incomplete though, particularly in the WOT region - I wonder if the tuner was checking for knock, as it looks over-advanced at WOT & high rpm. The dwell settings look backwards too, although I suspect that it's not running too little dwell at any point. How did you get on with the other tuner?

I don't have a base map available at the moment sorry. I can have a look at yours if you can get the PCL file though.

Hmm that does seem low then. In comparison, I compression tested a stock SR20VE (10.3:1 static comp ratio) at 230psi. I don't see any reason why NGK leads wouldn't do the trick, as long as they're the right length.

Yep they look like Fujitsubo's. Did you perform the compression test with the throttle wide open and all plugs removed? You can definitely retrieve the pcl file without altering the settings on the ECU, just use the excellent help file in PCLink to guide you through the steps.

Hi Eddie, There's a couple of things that could be causing issues... those Magnecor leads do look like they won't be helping the situation; they're clearly for a RWD SR20 with its taller cam cover. Stock VE leads very, very rarely have problems and aftermarket leads are often a backwards step. So the first thing to try & do is swap back the stock VE leads (if you still have them) or the Nologys, and then see if the miss is still there. Second thing is the Fujitsubo headers - if they have not been modified at all, they are a marginal improvement over stock and will be at their limit at 215whp. Shortening the secondaries to ~100mm works wonders with these headers. The third thing is the ECU may be picking up triggering errors at high RPM - however with this and the idle symptoms, nobody can actually say for sure without seeing the PCL file and a log of it behaving badly. Do you have either of these? Whereabouts are you & your tuner?

I've tuned G4 Storms running both SR20VE and SR20VET. What info are you after? Do you want to post up the pcl file? Link admins - can you move this to the G4 section please?

Cool, thanks for the response Phil.

I'd also like to know why the fuel+ign cut is marked as Rotary only. From memory, the fuel+ign cut wasn't marked as such in PCLink versions prior to 4.6?

As per the quote from the Tunercode vendor in your post, the stock ECU is a fuel-only limiter. This isn't an issue on standard engines, but once you start turning the wick up it can cause detonation when on the limiter. Set your limiter to IGN cut. Consider that a harsh limiter like the factory one introduces some pretty severe accel / decel forces onto the engine, including the valve train. This could in certain situations cause the engine to throw a rocker. If you keep the limiter smooth, then you avoid this scenario and the car should become easier to control when you're sideways and hitting the limiter, as you're giving the engine/drivetrain/suspension/tyres a more gradual reduction (and reintroduction) of power.

Agreed, the Vipec's mixture map feature would be very handy in the Link. The only reason I still use Logworks is to capture the AFR logs in a table format that will approximate with the Link's fuel cells, and provide all the relevant statistical information. Having this incorporated into the Link logging functions, with a direct correlation between the logged AFR cells and the fuel cells, would be a great addition to the Link logging functions.

Have you changed the Ignition Mode to Distributor? Have you performed a 'Test ECCS sync'?

Hi Carl! Just the standard wire-in loom & a inlet air temp sensor are all that's required over & above the standard SR sensors. Since no wiring exists, you'll need to do something about the plugs. My build thread on Nissanz should have some helpful info.