Datalog Getting a constant limp mode
- Thread starter mhol1998
- Start date
Not too sure to be honest, I had a severe wastegate rattle on the old turbos and had the wastegate rattle fix on with MHD when I gave the BMW specialists my car for them to fit the 17T's - after fitting I changed the mapping and the car ran sweet but if you give it WOT over 5k I'd get half engine light (did this on the old turbos too).
Pretty normal given you've put bigger turbos on the car, you're exceeding boost target and the throttle is closing to keep it in check. The tune needs to be reworked to take account of the new more capable turbos.
If it was doing it on stock turbos then this can be caused by faulty boost solenoids.
If it was doing it on stock turbos then this can be caused by faulty boost solenoids.
That's pretty helpful - I will replace the boost solenoids first then, best recommendations for the UK to get hold of them? I hear their pretty easy to change...
Looks like a tune issue. Load actual is going over load requested. Get a custom tune.
Is this a 3rd gear log? I am not sure that your solenoids are a problem. What tune do you have on there now?
Looking at the logs more, those wastegates look really tight. I can see the PID tried to pull it down as much as possible and got near 12%, which is near the WGDC floor. I would reduce WGDC base at the setpoints where it is overboosting and/or WGDC adder above 180 g/s. If it needs a WGDC <12 you might have to lower the floor to something like 8 or 10.
Is this a 3rd gear log? I am not sure that your solenoids are a problem. What tune do you have on there now?
Looking at the logs more, those wastegates look really tight. I can see the PID tried to pull it down as much as possible and got near 12%, which is near the WGDC floor. I would reduce WGDC base at the setpoints where it is overboosting and/or WGDC adder above 180 g/s. If it needs a WGDC <12 you might have to lower the floor to something like 8 or 10.
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cant see the lpfp pressure but your hpfp is taking a huge dive as well, its all tune related but cant tell whats causing the dive because you didnt log LPFP.
Yes that is my next steps is going with a custom tune - I have bought new solenoids for piece of mind as the issue was there with stock turbos on standard map, I have had the car running on a very simple MHD Stage 1 Tune which before anyone says, I know is not compatible with my current setup but was trying to iron out any issues with the car before getting custom tunes.
As it goes I wanted to go to Wedge or Doc Vu for the tune so will get in touch soon with this.
As for your comments about the WGDC settings, I am slightly new to the terminologies above but do have a working knowledge so if you could elaborate and explain how I would go about adjusting the above, that would be helpful? When you say PID what did you mean by this?
Yeah I think the car is pulling it back cause with my foot to the floor the throttle position seems to still be coming back - the HPFP seems to be doing what is should low down, the LPFP seems to hold above 60-80psi the whole time from when I am monitoring, but I also have an upgraded stage 2 walbro 450 pump sitting in the boot ready to go in. So as you say, I think it could just be tune related.
100 % tune related but it would be better if you logged lpfp, if ran out of channels replace the trans temp with lpfp for logging
it makes troubleshooting a lot easier because you might not see what the pressure is actually doing as the gauge
doesn't react as quick like the graph does in the log.
doesn't react as quick like the graph does in the log.
I see - well I am currently awaiting a new TMAP sensor as I had a little issue with this so once fitted and I have my solenoids etc on I will try and get another run done and take a 3rd gear log and put the LPFP Channel on and remove channel or something.
