MSefi.com read only forum (Jan.15,2018)

MSII v3(only a year old) running latest version megatune, 4.6 Ford V-8, running fuel and spark EDIS-8 from MS.

Engine starts, runs, idles drives just fine. There is some weird condition under boost, I stab the throttle, the boost spikes up way higher than the actual pressure being produced and it goes way rich (I know for a fact as I have a analog boost gauge that has been tested to compare with). In the acceleration wizard, the bar chart showing the tps rate of change spikes with a minimal push of the throttle. I've even set the tpsdot to the highest setting with no effect.

I've had this exact engine/blower combination and Megasquirt running very well before, but this is a new ECU I built a year ago and have had these problems.

I've done a lot of testing and trouble shooting and the results are the same. The really odd thing is I had imported an old msq that I had originally tuned for this engine and it worked, but told me I had multiple errors and that's when I started having the false boost readings. I tried to start from scratch and build a new msq file and typed everything in by hand. when I tried to up load it, I get a message battery voltage too low (which it is not). some how the software does upload it anyway but the TPS won't respond correctly and the monitors for most of the sensors don't respond. If I upload the old msq, it takes the upload and works fine except the boost issue.

I'm sure it's a software/hardware/version conflict and I wouldn't be surprised as there are so many versions and variation and patches now, I have no idea what to use. i've even download the complete package from DIY auto tune onto a new laptop that never had MS on it and the same results.

Could you post a data log of this and a copy of your MSQ?

will do

Here you go, hopefully someone can see what i'm talking about. I won't be shocked if there are things that are wrong, but it does run pretty good except for the accleration problem. I did the data log after a 100 mile cruise tonight. Thanks for any input.

Your TPSdot acceleration enrichment is set to spray a lot of fuel. 20% TPSdot is equal to taking five seconds to open the throttle, and at taking a full second to open the throttle, you're adding nearly 12 msec of pulse width. Your MAPdot AE is looking a bit more reasonable.

Also, keep in mind that analog gauges have a lot more damping than the MAP sensor. The boost spike in the log is less than 1/2 second long - it may be too short for the analog gauge to get all the way to the top of the spike before the boost starts dropping.

Thanks for the input, I'll try messing with it some more. I still think the boost pressures i'm seeing are excessive and in error. I've run the table all the way up to 150 and still been able to max out the boost pressure (the engine is incapable of those pressures under no load conditions). It's almost like there is some kind of feedback from the map and tps signals. Under static conditions - key on, not running, the tps on the accel enrich bar and map signal reacts normally (using an external air pressure source), but when it's running, things go haywire.