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

I have a megasquirt 2 assembled unit running my chevy 350 Tuned Port Injection. I have set it up for HEI. I have been trying to iron this problem out with no luck. It basically falls on its face when you press the gas quickly but if you slowly accelerate its fine. just quick pulses on the gas it almost kills the engine completely. I have attached a Tune file and the data log. The data log shows me pressing the gas quickly and what happens during and afterwards. I have looked over everything with no luck. can someone take a few minutes and check them out. Any help would be great.

AE needs tuning, right away I notice you have huge MAPdot and TPSdot thresholds.

Ya I know I tried auto tuning it at idle with no load and that spot where it chokes out wont go away. I dont know if its a sensor malfunctioning or the tune itself. I kindof lost motivation when i couldnt get it to smooth out. I have had this runing before with this megasquirt and it was smooth. But when i turboed the engine I had to change maps and then it started this bs. is there anything in the timing that looks messed up?

AE cannot be auto-tuned... Sounds like you need to go over the manual some more

looks like flooding same way my was, lean out whole VE table below idle kPa level in whole RPM range, als IAC over 160 have You checked Your maximum IAC motor steps Did You calibrated TPS

best regards

nk.

Hahns5.2 gave you some good advice, you should follow it.

If the engine runs fine with the throttle steady or moved very slowly, but stumbles when the throttle is moved quickly, you need to tune the accel enrichments, not the VE table.

If the accel thresholds (TPSdot/MAPdot) are too high, then the accel enrichment won't work, so you likely need to lower these back down to somewhere near the default values (the thresholds should be as low as they can be without falsely triggering accel when the throttle isn't moved).

You can find out how to set the accel parameters in the manual: http://www.megamanual.com/ms2/tune.htm#accel

Lance.

Well i think i made a noob mistake. Since this engine is now turbo'd I have added 80 lb ford racing injectors... I had the accel enrichment adding up to 16ms of pulse width because thats what the stocker 24lb injectors were running. I did a quick fuel injector calcuator and it said at the MAX my injectors should be open 8ms on the pulse width. makes sense but I have cut it down just havent had time to test.( raining the last 2 days). If you look at the accel enrichment in the msq u can see that there was up to 16ms of pw added on accel.... ;/ im an confused person but I'm slowly learning. even with all the problems ive had getting this engine goin right I still think megasquirt is bad behind!

I know i have read the manual and I go over it and over it. Alot of things are different between tunerstudio and megatune, i have tunerstudio. alot of the % are in volts and other things. I have leaned things out on my ve so we will see what happends. I had megasquirt for years on my un turbod jeep and you would be suprised at what you forget when you havent tuned anythig in a while.