Hello Everyone,
I have lurked around this site for many years but i am finally at a place where my problem is driving me up a wall. My car is a 1987 T2 with a modified turbo (not sure exactly what as the prior owner just said hybrid but no real paper work) and a street port as well. I have upgraded the fuel pump and currently running 720cc primaries and 1600cc secondaries. It always had problems and last year i finally went to a MS3pro evo from DIYautotune. It made the car actually run and had good power after some tuning but I was never able to see the car reach 100 kPa but chocked it up to being at 6500 feet since the analog gage I had in the car read 10psi. Turns out the baro and MAP sensors were not properly calibrated throwing off the numbers. not the car is showing boost exceeding 100kPa but seems to be falling on its face the second it hits 100kPa. I have tried adjusting timing and fuel but its still like a trigger point and I just cant figure it out. I am so close to a good running car...

 

did you check your over boost protection.

 

Overboost was set at 240kPa and I even turned it off to make sure it wasn't causing the problem. It does feel like overboost spark cut though.

 

any lost sync codes?

 

I am still trying to understand the sync codes. There is a number of sync codes and reason. The number varies and the last I saw was 53. The reason is always 0. When trended, it is just a constant instead of happening when during an event.

 

You shouldnt be getting any lost sync with the engine running in all rpm conditions. Sometimes you will get an odd one during shut down. In the ms3 manual there is a chart with the codes and causes. Run your car and log lost sync reason and lost sync counter. This would be a good start.

 

you probably getting sync erros are you using the stock CAS.

 

Stock CAS. What is odd, is that when the baro was not calibrated and returned 102 kPa, the car ran great but never showed 100kPa in boost. I don't have any logs showing the car starting but once started the lost sync trend is constant with no variation which leads me to believe the lost sync is due to something while cranking.

 

while cranking sometimes you could get a sync error and ones the car start you should not see another error.

 

also i would use falling edge for ignition capture

 

I think this is what is happening in this case with the lost sync. I will know for sure when I find some time to start and run the car again (without waking neighbors). It seems to me like I missed something in the setup somewhere that is causing the issue since the car runs great when it thinks its not in boost.

 

i always use falling edge and never have problems .also ground and 12v straight to the battery.

 

I can see about changing to falling edge. I have a dedicated ground already and new 12v wires ran. But why would this only be a problem when the car thinks it is in boost?

 

did you run a lost sync log yet?

 

I haven't had a chance to run the car again yet but the logs I have show no change in lost sync total for the duration of the logged timeframe. This includes during the issue time period.

 

I figured it out. The car had way too much fuel after boost and was unable to account for it in autotune.