Looking for some help with my new build. I seem to be having a few issues. Here is the rundown of what setup I have.
93 VW Corrado, OBD2 swapped.
UM #42 tune
DRC 268 Cams
Bosch 044 in tank
Bosch 42# injectors
3 bar fpr
The first problem I am having is what seems to be low vacuum during idle. Only showing about -6 to -7 inHg. I'm pretty sure I don't have any vacuum leaks. I sprayed some carb cleaner around all the joints with it idling, then tried propane and the idle never changed any.
The next issue is during idle the afr will slowly rise up to around 15-15.5 and it will start to idle a bit lumpy, for a few seconds, then the afr will drop back down to around 14.5-14.7. Rinse and repeat at random.
Lastly, and my biggest concern is the in boost afr. It seems to run lean at lower boost pressures, around 7 psi, but seems to be about normal at higher boost pressures of around 15 psi. Also, seems to be lean at lower rpms too, and rich up top.
Here are some logs I did of some third gear pulls. I am spraying water only with the smaller snow performance nozzle.
Here is a photo of the setup.
And a little video.