problems with synapse diverter valve

[T77911S]

not trying to flame synapse......yet. just want to understand some things about what is going on and what i have been told by synapse.

i have been chasing vacuum leaks for a long time. i finally figured out it was the DV. here is why.
my AFR would do weird things. at steady speeds and various speeds, the AFR migh be rich/normal or very lean. sometimes going lean-normal-lean as steady RPM's would increase. (Note, all AFR readings were done at steady speeds. most test done at 2500 and 3k RPM).
but for the most part my AFR was very lean, in the mid 15's and even up into the mid 16's. it was 16.7 when i got the car.
there are 2 vacuum ports on the DV. i was only using one and the other was vented to atmosphere. as soon as i tied the 2 ports together the AFR instantly went rich. down to the upper 11's lower 12's. BUT, the car ran FANTASTIC. although i was still shooting flames out the tail pipe. (due to it running rich) only problem was, when i let off the gas, the RPM's would drop to near 0 before coming back up, another sign it is too rich.
i pulled the DV off and checked it with a hand vacuum pump. sure enough, BOTH vacuum ports would not hold a vacuum so i figured they were pulling in unmetered air.

here is the problem, or question.
synapse is telling me it started running rich because when i connected the 2 ports together that opens the DV a lot at idle so "pressure" that the turbo is making at idle is going out the DV thus REDUCING the air going to the engine making it run RICHER.
BTW, my DV was vented to atmosphere at the time not connected to recirculate.
they also told me the DV is SUPPOSE to be open at idle/when it has vacuum.


part if the problem i am having with them is i sent the DV back under warranty because the 2 ports were leaking and the inside of the valve body had wear on the sides from the valve movingn up and down.
all they did was replace some O rings grease it an send it back. (missing 4 of the 6 screws that hold the top on). i tested the DV with my hand pump again and now one of the ports (B) will open the valve and hold vacuum. port A will not hold a vacuum and will not open it. (with my hand pump).
so synapse tells me that my hand pump is not adequate to test the DV. he said they use a bigger pump to pull a vacuum on it.
so i told hem thats why when thye tested it it tested good. he still claims my hand pump is not a good test. so i tell him when the DV was new, i pulled vacuum on both ports to see what the difference was and how they worked because they "manual" that came with it told me nothing and that my hand pump would open the valve from both ports and they would hold a vacuum.
then he tries to tell me that the vacuum leaks from the DV would not effect my AFR's.

i was told the DV is designed to be open at idle and with vacuum. i can see it not being a problem when recirculating although i am not sure if it would effect the performance.

[smurfbus]

IIRC, Jfairman has this unit so maybe he could advice on how to use those vacuum ports. But, if you like to use it as a bow the CIS will always run rich after lift off. You cant dial that out so I suggest you route it to the inlet of the turbo and get the real benefits it has to offer for better spool.

[T77911S]

it is.
its routed back to the elbow right after the AFM. i had the other way just for the sound.