johnrx2

my car is running a lt10s i bought it all built by previous owner. when i first test drove car he showed me the how to turn on ac . he has it set w a toggle to send aux input when ac is turned on.
during warm up the car will lean out and die when i kick it on. if car is fully warm idle will drop to 500 then then bac kicks in and bumps it up to 1250. a few times coming to stop light it has died on me.
after reading a little and looki g at the m t manual i add fuel in the enrich aux map. and bumped up the number that controls the bac opening for more air. it helped imediatly .
can i get this car to idle w ac when cold . somewhat like a normal car?
also it seems like there is a delay for it to raise idle.5 seconds or more.
can i play w the aux timing at idle only or will it mess up my timing through all maps?
car runs great otherwise e85 500 whp . thanks for any help
john

johnrx2

any one have ac running correctly w microtech and bac valve?

johnrx2

bump

Aaron Cake

iTrader: (1)

Also add timing when the A/C is switched on.

But without an idle valve, the load from the compressor is very high and the Microtech has no way of compensating for it.

johnrx2

which map would add timing to the inptiming map? if i drive w ac on in boost would it add timung to all maps or just idle?
idle valve is that the bac im running or diff?
thanks for your reply
john

Aaron Cake

iTrader: (1)

Do you do have the BAC option fitted to the Microtech?

You'd add timing to the idle map below the bin at which the car typically idles, and take a few degrees out of that bin. That way you've created a little timing bump to catch the engine should the RPMs drop.

With the BAC option fitted the Microtech can then control the idle. Unfortunately I don't have experience with that feature as I've never actually seen it in person. In theory you should be able to adjust the duty cycle (I believe the function is AUX_AIR) higher when the AC is enabled.

If the Microtech then waits several seconds to make the change...well, that's just stupid.

johnrx2

yes it has bac valve fitted and working. its on a toggle. so i turn on ac then hit switch and then microtech kicks on valve . it wrks but has died a few times . it seems take a 3 to 5 seconds to kick on to raise idle. if car is cold it wont idle. if car is fully warm it will normally wrk ok w no prob. but like i said i had a few times where it did die on me. fully warm the car idles around 1050-1100 rpm. so would igo to t rpm and take a few degrees away at 500 rpm. ?

Aaron Cake

iTrader: (1)

Yes, take a few degrees away at your idle RPM, then add a few degrees above and below the idle RPM.

You say the BAC is wired to a toggle and not the Microtech? It should raise the idle WAY more if connected to just a toggle...To around 4000 RPM.

johnrx2

there is a screen where you can chose idle speed mine is set at 1250 when the ac is switched on. microtech controls the bac. maybe the toggle switch just tell ecu switch it on. i did not wire car.

Aaron Cake

iTrader: (1)

The compressor trigger wire should be wired to the Microtech instead of a toggle so that the Microtech can raise the idle when the compressor is switched on.