I had wondered about the cranking advance, but the base timing is set right around 0. Then its compensated for in the MS to set base at 10 once the 5v is supplied on the timing wire. Stock base timing is 10, but mine is set to 0 because at 10 the rotor strap doesn't line up with the posts on the cap and causes a mean misfire. Its a brand new dizzy too go figure. Also, even with the cranking advance where it is it catches as soon as I turn the key and fires up, it just stalls shortly thereafter.ihateforums wrote:You can still have false readings, in a situation where a misfire dumps unburned air/fuel into the exhaust and is read as lean.WillExoIX wrote:Its an AEM Uego wideband and I always wait until its warmed up before I start so it should be accurate.
Have you tried a lower cranking pulsewidth? My understanding in that MS1 will do 3 squirts per revolution during cranking on a 6 cylinder. So when you compare the cranking PW to the PW while running, you have to keep in mind that the number of squirts could be different! If you are running only 1 squirt or 2-alternating then I would definitely try a lower PW for cranking.
That 0.9 degrees of cranking advance sounds less than ideal. I'm not sure what your ignition setup is, but I would say double check your settings and maybe verify the spark with a timing light.
Tuning cold starts can be tricky. When the engine first fires, the revs jump up, MAP goes down, fuel in the intake evaporates. Then the opposite happens. Revs start to drop which causes MAP to rise and fuel in the intake to condense. This is when the engine will die if warmup/ASE aren't enough.
2 squirts alternating is how it is setup right now. GM HEI 7/8pin ignition, Hmm, cranking is set to Time based and a 10 degree Cranking Advance Angle. But if it were trigger return I would have to square away that rotor phasing issue cause trigger angle has to match cranking advance.
But with those settings it runs like stock and is as smooth as it was before, so the base timing and the offset (?) cancel eachother out, replicating the stock timing flawlessly. Its an electronic advance as well so no points or vacuum advance.
I have been playing with the ASE, because that is activated right after the car comes out of cranking mode, and ASE is a filter for the WUE analyzer. So I have been trying to get it to stay running after cranking, cause if I don't bring it to around 1500+ rpms it will stall, plus it runs lean for those first 15-20 seconds. So I know I will probably have to add some WUE, then add a little more ASE to see if it will catch itself.
Worth noting again I have no working IAC, and after getting compression back on 6, the idle was dropped from 11-1200 in park to closer to 850-900 in park. So I may need to open the throttle screw a little more cause the rpms will run a little low and I think that also has something to do with it wanting to stall not running an IAC.