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Its only an issue because it will not start when cold. I crank it and it will fire, but shuts down instantly with a whoosh almost like it has flooded. I say almost because the only way it will start after that is if I hold the pedal to the floor while cranking. This is a TBI on an old 4.9 Ford. It runs great once it starts. It has ran great all summer. Now that it is getting colder here it does not want to start. Can anyone tell me what skalar, flag, or table I need to tweak to work through this. I have a Burn 2 and have made many changes to the bin I'm using to get it to run. I have messed around with the choke skalars and flags but to no avail. I either am not massaging the right one or maybe not enough. Any ideas will be greatly appreciated. I tacked my last log and the bin I am using if anyone is curious and wants to help solve this. I am using the 7747 ECM if that entices anyone....Thanks.
Sounds like it may be the crank AFR vs CTS is too rich at the lower temperatures. Can increase the AFR in those areas.
There is also the open loop AFR vs CTS that is used once the engine is running (usually over 400 RPM).
Last but not least there is a crank AFR multiplier vs percent of engine RPM. This table is used to blend the cranking RPM into the running RPM fueling. This table will also affect warm startup.
I believe I got it. Last night In the flag : "Crank AFR During Cranking" I bumped it up 4 all the way around and it started and ran right off the bat this morning. 36 Degrees. Still takes about 4 cranks to start but its been that way as long as I have had it running. Is there a flag or skalar that can shorten the crank time? My head starts hurting after looking at all the possibilities. My Jeep CJ with a 360 that I TBI'd last year starts after 1 crank. Not because of something I did on purpose, just lucky I guess. On this truck I believe I started with the factory bin AKDY or AKDX, not sure which. I raided my local pick n pulls and picked up 5 or 6 7747 ecms when I was doing my CJ.
The one on the left was what it was....right is what it is now.
I believe I got it. Last night In the flag : "Crank AFR During Cranking" I bumped it up 4 all the way around and it started and ran right off the bat this morning. 36 Degrees. Still takes about 4 cranks to start but its been that way as long as I have had it running. Is there a flag or skalar that can shorten the crank time?
Yes, that original table is quite rich. As for the long cranking, does the fuel pump run at key-on, engine-off? If you used the fuel pump oil pressure switch, that may be what is triggering the pump. Once oil pressure is over 4 psi.
Try this: key-on, engine-off for 2 - 3 seconds. Then key-off for 5 seconds. Then key-on, engine-off for 2 - 3 seconds again. Do this several times, then turn key to crank. It may be that the fuel is draining back out of the lines to the TBI unit.
If so there is a hot fuel module that GM used in many trucks. At key-on, engine-off this module ran the fuel pump for 20 seconds, instead of 2 seconds. So can key-on for 5 - 10 seconds, then crank to start.
Between that and checking the fuel pressure (9 - 13 psi). There really isn't anything in the calibration to help. Although, between the crank AFR table and cranking PW vs RPM multiplier table, can make the first injections larger (PW wise). But that won't help if there isn't fuel at the injectors.
Also, make sure that the engine cranking RPM is decent, there needs to be some engine speed to pull the air/fuel from the manifold into the cylinders.
I can give the key on key off test a try. I did consider the fuel leaking back out of the TBI. Hoping there was some tweak to a table or something that might cut the cranks down. As far as the cranking speed I think its up to par with about as good as it is going to get. It has a new gear reduction mini starter on it. Turns over effortlessly. It was just something I am playing around with.Pretty happy with it so far.
I crank it and it will fire, but shuts down instantly with a whoosh almost like it has flooded. I say almost because the only way it will start after that is if I hold the pedal to the floor while cranking. This is a TBI on an old 4.9 Ford. It runs great once it starts. It has ran great all summer. Now that it is getting colder here it does not want to start. Can anyone tell me what skalar, flag, or table I need to tweak to work through this. I have a Burn 2 and have made many changes to the bin I'm using to get it to run. I have messed around with the choke skalars and flags but to no avail. I either am not massaging the right one or maybe not enough. Any ideas will be greatly appreciated. I tacked my last log and the bin I am using if anyone is curious and wants to help solve this. I am using the 7747 ECM if that entices anyone....Thanks. 
