why am i instantly flooding trying to start round 0* to -10* outside?

[frododothis]

Calling for help ! having issues with my daily driver 96 suburban. third time lately where i have had the truck running and driving, shut it off and next day its a no start. cranks. fires and seems to flood out? continues to crank but will load up and stop the starter. last time, about a month ago it broke the starter nose cone due to this. i had no issues when it was colder out, and no issues in the above zero temps last week. i have noticed when it acts up it is around a 0* to -10* outside, starting to seem related?. trucks been 411 pcm swapped running a l31 engine with the ht383 camshaft, mid length headers, has the mpfi upgrade running 72 lbs fuel pressure, fuel pump is high flow and was new last summer also, has 72 lbs while cranking. new oxygen sensors, crank sensor is new, cap/rotor/plugs/wires replaced last summer when heads were replaced, icm and coil have been swapped out for testing. im at a loss on why it behaves this way! looking for any suggestions for the tune or elsewhere to look. trucks been running with this setup for the last year, and runs okay otherwise, no issues at all for the last month since it last decided to pull possom for 3 days



here is the current tuneSUBURBAN 2024 SPEED DENSITY.hpt

failed start today no start.hpl

last driving drive to work.hpl

[SiriusC1024]

Can you set fuel pressure to 58psi?

[gtstorey]

Is it 75psi that Alvin has said where injectors start sticking?

[SiriusC1024]

Yes. Guy's seen my response. Seems he set it to 72lb for "reasons" and isn't interested in suggestions to the contrary.

[frododothis]

It has been set to 72 lbs as it was touching over 90% duty cycle in higher rpms when i swapped cam in last summer. i had read of a few guys running that way, as well as i had heard the Westers Garage high flow spider was the factory mpfi injectors but set too 100psi, so i did not think it would cause issues , and not until recent had there been an issue starting at the raised pressure or at the original 62 lbs i had been running the mpfi unit at for 5 years before the cam. engine i last ran this cam in went lean and ended up losing a rod bearing, trying to be preventative on new block. sorry for the late response, its been a busy week on the farm but figured id start over on the mechanical side. i ended up opening the intake to check the spider operation, could visually see not all injectors are pulsing evenly, attempted to do a individual flow test comparison and they definitely aren't flowing the same anymore. finally bit the bullet and ordered a set from ausinjector, and will hopefully no longer have do an 'educated guesstimate' on flow rate on a cranked up spider. hoping its a mechanic failure and not the tune, right now waiting on the mailman and the nice weather coming hopefully soon as we just got another slight sprinkle ( 4 inches) of snow again!

[SiriusC1024]

Set it for 58psi because that's what the injector data is calibrated for. Put on parts that support flow requirements.