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Tippy Tippy is online now
Chain fence eating turbo
Join Date: Dec 2008
Location: Austin, TX
Posts: 8,692
Hot restarts - set your MAT air density to be richer as air temp increases up to about 105-110% (additional 5-10% fuel injected. This is also in case of compressor heat runaway!). When you restart, and the IAT is heat soaked, AFR's will be ok once you find the right % increase. Adjust and tune accordingly until good AFR's.

Priming pulse - bleeds air from injector rails and primes the cylinders with fuel when cold when you 1st Turn key to "ON"

Cranking pulse - injects periodically (pulses) during crank and continues to until it starts IIRC.

☆ when an engine is cold, it likes to be rich. Something like AFR's in the 12's or richer. When the engine just fires off, engines generally like AFR's in the 10's, especially when really cold. That's where ASE and the ASE taper down helps a cold engine stay running during those 1st few CRUCIAL seconds once lit off.

ASE - additional fuel after engine fires keeping it running. This is during first so many seconds when cold when the engine needs to be extra rich so the ignition can ignite
the fuel. Based on coolant temp (head temp) and time

ASE Taper - ramping down to normal warmup enrichment based on time and coolant temp (head temp)

So, rich cylinders are easier to ignite than lean. Read up on the original Honda CVCC motor for a great explanation

Last edited by Tippy; 07-04-2017 at 01:03 PM..
Old 07-04-2017, 10:11 AM
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