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Old 12-10-2011, 01:04 PM
Blown353 Blown353 is offline
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Quote:
Originally Posted by supremeefi View Post
Very Good info 353 , but sometimes when it's too lean on decel it backfire and burble as well. And as mentioned, timing can be a big part of it too.

Keep us posted Mathi and good luck.
Good point-- I forgot to mention that as well. That's what I get for posting in a hurry from work. LOL!

A mixture that's far too lean during overrun can cause the mixture not to burn or not completely burn in the cylinders and instead the unburned fuel will build up and burn/pop in the exhaust.

It does take a little trial and error to find best amount of fuel to greatly reduce or eliminate the overrun pops. Datalogging will at least show you which cells you need to concentrate on for mixture, timing, and O2 correction limit tweaks.

Going too lean in the overrun areas can also cause a "dead spot" in the pedal at very slight throttle angle changes when transitioning out of overrun.

I still wonder why FAST hasn't added a DFCO function after all these years... it's not something that's necessary but it would sure be nice to have-- and it seems like 98% of the other ECUs out there offer it.
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Last edited by Blown353; 12-10-2011 at 01:19 PM.
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