Cold engine acceleration - spits back up through intake

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fordfanboi
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Cold engine acceleration - spits back up through intake

Post by fordfanboi »

I have TBI. My warm VE / accel enrich values are pretty dead on. When the motor is cold, it tends to go very lean and spit back up through the intake when I try to slowly take off from a stop. As it gets closer to operating temp, the issue goes away. I don't want to richen the WUE values too much because it already runs rich at cruise when warming up and would foul the plugs. Will retarding the timing when cold help the issue? By default, MegaTune advances the timing when cold.

Thanks!
MS II v3.0 (2.920), 408ci, Holley 900cfm TBI, Victor Jr, Mech Roller 254/260@0.050 - 0.642/0.578
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Bernard Fife
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Re: Cold engine acceleration - spits back up through intake

Post by Bernard Fife »

ffb,

You probably want to increase the cold accel multiplier in the Accel Wizard. There is more on this here: http://www.megamanual.com/mt28.htm#tl

Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it.” - George Bernard Shaw
fordfanboi
Helpful Squirter
Posts: 74
Joined: Mon Dec 19, 2005 11:36 pm
Location: Central Texas
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Re: Cold engine acceleration - spits back up through intake

Post by fordfanboi »

Lance wrote:ffb,

You probably want to increase the cold accel multiplier in the Accel Wizard. There is more on this here: http://www.megamanual.com/mt28.htm#tl

Lance.
Will give that a shot - TY!
MS II v3.0 (2.920), 408ci, Holley 900cfm TBI, Victor Jr, Mech Roller 254/260@0.050 - 0.642/0.578
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