Throttle Lag Summary

Higher octane fuel will help to alleviate, but not fully eliminate, throttle lag or downshift delay.

More detail on higher octane.

Higher octane allows the engine to operate in a Taller gear ratio at a low(er) RPM without "lugging", knock/ping.

So with a higher octane when you initially re-apply pressure to the gas pedal shortly after/during the lift-throttle upshift the transaxle may (more often) remain, briefly, in the "taller" gear ratio since the ECU "knows" that will not result in a seriously detrimental level of Knock/Ping. The ECU would therefore allow the DBW system to immediately begin raising engine RPM, generating additional drive torque, as a result of the new, re-applied, gas pedal pressure.

So now the engine RPM is no longer at idle and should you continue to increase the pressure on the gas pedal such that a downshift is required to keep the engine in a proper, non-lugging, operating range there is now much more likelihood that there will be be enough ATF pump pressure/flow volume to accommodate the upcoming downshift.

The above might also be an indication that a fairly s..l...o....w re-application of pressure to the gas pedal after a FULL lift-throttle event might often alleviate the downshift delay/hesitation regardless of octane. Whereas a quick/fast/heavy re-application would almost always result in a serious level of knock/ping absent an immediate downshift.

Counter-intuitive, huh..??

Go SLOW, to GO QUICKLY...!!

Okay...??

Furthermore I suspect that the new variable displacement ATF oil pressure pump just announced for the Ford Edge will be a final solution for this problem once implemented across the product line. Actually it would be even nicer if all manufacturers of FWD vehicles would adopt this solution.

Multiple sets of Ford repair/shop manuals, going all the way back to a 64 T-bird, Same for many Toyota/Lexus vehicles going back to the 92 LS400, annual subscribtion access to techinfo-toyota.com, and finally, the entire information bandwidth of the internet.

Oh, over 55 years of DIY shade tree mechanicing, beginning with Farmall, John Deere (poppin jonny) and Ford Ferguson tractors. First car was a 1956 Ford Fairlane, then 58, then 63 T-bird, then...Ran most of my Fords of the late sixties to mid-seventies for well over 200k miles.

No Ford ever let me down.

Current Ford ownership is 93 Ranger PU, 92 & 94 AWD Aerostars (which should have NEVER gone out of production), E-350 V10 based MH.

Shame they didn't have the good sense to build those early Lexus vehicles or at least immediately clone them.

Was just in TN/AR in early October for Tyronza all-year school reunion and the Memphis Blues ball. Pat Kerr Tigrett was a summer sweetheart over in Clinton/Savannah in the late forties.

Maybe Alan Mullay will open the eyes of a few of those moribund Ford design engineers.