[wolf41]

Have any of you noticed if this happens with your automatic transmission? Around 60 mph I notice that my tach drops about 50 to 100 rpm's. It does it even with the overdrive button in the off position so I know it's not shifting into overdrive. I have an SCT tune in it. I don't know if it's been doing it only since I got the tune or just since i noticed it a couple of weeks ago.

[amustangrocks]

our 06 did that, turned out to be the fuel pump

[billthecougnut]

Mine does it too, it is like the engine drags when you are'nt on the gas. Doesn't happen if you keep the foot lightly on the accelerator tho... I'm beginning to think I need to try the fuel pump thing, since this has come up before for me, and others, and I haven't checked into that issue.

Just to clarify what mine does (if your's does the same thing) I'll be driving along at 60 mph and let my foot off the accelerator, and coast for a while, the engine coasts at the same rpm as I was driving at for a few seconds, then it seems like the bottom drops out from under her, and she almost downshifts (not sure) and the revs drop like 150 (or MORE) rpms( down to like 1500 rpm's) and drag the car down in speed for a few seconds, then after that few secconds, the rpms's increase back to normal (like 2000) and the car doesn't feel like it's being draged by the motor any more. Is this what you are reffering to? Mine does it and it peaves me to no end, but the solution I have found is to never let up of the pedal completley, just to maintain that matching rpm to the trans. It is a total pita, but until I figure it out, what can I do? I feel your pain tho... I've got issues too.

[wolf41]

Originally Posted by billthecougnut

Mine does it too, it is like the engine drags when you are'nt on the gas. Doesn't happen if you keep the foot lightly on the accelerator tho... I'm beginning to think I need to try the fuel pump thing, since this has come up before for me, and others, and I haven't checked into that issue.

Just to clarify what mine does (if your's does the same thing) I'll be driving along at 60 mph and let my foot off the accelerator, and coast for a while, the engine coasts at the same rpm as I was driving at for a few seconds, then it seems like the bottom drops out from under her, and she almost downshifts (not sure) and the revs drop like 150 (or MORE) rpms( down to like 1500 rpm's) and drag the car down in speed for a few seconds, then after that few secconds, the rpms's increase back to normal (like 2000) and the car doesn't feel like it's being draged by the motor any more. Is this what you are reffering to? Mine does it and it peaves me to no end, but the solution I have found is to never let up of the pedal completley, just to maintain that matching rpm to the trans. It is a total pita, but until I figure it out, what can I do? I feel your pain tho... I've got issues too.

Yes that is sort of what happens, except that if I leave my foot on the gas pedal where it dropped 100 rpms or so it stays there without going back up to 2000 rpms. But if I just touch the pedal it goes back up. What in the fuel pump could cause this, it doesn't make any sense. and why only at that speed?
I wonder if I set the ecm back to original and put back the original filter if this problem would still be there.

[amustangrocks]

Originally Posted by wolf41

Yes that is sort of what happens, except that if I leave my foot on the gas pedal where it dropped 100 rpms or so it stays there without going back up to 2000 rpms. But if I just touch the pedal it goes back up. What in the fuel pump could cause this, it doesn't make any sense. and why only at that speed?
I wonder if I set the ecm back to original and put back the original filter if this problem would still be there.

that sounds kinda drastic. maybe it is in your tune. i would return it to stock and see what happens. ours was a slight hesitaion on the highway, followed by a engine light. we thought from a loose fuel cap, but it was the fuel pump. have your trans fluid checked or changed. low on fluid will do funny things too.