1-2 shift, engine hesitation
 

Hey guys,
I've had this problem with my truck for quite some time now, and was curious if any of you had any ideas of what sort of problem I've got. I have a '97 f150, 4.6L 4WD w/ off road, and towing packages. just about 108000 miles. MSD coils and wires (installed at 105000); denso plugs (also installed at 105000); Dual exhaust, K&N FIPK, rebuilt tranny, and a partridge in a pear tree.
Problem existed before all recent performance mods.

I'm not sure if the problem existed before the exhaust was installed. It was put on when the truck was young, and can't remember back that far!

Here's the problem; When driving fairly light footed, when the transmission drops into second gear, the engine seems to lose a bunch of power briefly, like it's bogging down. Then it revs up a little and runs fine. I think it may be some sort of timing issue, or some miscommunication between some sensor and the computer. All the other shifts are fine.

Anybody else have this problem? is it software?

Thanks for any help!
~Julien

anyone?

When was the last time your fuel filter was replaced? These have a 30,000 mile change interval. I had the dealer search their records for the last time the filter was replaced. The records indicated about 35,000 miles ago. So I just had mine replaced at the dealer and no more hesitation on my truck. My truck has 101,000 miles. I hope this helps.

It's been quite a while since my fuel filter has been replaced. I'll have to replace it in the next week or so to see if that helps. If it doesn't, oh well, I'm sure it's due for replacement anyways, but if it does, nothing like a cheap fix!

Thanks for your reply!

~Julien

You hit the nail on the head. It is timing. Ford pulls timing at the shift points to lower engine torque and increase transmission longevity. The only way to “fix” it is with a custom chip. I’m not a fan of chips. Why would you want to put premium fuel in something that will always be slow and will always get poor fuel mileage.

thanks for the confirmation on the timing, bent6.

I'm curious why it seems to take a split second to "re-time",
per-se, and why it only does it on the 1-2 shift.

Maybe I'm just hitting a really crappy part of the power band, and it's just showing when it's trying to pull the RPMs back up.

Oh well, small V8, heavy truck. I guess i'll take what I can get!

I'll still prolly swap out the fuel filter so I can empth the tank faster! :)

~Julien

re-set the puter so it can learn new shift patterns. it might help

just a thought-