throttle hesitation?

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Jan 18, 2007 | 10:49 AM

bocephus_3349

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From: riverton u.s

throttle hesitation?

I have a 93 F-150 XLT 5.0 4x4 5spd. Heres my problem. When i depress the gas there is a slight hesitation then when i release the pedal the same thing happens stays at the rpm and then finally falls back down. So is this normal? I know in the other efi cars ive had and drove they all seem to respond like my 383 stroker. When I punch it the rpm's jump then fall right back down. does any else have this type of problem? One little side note when I removed the "high flow" muffler it seems to be a little better. The muffler is brand new and its one of those from hooker. I just have a hard time thinking its from the muffler. The problem as always been there though sence ive owned the truck.

Jan 18, 2007 | 04:46 PM

tripndrag

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I have owned my 87 5.0 since new. When I stab the throttle really fast to the floor and let off (hitting the throttle as fast as you can and getting your foot off) I could stomp mine to the floor and let off and the engine would just rev a little, more of a cough. It always did it from brand new.

It was never an issue, didn't hurt anything just was weird to me that I could put it to the floor and let off fast enough that nothing would hardly happen. When I went to the mass air conversion, same thing, I would get a little rev. When I re-wired the Ford kit to be totally sequential that went away. The motor will rev no matter how fast I can punch the gas, I even tried it with my hand.

I think the only time this would make a difference is if you drag raced, there would be a lag on take off.

Jan 18, 2007 | 06:40 PM

Dragrazor

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From: Miami

TPS? Maybe?

Jan 18, 2007 | 06:43 PM

bocephus_3349

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From: riverton u.s

what do mean by "When I re-wired the Ford kit to be totally sequential that went away. The motor will rev no matter how fast I can punch the gas, I even tried it with my hand. " I just dont understand why it cant be like the old carb motors. When you stomp on it it revs and then when you let off it drops.

Jan 18, 2007 | 06:47 PM

Dragrazor

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From: Miami

e f i /tps!

Jan 18, 2007 | 07:01 PM

bohiaa

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From: Bellville TX. Wof Houston

NO..

My 93 F150 5.0 has good response..

you may want to clean the TB...

I know if you install a larger one it really helps on Throttle responce.....

also you may want to try resetting the computer let it relearn everything.

Jan 18, 2007 | 11:33 PM

tripndrag

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The ford mass air conversion truck kit for the 1987 5.0 truck using a C-6 transmission that I purchased was still not sequential EFI after installed according to the instructions.

I re-wired the injectors after talking with Ford Motorsport to make the system totally sequential EFI.

There has been much debate on this wiring change all over these boards for years. Even though it isn't supposed to make a difference if you change that wiring that is the only thing I noticed that changed in the way the truck ran.

After I did this I could no longer stab the throttle to the floor and let off without the engine reving like I had stabbed it to the floor.

Every speed density EFI 87-90 ford truck I have ever driven had the same hesitation if you stab the throttle, 302, 351 or 460. If you stab it as fast as you can the engine just coughs a little with very little RPM change. Mine did it in the stock configuration for 200k miles, it did it with the new motor with all the new parts and mass air system till I changed that wiring. I don't know what else to say.