Question on driveability issues

[c1skout]

Hi, I'm new here. I just bought a 1999 4x4 with 3.0-5spd (vin code V). I was wondering if there is anything that can be done to reduce the amount of time it takes the engine rpm to fall when shifting gears. It seems to "hang" for a second when you release the accellerator when shifting, slowing down the proccess of smoothly shifting to the next gear. I don't have a problem dealing with this, my wife's old Saturn sedan was slow to idle also and we ran that one for over 100,000 miles. I just wish it would drop the revs when I want it to, not a quarter of a second later.
Does anyone know of a way to make the idle drop more quickly?

 

[Wicked_Sludge]

what rpm does the engine turn when you push in the clutch (the computer will keep the motor's idle higher between shifts then when stopped)? a quarter of a second isnt very long...it doesnt sound to me like theres a problem with the truck....

 

[almostclueless]

My 98 does it too, even with a new IAC.

 

[c1skout]

The quarter second was just a guess, I haven't timed it. It seems to hang longer the higher the revs are when the shift is initiated (longer at 3000rpm than 2000). I don't think it's a problem other than being a programming problem. It seems more and more cars are set up this way and it's just one of my pet-peeves I guess. I was hoping someone knew a way to trick the electronics into making the engine behave normally.

 

[almostclueless]

I've tried to evaluate what makes mine do this....it doesn't seem time related, more vehicle speed, like a dashpot function taken wayyyyy too far. Maybe Ford in typical half-assed fashion made the closed throttle fuel curves too lean to get the model/engine/year certified for emissions and had to do this to get the stupid thing to not stall when coasting down with the clutch engaged.


My engine will continue to rev around 1750rpm until the truck gets below 3mph, regardless of how quickly or slowly I'm slowing down. I could probably get it to roll very slowly for 20 seconds and the idle would stay that high LOL.....reminds me of austin powers on the steamroller with the guy in front of it screaming for 60 seconds LMAO. Bottom line, if it's programming, Ford should have done it for a couple of seconds max instead of a speed.


I've been suspecting it's a software issue, as I've replaced the IAC. The speedo works fine, don't remember if there's another speed sensor (I don't have cruise). Never tried to trip the ABS.


I WON'T miss this bullshit when I get my 08!!!!

 

[Earl43P]

c1skout,

Your truck is performally normally.

If you pull the ABS fuse, it will stop doing that "hanging", but you will lose speedometer/odometer/ABS/Cruise Control.

The PCM props up the idle between shifts to aid you making a smooth shift.


almostclueless, You have a malfunction; no way should it hang at 1750. Mine will hang steady at 1000 rpm anytime it's rolling, then it drops to ~700 at almost stopped. Since it isn't your IAC, I'd be looking for a vacuum leak. I'd be interested to know how your truck behaves with the IAC connector disconnected. My thought is even though you REPLACED the IAC, it could still be the root of the problem if you have clogged IAC ports.

I'd also suggest cleaning the butterfly area of the throttle body. It could be sticking partway open when you release the gas. Pretty common.

 

[almostclueless]

My thought is even though you REPLACED the IAC, it could still be the root of the problem if you have clogged IAC ports.

Plugged ports would manifest themselves as a LOW idle.