Hi all -

I did a search on this but could not find anything.

My sister has an Expedition (a 98 or 99 I believe) and it has a problem where it lunges forward when she starts up. At first it only happened on the first start of the day, now it seems to be happening anytime she starts it.

Anyone aware of this happening to other Expeditions?

Any idea what this could be?

Any insight is appreciated!

Thanks.

k

 

How can it lunge forward when it is in park? I'm confused.

 

I'm confused too.

Is it after staring and putting it in drive that it lunges? Could it be that when it's first started and idling higher, she's putting it in gear to quick?

 

it almost seems like she doesnt have the clutch pedal pushed in. but seeing as how these things don't have clutch pedals...im lost

 

I gotta agree that "lunging" while not in gear doesn't make much sense, but here's how she described it:

She starts the Expy and - although the wheels don't turn - the entire vehicle "lunges"...almost as if the vehicle were trying to move but the brakes are holding it in place. She does not put the vehicle in drive...It does this without anything else happening other than turning the key and the engine having started. No touching the brake, no touching the acc. ped., no touching the gear shift. I guess the monion the vehicles is kinda like when you are creeping along and you hit the brakes hard...the vehicle stops but the body wants to keep going so you feel that lurching/rocking motion.





She also states that she can let it idle for a bit and just before the rpm's drop down it sometimes lunges a second time. Again...the wheels don't turn...the vehicle is still in park...no gears changes....it just wants to move but can't because in park/brakes, so it rocks back and forth once.

She took it to the dealer (yeah right) and they said "Oh that's normal"

Anyone else experience this?

 

Mine does that when you first start it on cold days. I figured it was torque reaction as the engine starts to spin the tranny. It sort of torques over and feels like it moves forward a bit.

Ian

 

Ian -
Do you know of any way to correct this?

 

Sorry, I don't have a solution. Mine's done it since new. It only does it on cold days on first start when it has been sitting for a couple of days.

Does your sister have the 4r100? It may not happen on the 4r70. It is definitely tranny related.

I don't see it as a big deal although I can see why some people might find it scary.

Ian

 

It's normal for this to happen. Previous posts are correct, that it usually happens only when cold. I also have a Taurus and it does the same thing sometimes. If she is concerned just have her step on the brake when she starts it.

 

My 5.4L races to around 1,500 to 1,600 RPM when cold then quickly drops to around 1,000 RPM then drops again to normal range of 600 or 700 RPM. I've never noticed a lunging effect.

Now I've seen other people put their vehicles in gear while the engine is "racing" immediately after startup and seen their cars lunge. Maybe this is what is happening to her. Tell her to be patient and the RPM's will drop to the normal level very quickly after start. We've all gotten very spoiled with these PCM controlled electronic fuel injected vehicles and not waiting for them to "warm up" even though it is a good idea to let the engine RPM's moderate before driving.

 

This happens in park when the engine first catches, not when you go into gear. Mine does it even if the parking brake is applied.

It surprised me the first couple of times since I usually just reach in the door to start the truck before brushing the snow off and you can really feel it when you are leaning on the door pillar.

Ian

 

Sounds like that old Audi 5000 problem from the 1980's is reasserting itself in 2002.

However, I don't care what Ford says- If the car "Lunges Forward" when the vehicle is in park, with the foot on the brake, or worse yet, with the parking brake on, I gotta think that- that is NOT normal. Unless someone has a 5-Speed manual Expedition, with the tranny, left in gear.

I've driven everything from a Honda Civic to an Acura 3.5RL, from a 1973 Ford Gran Torino Elite, to a Ford Pinto to a 2003 Ford Expedition, From a Nissan Sentra to a Nissan Maxima, from an M998 HMMWV (Hum-Vee) to a M35A2 Deuce & a half, from 1984 to present, and I have NEVER-EVER experienced anything like that. Not even in GM cars (Sorry, I had to throw a jab at GM).

Pointers:

1.) Never start a vehcile without being behind the wheel, with one's foot on the brake.

2.) Make sure you're pressing the brake, not the accellerator.

3.) Manual tranny's in neutral, clutch depressed fully, right foot on the brake.

Follow those guidelines above, and I won't have to turn on the TV and hear about someone inadvertantly driving through the restaurant, their house, their garage door, over their wife, over thier kids, or worse yet, over the dog.

Remember, safety first!

 

Thanks everyone for their input so far.

Just to clarify...

Yes...she has her foot on the brake...

No...she does not put it in gear. It is in park. She starts it. She does not quickly throw it into gear...she does not rev the engine...just start and let it run on its own. It does the lunge thing shrotly after starting. She lets the engine warm up till the rpms come down to a normal idle.

It used to only do the lunge once, but now it sometimes does it a second time just before the rpms drop..no stepping on the gas by her or anything.

I'm with bighersh any agree...no matter what Ford sez, this anin't normal.

Ian -I'm not sure if it's the 4R100 or not. It's an Eddie Bauer Expy. I know my Lightning has a modified 4R100 and I have never had this problem. I had a 2000 L for a year and this never happened. I have a 2002 L for about three months now and it never happened with this vehicle.

If anyone else has any ideas chime in. It's a mystery to me.

 

Just to clarify to everyone what it feels like. If you are on a slight slope and put the truck in park without the parking brake on, the truck moves a fraction of an inch before the parking pawl takes the weight of the truck. This sensation is exactly like that.

The truck doesn't actually move, it just bounces on the pawl as best I can tell.

Ian

 

Ok, ok mine does it too!

This morrning I went out and cranked it up after sitting fro almost 2 days in sub 30 degree nights. So it was cold.

I cranked it up, and sure enough, it "linged" forward. Now I wouldn't even come close to comparing it to the Audi issue.

So after that, I did a test. I simply reved it up to about 2500 reral quick without my foot on the vbrake, and it did it again, just not quite as much-but still a forward motion.

I think it's simply the torque as it cranks cold. Nothing I'd be too worried about. Maybe in the colder climates it's more noticable. I'll be paying attention to mine now, just because it came up. Prviously it wasn't something that got my attention.