Car keeps jerking/stuttering

[Flipx99 5,000+ posts]

Stuttering can be a large range of problems. When my car did it, it was a combination of two things:
1) Vacuum leak in the intake manifold

2) Faulty oxygen sensor

Wouldn't they throw a code?

 

[njaykaplan 10+ year member]

The MLPS goes out often in those cars, otherwise known as the Neutral Safety Switch, but i doubt that would be your problem. I have a mark viii, and mines going out, and it will jerk occasionally because its confused about the gear, and occasionally when i'm cruising will pop itself into neutral for 2 seconds and then pop back into gear. Try to be a bit more detailed when it happens, in my car (same transmission, although yours is stronger) i've had to replace the 1-2 accumulator spring because it was snapped, and that created a really hard shift. Does it feel like your going over railroad tracks at 50? Could be the torque converter, do you happen to know if you use Mercon iii or mercon v in your car?

 

[Flipx99 5,000+ posts]

The MLPS goes out often in those cars, otherwise known as the Neutral Safety Switch, but i doubt that would be your problem. I have a mark viii, and mines going out, and it will jerk occasionally because its confused about the gear, and occasionally when i'm cruising will pop itself into neutral for 2 seconds and then pop back into gear. Try to be a bit more detailed when it happens, in my car (same transmission, although yours is stronger) i've had to replace the 1-2 accumulator spring because it was snapped, and that created a really hard shift. Does it feel like your going over railroad tracks at 50? Could be the torque converter, do you happen to know if you use Mercon iii or mercon v in your car?

I am betting what Ford calls the MLPS, GM calls the TCC. It seems like they both do the similar things in that the ****** is "confused" about what gear it is supposed to be in.

 

[I Like Waffle]

Drive the **** out of it and see if it gets better. Also, get some marvel mystery oil, thats always worked good for me for cleaning out carbs and fuel injectors and such.

 

[LazyRider 10+ year member]

The MLPS goes out often in those cars, otherwise known as the Neutral Safety Switch, but i doubt that would be your problem. I have a mark viii, and mines going out, and it will jerk occasionally because its confused about the gear, and occasionally when i'm cruising will pop itself into neutral for 2 seconds and then pop back into gear. Try to be a bit more detailed when it happens, in my car (same transmission, although yours is stronger) i've had to replace the 1-2 accumulator spring because it was snapped, and that created a really hard shift. Does it feel like your going over railroad tracks at 50? Could be the torque converter, do you happen to know if you use Mercon iii or mercon v in your car?

Doesn't feel like going over train tracks it just starts like jerking and when I step on the gas and accelerate it stops. I'm not sure about the transmission fluid I haven't had to add any since I've had it.

 

[njaykaplan 10+ year member]

I am betting what Ford calls the MLPS, GM calls the TCC. It seems like they both do the similar things in that the ****** is "confused" about what gear it is supposed to be in.

I think the fords have a TCC as well, but i'm not sure. I was just given a book larger than any school textbook i've ever seen about the lincoln mark viii, which has the same 4r70w transmission, and i'm reading through it and trying to learn how to diagnose my own car before i have problems. Btw, i got this mark viii for 800 dollars and already got my moneys worth over the 2 months //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif.

 

[njaykaplan 10+ year member]

Does it happen specifically when its shifting from say 1-2 or 2-3 or 3-4? There are a lot of minor problems that are easily fixed with these trannys, if you have anyone that knows car mechanics close to you, it shouldnt be bad to fix.

 

[NDMstang65 10+ year member]

Throttle position sensor can also cause the ****** to get confused as well..where it wants to kick down into passing gear but jump back up into over drive...

Take the car through town and just run it in a gear like regular drive or 3 (whatever that may be not sure on the car model) and see if it still does it...

I'd point towards the ****** sensor and/or the TPS...

 

[PioneerSPL1990 10+ year member]

check the fuel Pump wires i had a rotten one in my 1994 mustang when i would get on it , it would studder or almost cut out.

 

[Stephen_c 10+ year member]

Throttle position sensor can also cause the ****** to get confused as well..where it wants to kick down into passing gear but jump back up into over drive...
Take the car through town and just run it in a gear like regular drive or 3 (whatever that may be not sure on the car model) and see if it still does it...

I'd point towards the ****** sensor and/or the TPS...

x2

or idk if that car has a distributor or coil packs. if it has a distributor check the rotor and cap, if not check the coil(s).

 

[John3000 10+ year member]

a marquis?

Tis my bad, did not have my coffee this morning. //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

 

[LazyRider 10+ year member]

Found the problem. There was a leak in the intake manifold. Looks like coolant is leaking down into where the spark plugs are. Car started smoking really bad yesterday and I popped the hood and looked and sure enough there was fluid leaking and it was causing smoke. Did some research and found out that the manifolds in these cars aren't very good and are pretty much cheap plastic and this happens a lot. Just posting this in case anyone else has the same problem.

 

[nativeboy 10+ year member]

yea im having the same trouble with my car jerking and such but i replaced basically what you replaced and still doing it...

 

[skull50016]

i would say check your tire balance, i had a similar problem, the car would shake back and forth and feel like it was gonna break, i would say take it to like pepboys or something and get them balenced

 

[gnatnoop 10+ year member]

EDIT- LOL, didnt see you already figured it out...