Car is jerking very hard when i drive

Is it shifting hard? or is it cutting out and coming back causing the"Jerking"

scan for codes and check fuel pressure it could be either one of these causing this. Auto parts rent gauge, see link.


https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

https://www.2carpros.com/articles/engine-surges


https://www.2carpros.com/articles/engine-misfires-or-runs-rough

The car jerks when accelerating up to 30pmh. I was told it could be the MAF Sensor. I replaced it and the car still jerks.

Lack of acceleration,chugging,hesitating,jerking,bogging,misfiring etc. could be caused by one of the following below

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Crankshaft position sensor
Knock sensor
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
False air leakage.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note:If it doesn't apply disregard it

1999 Ford Contour 4 cyl Automatic 180000 miles

My 1999 ford contour is jerking very badly. It is fine while i am driving for about 30 minutes then it will start to jerk. I've talked to a few mechanics who say that it may be the fuel injector and other's say that it may be the spark plugs. I tried to crank the car this morning and it turned over but would not start.the car did sit for about 2-3 months in the yard with gas in the tank and and some say this may have got water in the tank. I tried a fuel injector cleaner but after i tried this the car quit working. Can anyone help me?

Oxygen sensor
Dirty fuel injectors (cleaning the injectors often fixes this).
Bad MAP (manifold absolute pressure) sensor
Bad TPS (throttle position) sensor
Bad or dirty MAF (mass airflow) sensor
Low fuel pressure (leaky fuel pressure regulator or weak fuel pump)
Vacuum leaks (intake manifold, vacuum hoses, throttle body, EGR valve)
Bad gasoline (fuel contaminated with water or too much alcohol)

Sometimes, what feels like a hesitation is actually ignition misfire rather than lean misfire. The causes of ignition misfire may include:

Dirty or worn spark plugs
Bad plug wires
Weak ignition coil
Wet plug wires

after running for awhile the car starts misssing and finally dies. It cranks right back up and goes for awhile and starts over. Replaced air and fuel filters, oxygen sensor, throttle position sensor. will appreciate any information ou can give us. Thanks

Engine running rough or misfiring can be cause by the following:

1.Defective spark plug
2.Inadequate spark/coil,defective spark plug wire.
3.Lack of compression
4.False air leakage.
5.Faulty fuel injectors.
6.Insufficient fuel pressure.
7.Contaminated fuel.
8.EGR valve that is leaking.
9.Oxygen sensors.
10.Throttle position sensor.
11.Idle air control valve.

Engine Performance problem
1997 Ford Contour 4 cyl Two Wheel Drive Automatic

I have a code that says misfire on two so i put new plugs, plug wires,crank senser,cam senser.Checked compression it was to spec,checkedfuel pressure it was good,checked vacume it was low but steady(16")took injector rail out and crank engine to see if injector was spraying it was took plug out and check to see if it fired it goes, but it still codes mis on two.loked for vacume leak did not find any it only misses on two.

IF you have compression, fire, and fuel, it should be find. Are you getting a good hot blue snapping spark to the plug?

Also, can you feel the misfire while driving? When you removed the plug was it wet or does it appear to be firing properly?

I have a good spirk, it misses at speed one thing, my son started looking for breathing problems so he took the exhaust manafold off and he found that number two cyclinder has more exhaust gas comeing out the port then the other three. I dont know if that means anthing.

Do you mean when it's running? Does it run any different when it's off? Also, how was he able to tell? Did he check engine compression? That is the only thing I can think of is the compression is higher in that cylender, but that would be hard to tell through the exhaust.

Let me know.
Joe

He checked compression before he removed the manifold but not with it off,it does seem to run a little better with it off,he checked it by putting his hand in front of the port before it got to hot and there was more gas pressure comeing out of the number to port then the other three.The gasses comeing out of the number two port got hot so i know that number two plug is fireing but i guess not all the time or not at the rite time. He checked the timeing belt and looks good and tight so he did not think it jump tooth. The plug looks wet

I was driving down the road yesterday with half a tank of gas, and all of a sudden my car started jerking. A half block down the road my car stalled. I pulled off the road and started my car again. It started fine but was idling horribly, with every bad idle the engine jerks hard then almost stalls. Sounds like it's being starved for fuel basically. When driving down the road it sounds as if my car is only running on 2 cylinders or so. The engine wind up is a higher pitch and I can hear a slight rattle as if something is loose although I found nothing loose. The herky jerky pulling continues all the way as I accelerate with a huge loss in power. Getting up to speed takes a long time as well(obviously). I took the spark plug wires off to find oil in the housing. The spark plugs were covered with oil. I got rid of the oil by using paper towels. Because of the oil problem I then changed the Valve Gasket Cover and then I changed the spark plugs. Now it's nice and dry around the spark plugs and no oil leakage. The car is still sputtering and still has a lack of power and takes forever to get to speed all the while jerking back and forth. Tomorrow I will change the fuel pump or at least check it first, however I do not feel that is the problem. I changed the fuel filter a few months ago. What other possibilities are there for the car running the way it is and was the oil around the spark plugs just a separate issue that I found on accident ?

The fuel filter wasn't clogged or bad as i took it of and was able to cleaning blow air threw it with no disruption

If the plugs are wet, then they are not firing but for what reason...

Could you provide me with the compression readings he got?

I had the same issue and my recommendation is to see if your check engine light is on. What it sounds like is your coil pack might be bad which is what happened to mine. The part is about 50-80 dollars and can be easily replaced if that is what is wrong. The computer will most likely tell you that some cylinders are not firing. You might want to try with that for a start.

first i don't know if that was a type-o but the plugs are not wet, just the number two plug.My son and i both ran a hand over the exshaust ports while the car was running and the difference of gasses comeing out of #2 was noticably more.The compression ran from 172-176 with #2 being 176.I am wondering if this could be a lifter problem.

You mentioned that the plug looked wet in the prior posting. The only thing I can say is that the spark isn't hot enough.