engine misfire? Can you help me fix it?

Good morning,

The 302 is a misfire for cylinder 2. I would check the compression to be sure there is nothing wrong with the cylinder.

https://www.2carpros.com/articles/how-to-test-engine-compression

The 316 is a misfire in the first 1,000 RPM's when it started It indicates a bad ignition coil.

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

1504 is for idle air control. A common failure for the idle air control valve.

Roy

So I have been having this “jerk or surge” problem for two months or so now. Just a few weeks ago I have noticed that my car jerks only when the A/C is turned on. I have driven it with the air off, when I get to a stop, I turn on the air, and the car lightly kicks as if it tries to push forward, the jerking and kicking is very random but only happens when I am at a stop. I have changed the mass air flow sensor, idle air control valve. I have cleaned the throttle body and replaced the throttle position sensor. nothing has work. Any guesses? I need help please!
My car is the SE model.

It sounds like the engine is misfiring. Have you done a tune up lately? And should also run the codes to see if anything comes up.

Here are a couple of guides to help us fix the problem:

https://www.2carpros.com/articles/how-to-tune-up-a-car-engine

and

https://www.2carpros.com/articles/engine-vibration-at-idle

If you could take a quick video and upload it of what the car is doing it would help me see what' i going on.

Please let us know what happens.

Cheers, Ken

I put in new spark plugs about six months ago, have not changed any of the coils nor my fuel filter either. The problem with taking a video is that the jerking is so random and you would not really be able to hear or see anything within the car, but I will try to capture anything and submit it. So do you recommend just getting a full tune-up?

Or get my codes checked first, since I forgot to mention that there is no check engine light?

This is all I could get, turning on the ac and having the car jerk and stutter right after, I don’t know if you can notice

Here is this one with the AC at max:

Thats for the videos, It think the AC system might be low on charge causing the compressor to start and stop causing the idle fluctuation. Can you lift the hood and see if this is the case. This guide will show the compressor clutch you will be looking at.

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

Please let us know what happens.

Cheers, Ken

Low on charge? As in it is low on refrigerant? Or? I am confused. And my air blows cold, blows through all the vents, works fine, so the guide does not really pertain to me.

If the compressor is cycling it will. Can you hear the compressor click on and off? If not then this will not have anything to do with the problem. Then I will be leaning toward a vacuum leak or a worn MAF sensor.

Here are two guides to help you see what I am talking about:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

and

https://www.2carpros.com/articles/how-to-replace-a-mass-air-flow-sensor-maf

These problem will affect mixture which will make the engine run poorly at idle.

Yes, when I turn the AC on I hear the compressor click on, what does that tell me?

Could it be a fuse? The AC clutch relay?

It click on yes, but then does it click off again and then on and then off? This is a sign of a low charge even though it is cold. I just want to make sure it not the compressor causing the issue.

No I do not think i have heard it click on and off while driving and having the AC on. what does happen though is that whenever the car jerks, the AC seems to power down or just minimize for a split second on every jerk, you get me? So if it is not the compressor, what could it be?

So when you say there is no check engine light do you mean there is no light with the key on engine off?

No I mean there is no check engine light present at all. Can you still read codes with no check engine light present?

This is another video I took, this was on park, it kept jerking and it sounded like the AC clicked.

This is one of the engine with AC on MAX.

I cannot see it having a problem. can you get a video of the actual problem? I need to see whats going on.

Turns out it was the spark plug cables, easy fix. Wow

O man, sorry we did not mention that earlier, you do a great job with the videos.

Use 2CarPros anytime, we are here to help. Please tell a friend.

Cheers, Ken

I noticed car idling rough and jerking on acceleration. Mechanic said water in gas. Tried bottle of heet; didn't work, check engine light came on; code read misfire #3; mechanic replaced plugs, wires, upper intake gasket; used some fuel injector cleaner; cleaned throttle plate. A little better but stlll when slow down and then accelerate back up it chugs; runs smooth otherwise except same day we got it out of shop check engine light came back on. took it back to mechanic--he says fuel injectors need cleaning which will cost another $300. I hate to keep throwing money at it trying to find what's wrong--but I'll need to get it through emissions in a few months- Help please!

Could be an injector that is going bad, working intermittently.Sounds like everything else has been replaced, except the ignition coil and injector, both of which I have seen cause misfires on these cars.Cleaning the injectors seldom lasts.

I have a 2002 Ford Taurus with the 3.0L OHV engine. I have been experiencing a missfire ever since purchasing the car. I have replaced so many components I'm down to a valvetrain issue. I just did a running compression on two of my cylinders and both were not even reaching 30 psi. When I revved the engine the compression dropped way down to barely being registered on the gauge. Is this evidence of weak valve springs or no? Also, the CEL is not being illuminated but the Mode6 data from my PCM indicates a small misfire on all cylinders (the last time I checked it).

dry and then wet compression test should be done 1st ,compare reading
running compression test not so sure

I did a dry compression test several months ago and everything checked out. All cylinders were within 15 psi of each other. The running of the vehicle hasn't changed since then I just decided to finally take a stab at checking the running compression. I can do a wet compression but it would be this weekend before I could do it.

Don't rely on a running compression test... OK with that out of way when do you feel it miss firingthe most. High load. Light load. Idle? Maybe all the time