My car is stuttering and shaking

[101lifts2]

Originally Posted by Phenix_Rider

My guess would be the engine mounts. At that age, the rubber in them is probably disintegrating. A lot of front engine cars will have a mount that goes over or under the radiator to prevent fore/aft rocking. Since that's the way the engine rotates, it can make a lot of noise.

I was under the assumption the engine more or less runs like crap and misfires, but it could be motor mounts. I just replaced both on my buddies wife's Ford Focus...thing shook like a bitch.

[101lifts2]

Originally Posted by TIGGER

Haha! That's a good one! The thing is baby, you will NEVER become capable of working on your own car until and unless you try! You have to start some where! If you lift the hood, the vac lines are small, black hoses that generally run from the fuel injection system.



On this picture, the guy has painted his "air box" red. It is on the right and is the piece with the large hose/tube coming out of it. The cover is usually held on with a few screws or clips. The clips can be popped with a screwdriver or even a butter knife. If you follow that "hose" to the left, you'll see that it connects to a "valve" which is the throttle body. The throttle body has a couple cables coming off of it and some small hoses which are vacuum lines. From there it goes to the fuel injection system which is that "box" to the left. Also, if you look at the top of the engine, you'll see four wires coming out of it, which are the spark plug wires. I want you to visually inspect them for any cracks and see if they are possibly loose where they plug in to the engine or at the ignition module (the black box between the air box and engine), it's unlikely that your car has a distributor cap. Just make sure that they aren't loose or obviously cracked.

If you are feeling really brave, the throttle body has an idle adjustment screw that can be turned to speed up your idle and possibly end you problems. If you look at the throttle body closely, you will see that the cables are attached to a "wheel". The screw controls where the "wheel" stops when the cable is released which controls how fast the motor runs when you aren't pushing the pedal (idle). Now all you have to do is turn that screw 1/4 turn clockwise increments and see if you situation improves. I would do this with the car running but if you are uncomfortable with that, just turn the screw a 1/4, start the car. If it's better good, if not try again. I would not go over one or two full turns. If this doesn't help, I'd try your Asian friend. The steps I have outlined to you are basic and will not harm your car in any way. If adjusting the screw doesn't help, keep track of how much you turned it and just put it back.

You really shouldn't tamper with the min. idle set screw on fuel injected cars. I know that Mazda had issues with their early 1990's Protege's. We would bump it up to 700 cause the idle was pretty shitty on some, but there was no other fix nor was there an issue with the vehicle. Usually, cleaning the throttle body would do the trick. Also, I doubt an air filter is going to do anything. But as periodic mantenance, it should be changed at certain intervals, though.

[101lifts2]

Originally Posted by Tsunami

101, if I replaced the plugs and the wires 6 months ago, can it be bad already?

you don't think its the air filter? I just got my oil changed on Tuesday and they supposedly looked at the air filter and shook it out, and today especially when i came to a stop, it was just shaking all over the place!

Ugghh i hate not knowing anything about cars. I have the manual but its kind of hard to troubleshoot when i have no idea what to look for.

No on the plugs, but it could be the wires IF the engine is actually misfiring. When you get on the gas, does the shaking go away? Like its only at idle?

Originally Posted by Tsunami

Totally missed that. Isn't Corona a couple of hours away? I remember driving by there last year and thinking, Oh 101 lives here!

Las Vegas is about 3.5 hours away, unless I take a bike..then about 2. lol

[Tsunami]

Originally Posted by BobTheBiker

let me ask something simple, that nobody else has. do you have a check engine light on the dash lit up? if so, have autozone pull the codes and see whats going on. THEN fix the problem rather than grasp at straws.

No check engine light.

[Tsunami]

Originally Posted by 101lifts2

No on the plugs, but it could be the wires IF the engine is actually misfiring. When you get on the gas, does the shaking go away? Like its only at idle?

theres a delay and a stutter when i get on the gas from the stop but yes it goes away once i start going.

The shaking / rocking starts again when i come to a stop and it got really bad at idle yesterday. It is intermittent though. yesterday it got pretty bad, today there isn't any rocking but there is still a sputter/delay when i first get on the gas.

Actually yesterday after all the rocking and such at one point (and it was a bit cooler during the day, don't know if that makes a diiference) when i started it up to go home, i got on the gas and at about 30 mph and there was a surge and all of a sudden it was smooth again for the next 3 miles until i got home.

Checked the air filter, it looks pretty good. none of the wires seem to be loose. I put decent gas in it, either at the Chevron, Shell or Circle K. Oil and tranny fluids seem good.

[BobTheBiker]

Might not hurt to clean the trottle body, and do a fuel filter. my aunts kia sportage does this at idle too, although I just dont give a shit cause tht thing leaks oil and needs 4X more work than its worth.

[Amber Lamps]

I still like the vac lines or the fuel filter.

[Flexin]

Where is the mass air flow sensor on this car? If its near the air box I would check for the intake pipe after the sensor. Look for cracks or breaks in the pipe. This will allow air in that isn't measured by the mass air flow sensor which would cause it to act up. In some gears it could remain closed and cause no problems. In the lower gears you can have a lot of movement with the engine, this can cause a break to open up and let in more air.

James

[derf]

Originally Posted by TIGGER

I still like the vac lines or the fuel filter.

I just fixed my focus for a similar issue, eventually I found 2 vaccum leaks, one vac line wad a solid hole, because the tube was dry rotted and cracked, replaced that, but then the studder was still there randomly, eventually I was able to find that the valve cover breather was off the valve cover and enough gook had settled on the vac line to make it rub and wore through, but the grease was caked on thick enough that it would seal the vac line causing it to be an intermittent problem.

[Amber Lamps]

Originally Posted by derf

I just fixed my focus for a similar issue, eventually I found 2 vaccum leaks, one vac line wad a solid hole, because the tube was dry rotted and cracked, replaced that, but then the studder was still there randomly, eventually I was able to find that the valve cover breather was off the valve cover and enough gook had settled on the vac line to make it rub and wore through, but the grease was caked on thick enough that it would seal the vac line causing it to be an intermittent problem.

That's where I'm at myself.