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Discussion Starter #1
I'm getting this bad vibration in the car that happens every minute or so. it idles a bit rough and the steering wheel is constantly vibrating, then all the sudden a big vibration that sometimes makes the hood raise slightly.
this happens mostly in gear and is worse in reverse. I got out and looked under the hood, and from out there you can't really tell anything is happening, the engine doesn't sudden change sound or move, and you really can't heaany change when outside the car.

I noticed when I turn my wheel while sitting still that it makes this vibration gets super worse at spots as the wheel is turned and my headlights dim.
I have no clue what is going on here, it seemed to start after I changed the motor mounts.
I've checked everything that I know of, connectors, vacuum lines I changed the plugs, cap and rotor and nothing is fixing it. please help! thanks!
 

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I agree w/ Allthumbs since I had that problem long ago after changing all 3 motor/trans mounts. Also some aftermarket mounts have rubber that is stiffer than the original . I replaced my "new" aftermarket mount under the radiator with an OEM one, centered the engine again and the vibration was gone. You need to verify engine RPM to see if the engine is bogged excessively by the tranny when this happens.
 

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Yes, and the clue is: It seemed to start after I changed the motor mounts. Have seen this a bunch of times of the mounts not being centered correctly causing a bad vibration , which is actually the metal side of the mount grounding out on the bracket. All mounts, as Rickorino states must be centered, and make sure you don't have a defective /broken one either.
 

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Discussion Starter #6
my Haynes manual states that the mounts have slots in them to adjust for the axle length, but neither the mount I took out, or the new one has them. it is just a round hole, so there is no way for me to move the actual mount side to side.Is there another way to center it?
 

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Discussion Starter #7
the mount I referred to without the slots is the right motor mount. I wanted to add that I changed all three at separate times. it seems like this problem started after going the last one which was the trans mount.
 

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On my Spirit, the passenger side and the front mount were slotted. The transmission mount allowed sideway movement without having to be loosened. I remember the front mount allowing sideways and front to back movement of the engine.
 

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Centering the engine is a MUST when changing mounts. I'll bet that's your issue. And not centering it can cause the CV joints to fail, long-term (as in months).
 

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Discussion Starter #10
I do have the slots at the front mount , and the trans mount does allow for the side to side movement, but that passenger mount does not.

I measured the axles and one is dead on, the other is about a 1/4 off to long. It said to do this with the alignment set, but my camber is way off thanks to a bonehead mistake on my part.

Could that account for the 1/4 inch?
 

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Discussion Starter #11
I discovered today that I had a vacuum leak at the map sensor, along with a gas leak st the fuel delivery line. could either of those caused the engine to vibrate every so often?
Sorry for all the questions, but I'm new at this, just trying to fix things myself cause I can't afford to take it somewhere. I need a new timing belt, and have a leak in the trans seal which I can't even attempt to do, but changing the mounts and the axle seemed pretty easy, till I started having all these problems.
 

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Vacuum leak at the MAP sensor will definitely make the car run rich and stumble at warm idle. Fuel line leak is extremely dangerous and can result in fire at any time without warning. That must be fixed immediately.
 

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Discussion Starter #13
I got the fuel leak fixed. The clamp on the supply line was loose..
Problem with the map sensor hose leaking is with the new hose I put on. The original is a smaller diameter at the sensor than at the manifold end.. it split and I couldn't find a new hose like that so now the new hose is a bit too large at the sensor end and leaks.it was fine at first for about a month but must have stretched or something. For now,I wrapped a wire tie around it, do you know where I can get an oe hose?
My dealer doesn't have parts for my car anymore.
 

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Yes, MAP sensor can definitely cause that, too. I swapped out a failing MAP sensor for the wrong one once and the car bucked like a bronco just at idle.
 

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Discussion Starter #15
So how do I adjust the engine since I don't have the slots, and why is one axle within specs, but the other not? The one on the side with no adjustment is the one that is the correct length.
 

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The bracket on the passenger side mount that bolts down to the frame rail should have oblong slots, but it won't be obvious because of the large washers covering the holes. These bolts are vertical.

I found it somewhat difficult to shove the entire power train more than about 1/4 to 1/2 inch, so you may need to improvise with some wood blocks and a prybar.

Regarding your camber adjustment, this may help:

If your steering wheel was centered before you changed the axle AND you never changed the toe via the inner tie rod, you may be able to get your camber setting closer to the way it was by experimenting (trial and error) with adjusting the strut bolts. Loosen the nuts on the knuckle to strut bolts and adjust the camber cam bolt. Sometimes you can see the original position by matching the cam shaped washer on the head of the bolt to the washer outline or clean area on the strut bolt hole. Try to make the adjustment as close as possible to the original, tightenen everything back up and see if your steering wheel is closer to being centered. This only works if you just distrurbed one side and is not a substitute for a professional alignment....but may get you by while you are working out the other issues. Eventually you will need to bring it in for alignment, and when you do, be sure all the steering joints are tight (i.e. not worn out). The common wear items are inner and possibly outer tie rod ends, and rarely the lower ball joint.
 

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Rick Burton said:
So how do I adjust the engine since I don't have the slots, and why is one axle within specs, but the other not? The one on the side with no adjustment is the one that is the correct length.
I would say it's because the camber is off.

The adjustment is made by loosening the motor mount bolts and prying the engine with a pry bar until the measurement is correct, then tightening down the bolts. It's generally a two-man job, one has to hold tension on the pry bar while the other tightens the bolts.

But I believe the camber will have to be fixed first to get an accurate adjustment.
 

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Discussion Starter #18
John,
that's just it,I don't have the oblong holes, just one round one. the picture of my mount online has the same thing, no oblong holes. I thought maybe I got the wrong one by accident or something.

my car hasn't been aligned correctly since I got it and the wheel is way off center. the bone head mistake I made was taking apart the knuckle to strut as you suggested, but not making the cam bolt. So I learned a lesson there.
do first thing on my agenda is to take it for an alignment.
I don't know if this tells you guys anything or not, but the vibration or pulsing is only happening when the car warms up.
 

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Discussion Starter #19
I'm finding all kinds of stuff wrong, the new plugs I put in aren't the correct gap. They have me the wrong ones.Would that cause any of this vibration or weird idle?
I can't change them till tomorrow to find out.
 

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What did they give you, and what gap? For the 2.5L 4-cyl, you want Champion RN12YC gapped to .035 inches. Anything that is not an equivalent will mess you up. Even at that, Autolite and some platinum plugs cause a rough idle in these engines.
 
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