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Shuddering???!!!

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Old 12-09-2004, 05:38 PM
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CYiannou
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Default Shuddering???!!!

Ok, here's what happened.

I was driving back to Phoenix from California. I was pushing the car pretty hard- 120 was not uncommon. Just as I was getting into Phoenix the car started jerking really really bad. At first I thought it felt like the power was cutting out, like when you hit a speed limiter only stronger. Anyway, I stopped to check the car and everything seemed fine. It drove fine the rest of the way home and gave me no problems. I figured I must have just gotten some bad gas or something.

The next day there was a small puddle under the car. It didnt' smell like oil, but almost like brake fluid. Also the brake fluid warning light started coming on. I checked the fluid and it is right at the minimum level.
Could the shuddering be related to the brakes in any way. I wasn't touching the pedal at all. Any help would be greatly appreciated.
Old 12-09-2004, 07:38 PM
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dualblade
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more likely clutch, as it uses the same reservoir. you probably either have a burst line or a failed master/slave cylinder. where is the liquid coming from?
Old 12-09-2004, 07:59 PM
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CYiannou
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I'm not sure exactly. Somewhere near the left front tire maybe. On that side at least. The car was jerking pretty bad. Could the clutch cause this. A friend of mine said that I might have boiled the brake fluid from driving so fast for so long. He said that could have created pressure in the system that was causing the brakes to engage. Could this be the case?
Old 12-09-2004, 08:24 PM
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inactiveuser92616
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^^ not likely unless you were using the brakes hard.
Old 12-10-2004, 03:51 AM
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what could it be?
Old 12-10-2004, 06:24 AM
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A fuel filter could do that. Running a buck 20 you're needing to flow a lot of fuel through that filter at that RPM. That would be the first thing I would look at.

I had one start to go bad and it would only affect the car at highway speed, just like smacking a rev limiter, I would pull over to look at the car and at low RPM/fuel need the fuel system would "catch up" with the demand of the motor. Gradually as you need more fuel than the filter could provide it would happen again.

The fuel pump would be my 2nd choice.
Old 12-10-2004, 03:19 PM
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CYiannou
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The strange thing is, I wasn't going that fast when it happened. It was once I had gotten back into town and was back at normal highway speeds.
Old 12-10-2004, 03:25 PM
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CO944
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I would focus on the puddle on the floor.
If you were burning up the clutch while cruising it may start
to shudder. ie not entirely disengaging when you were pushing
the pedal. Find where that leaky fluid is coming from.
Old 12-10-2004, 03:31 PM
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CYiannou
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How exactly could just cruising down the highway damage the clutch? Also the clutch is new about 5k miles ago. I don't know if this matters. Another thing. Yesterday I filled the brake fluid resevoir, and today there was no puddle. It only seemed to leak the very next day. The car seems to be driving perfectly fine too.
Old 12-10-2004, 03:33 PM
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CO944
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How does everything break on a car? USE.
It was merely a suggestion. I recommend keeping a eye on that fluid though.
Old 12-10-2004, 04:00 PM
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chregan
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Clutch sounds likely considering where the puddle was. The slave cylinder is in that area. So is the master. Eventually, you will see your brake fluid drop because they use the same resevoir.
Sounds like it's time to crawl under the car and see where the fluid is coming from.
You can't overpressurize your brake system with high speed driving. The brake boost is only used when the pedal is pushed. It's not a pump. And if you were dragging a pad, then you would smell it and your brakes wouldn't work well from the boiled fluid. You'd know it.

Of course, you weren't using the AC, where you? That would make a puddle under your car. In that area too.
Old 12-10-2004, 06:13 PM
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CYiannou
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No a/c. Thanks for all the help everyone. I'm pretty clueless to these things. I'm still trying to understand how the clutch could make the car jerk so hard, or why the clutch would be involved at all while just cruising and not even touching the pedal. Forgive me if I just don't understand the obvious.
Old 12-10-2004, 06:59 PM
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Stan944
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maybe you had an occurance of two unrelated problems: the fuel system, and the clutch/brake fluid (both mentioned earlier)? I woud definitely check for the source of leak of the brake/clutch fluid.
Old 12-10-2004, 08:13 PM
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Probably two different problems. What color is the fluid? That will help you identify it. Pick some up on a paper towel to check.

Once you know that, things will fall into place.
Old 12-11-2004, 02:14 PM
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CYiannou
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The fluid was bluish just like my brake fluid and smelled similar. I am 99% sure that's what it was. The strange thing is, in the last two days it hasn't leaked a drop.

So, steps I should take to try and diagnose the problem (in no particular order):
1. check fuel filter
2. try and find the leak
3. ???


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