Question about Cars & Trucks
I had a 95 Volvo with similar behavior and I found out it was due to vacum leaks. I made my own automotive stethoscope to find the air vacum hizzing noise made by a broken vacum line or a air intake gasket or seal. You could by one of these stethoscope at any auto part stores
Posted on Feb 13, 2014
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Check Four Things:
Posted on Oct 22, 2008
You have a hesitation. A hesitation is cause be either:
1. bad spark plug
2. bad spark plug wire
3. bad or leaky or plugged injector
4. timing is off
5. leaky vacuum hose
Posted on Mar 04, 2009
3 things; U-joints, (very likely) ,engine or transmission mounts, or mud under the engine or a 4th possibility would be tires (seperated or out of balance ) good luck
Posted on May 01, 2009
It is difficult to give a precise response without seeing the car while shaking. Ihf car has automatic transmission, car shaking at 30 to 45 mph is commonly caused by a late shifting transmission, in some case wheel problems, or an engine problem (less commonly) can cause the same problem.
As said, common reasons for vibration that takes place only at a determined speed include transmission related problems, drive train and wheels related problems and engine related problems.
1 Automatic transmission related problems:
If the auto tranny is shifting too early, then the car will shake. In that case an experienced driver should be able to tell that the car is hesitating because the wrong gear kicked in. This kind of problem is commonly caused by a defective TPS(throttle position sensor). TPS is most common failure causing early or wrong shifting in a determined gear (5th if that happens at 45mph).There are less common transmissions related problems that can cause the same.The mechanic can easily test the TPS using a voltmeter while accelerating on the lift, and eventually replace the part.
Traction and wheels problems:
A mechanic driving the car can feel if problem is caused by wheel. Regarding tires, balancing problems can sometimes give more shaking at particular speed. Even if you think this is not the problem (and probably is not), tyre balancing and alignment is an inexpensive operation that should be done when you get this kind of problem.
In the driveshaft, if the u-joint is worn, loose you get shaking, when problem is starting you may feel the problem only at a determined speed. If the The U-joint may also bind up when you accelerate. The driveshaft can be checked moving the sections of the shaft by hand and checking if it loose or if there is binding. The center support bearing must also be checked.
Engine related problems.
If the problem starts at 45 mph you can exclude failures like a broken engine mount, however, an injector failing or a misfire that takes place only at determined rpm may cause the problem.
Most engine problems leave behind a fault code stored in the PCM even if the CEL does not come on. Better doing a code scan as first thing. Other tests can only be done in the garage, this include connecting machine to injector and fuel pumpt to draw the waveform of pulses sent at different speeds.
I think that I have shared what I could about the possible problems causing the shaking at 45 mph, while in acceleration. If possible try to understand if problem is given by an auto transmission engaging a too high gear, or by engine missing at that particular speed. Do the tires, just in case.
If you repute my solution helpful, please do not forget to accept. Providing good support requires time and skills, and your rating is important for us.
Posted on Oct 02, 2010
Tips for a great answer:
Dec 04, 2013 | Cars & Trucks
Dec 04, 2013 | 1999 Subaru Forester
Dec 22, 2012 | 1991 Honda Accord
Apr 07, 2010 | 1997 Dodge Intrepid
Feb 22, 2010 | 1994 Buick Skylark
Jan 21, 2010 | 1998 Toyota Camry
Aug 18, 2009 | 2004 Audi A4
May 31, 2009 | 1992 Honda Prelude
Jul 17, 2008 | 2000 Volvo S70
37 people viewed this question
Usually answered in minutes!