Without car in hand I can’t say if you need mounts or not but the symptom you describe could also point to a bad CV joint or possibly even an engine performance problem.
On level ground put trans in fourth gear and push it back and forth with hood open so you can watch engine jump around wildly. Then you will see the effect of bad engine mounts. If you have automatic, put it in park and try it. This isn’t as easy with an automatic but maybe it’ll work.
You can also have someone put the car in drive and gently push the gas pedal with the brake on while you observe the engine with the hood open. Then do the same in reverse. The effects of bad motor mounts will be apparent as the engine will flop around. (a little movement is normal) If you can look under the car, you can check to see if the transmission is moving around too–you could have a bad trans mount. If the engine stays put, you likely have a different problem, such as a “driveability” issue in the engine’s sensors or electronics.
yeah it really doesn’t move when I do any of those things. The trans mount is also mounting the engine though. It did move a lot before I replaced the other two mounts but not anymore.
Have them diagnose the issue without putting your 2 cents in first which will taint the diagnosis.
They won’t proceed with work until you approve the estimate and accept diagnosis. They will charge a tad of time to diagnose which is typically in repair price but if you choose not, be prepared to pay a diagnosis fee.
Living with a clunk likely will turn into something more severe, cars old or new are not supposed to do that.
This all seems pretty simple. The OP wants the car fixed. The dealer wants to fix the car and not have a dissatisfied customer. The dealer’s,mechanic has probably seen enough of these,problems to know the cause. The dealer’s service dept is in business to fix cars, not sell motor mounts.
They’re replacing the mounts as we speak so we’ll see!
When motor mounts go bad they sortof get “Hollowed out” and allow the engine and trans to flex or twist under load. The only thing I have seen this do is cause noise and or dent the hood while the engine tried to jump up out from under said hood. They dont cause violent jerking…pretty much ever.
Now are you sure you arent experiencing a misfire on the engine? A misfire could be observed to cause jerking in the car. A failing transmission can also cause a jerking sensation while driving. This has to be weeded out…Just saying its motor mounts kinda scares me…bec I dont see how mounts would cause what you are describing.
Blackbird
Well it does it in neutral so wouldn’t that indicate it’s not the transmission? All the mechanics say the engine is fine and they don’t see any misfires.
Well they replaced them and absolutely no change. Now I am asking for them to put the old ones back in and give me my money back.
just got a full refund. They said “maybe” it’s transmission now. Now I really don’t know what to do.
I guess I, and some others were wrong about the motor mount diagnosis. I wonder if it is something about the lockup feature of the torque converter. On many cars, this feature can be disconnected. If the jerk is no longer present, you’ve found the problem.
What is a torque valve. Google is failing me. Is it also called something else?
How violent is this jerk? Have you checked your transmission fluid? How about your ignition system - plugs, wires? Are you sure the jerk isn’t an engine miss? Is the check engine light on?
Check engine light is not on. I had the transmission fluid flushed. It was dark brown. It has remained a good red color since it was flushed and it’s not leaking. I’m not sure it’s not an engine miss. I changed the spark plugs but not the wires, I could try that.
How violent is the jerk? Does it happen frequently enough in neutral that you could get out of the car and look under the hood while it’s running and see what’s happening when it jerks?
I don’t know if this is relevant, it’s only happened twice, but two times when I have started it recently it emitted a very large amount of thick white smoke from the muffler. It lasted about 10 seconds then went away.
The jerk does not change the momentum of the car, it’s not something that would make my head move. I feel it like someone just punched the inside of my car. It’s like a thud. It’s very hard to describe and google for unfortunately (believe me I have spent hours googling it). Jerk is probably not the best word and thud would mean it’s audible but there is no noise.
It’s like this, in any car, you can floor the accelerator, let it off abrubtly, then immediately floor it again. If you do this you will feel the engine struggling against changing so fast, it “thuds” sort of. That is the exact feeling but it just does it when accelerating or decelerating normal. Yes, it started doing it when accelerating now too which is new. Seems like it’s getting worse.
I’ll try to look under the hood when I have someone to help though. I did with the mechanic and he couldn’t see anything moving.
Great that the dealer refunded you the full price. Did they have any comments?
b
No they didn’t say much at all really just said it might be my transmission and that the motor mounts needed to be replaced anyway. They put the old ones back on that’s how I got the refund.