Thud when pressing accelerator

Post by **vtl** » 03 May 2019, 17:32

Square mount has a lot of play in it, by design. Torque rod also has a lot of movement due to soft bushing.

"Thud" sounds like a harsh drive engagement in transmission.

Post by **prwood** » 04 May 2019, 15:25

I have recorded two more videos showing engine movement, one wide angle showing the whole engine bay, the other close up on the upper engine mount. In both of them, I start the car, then shift with the brakes applied from P -> R -> N -> D and back again. Then I repeat while adding some gas while in P and R.

[youtube][/youtube]

[youtube][/youtube]

Post by **vtl** » 04 May 2019, 21:50

I hear a slack in differential and/or in CV axles. Grab the driver side inner CV joint with your hand and try to rotate. If you can turn for quite a bit, and I guess you can, the differential needs a thicker shim. Nothing too bad, I would first address all imperfection under the hood your have filmed for us =)

Post by **prwood** » 05 May 2019, 07:07

vtl wrote: 04 May 2019, 21:50 I hear a slack in differential and/or in CV axles. Grab the driver side inner CV joint with your hand and try to rotate. If you can turn for quite a bit, and I guess you can, the differential needs a thicker shim. Nothing too bad, I would first address all imperfection under the hood your have filmed for us =)

Let’s pretend I’m not aware of any other imperfections...

what would you address?

Post by **vtl** » 05 May 2019, 08:16

prwood wrote: 05 May 2019, 07:07 Let’s pretend I’m not aware of any other imperfections... what would you address?

1. Wiring loom
2. Wiper arm covers
3. Bumper clips

Can't see rubber hoses, but they were bad on all of 3 P2 wagons I had, so replace rubber with silicon.

Post by **abscate** » 05 May 2019, 09:53

That sure seems like a lot of play Peter

Harder for me to compare since I have a 5 speed manual, though,

Post by **prwood** » 05 May 2019, 10:59

vtl wrote: 05 May 2019, 08:16
prwood wrote: 05 May 2019, 07:07 Let’s pretend I’m not aware of any other imperfections... what would you address?
1. Wiring loom
2. Wiper arm covers
3. Bumper clips

Can't see rubber hoses, but they were bad on all of 3 P2 wagons I had, so replace rubber with silicon.

Phew, nothing I haven't been living with for the past few years.

Post by **jimmy57** » 05 May 2019, 12:27

I haven't read through this thread but has anyone mentioned steering shaft slip joint? Early 99 S80s had issues with this but with age and dust and drying out grease that telescoping segment in steering shaft inside car can get stiff. The subframe moves fore-aft with acceleration and braking. That motion moves the rack and thus that section of shaft is where the yield to that motion takes place.

Post by **prwood** » 06 May 2019, 18:56

Checked on the left inner CV joint today. I was able to turn it about 1/2” forward (and back) but that’s all. Is this enough to be of concern?

[youtube][/youtube]

I got a brand new right CV axle in 2017 because the boot had ripped and gone unnoticed until it started dramatically affecting drivability (I’ve got a great video of the old joint I should post some time). The left CV axle hasn’t been serviced and both inner and outer boots look to be intact.

Post by **DeadEric** » 06 May 2019, 21:37

The front of the engine flop during the break revving is concerning. Loose trans torque mount could be suspect. Excessive play in the upper mount could just be compensation.

CV axel play looks nominal.