Firewall Rust

[Rusty09]

I have a 09 SSV with a rust hole in the firewall near the accelerator pedal.
I found the hole after several weeks of trying to understand why my carpet
was soaked.

Holden has advised a repair estimate of $7600
They classed it as general wear and tear.

Any advise would be appreciated.

 

[rambunctious]

Hmmm, The car is 10 years old, what is your question ??

 

[Fu Manchu]

You need to see some of my posts.
Have just completed this very repair.

I believe it is a design fault with the panel. Mild steel and the rust starts where the welds are made.

I got a replacement panel new and checked it over for weak spots first. I then treated it with a high zinc spray.

I was devastated when I found the rust while removing the dash to replace the evaporator in the ac.

It is a big job. Huge.

Remove the entire dash.
Remove the steering wheel
Remove the insulation panels in the engine bay
Remove the wiper cowl and wiper mechanism.
Unbolt the brake booster from the master cylinder.
Unbolt the pedal panel

Not all the insulation panels are made for series 1.
Series 2, you can still get insulation panels to replace the old ones.

If I hadn’t been doing the ac, I would have found out about the rust by having the brakes go through the fire wall at an intersection.

I am yet to do a write up on the jobs involved. There is almost no info on doing it yourself.

Suggest replacing AC evaporator and heater core at same time because you don’t want to do this again later.

*The photo of the firewall inside and out is after I did the repairs and spraying.

 

[Calaber]

Fu.
It's a damned shame that plate is so complicated to remove, seeing that it's actually a separate removable component. I suppose the consolation is that it IS removable rather than part of the firewall or floor pressings. From your description of the work involved, you would have to weigh up whether to have the car repaired or junk it if it was close in value to the cost of repair by a workshop. . Tough call if its otherwise a good car or a top spec one.

 

[Dayvo]

Is the rust visible from under the bonnet or inside the car or do you have to first remove some components ?

 

[lowandslow]

Jesus Christ. 10 years old and you get that? Poor form.
Can you check for it easily?

 

[wetwork65]

Jesus Christ. 10 years old and you get that? Poor form.
Can you check for it easily?

Or you can buy a brand new ZB and have hidden rust immediately https://forums.justcommodores.com.au/threads/holden-warranty-rust.276799/

 

[Fu Manchu]

This panel goes in with the whole HVAC system in one go during assembly.

In VF, the same panel is made from a high density plastic, however it is a totally different shape to the VE. This to me, suggests Holden were well and truly aware of this issue.

I think every VE owner should get in there and check behind the insulation.

It was when I had to remove the accelerator while removing the instrument pad assembly that I discovered mine. Finger went right through the rust. The pedal was loose from the plate, if not from a few mm of metal still hanging in there.

This rust can not be fixed or patched with it remaining in the car.

I had to treat the firewall for surface rust (due to the rust from the pedal plate) and do some respraying in that area.

I suspect that it was a few things coming together with this.
1. Leaking heater hoses (replaced with updated part number).
2. Insulation panels leaching the seeping coolant through onto the pedal plate.
3. Poor welds on studs and brackets welded to the pedal plate. Welds go through the metal and create weak spots prone to the rust.

The panel is sealed with an unusual expanded foam rather than a sealant.
This comes applied to the panel when new.

If that foam was available in a tube or applicator, then I’d suggest having that plate electroplated before installing.

Maybe someone could cad design a 3D printed plastic replacement?

I chose not to reinstall firewall insulation behind the brake booster and over the pedal plate. Instead I made a foam sound insulation panel for the inside of the car. To go behind the factory one that hides most of this rust.

In hindsight, I would have made another to go the whole way along the firewall inside behind the factory sound insulation as well.

 

[Fu Manchu]

The assembly of the HVAC and the brake booster etc can be seen at 6:50 in this:

 

[Fu Manchu]

Fu.
It's a damned shame that plate is so complicated to remove, seeing that it's actually a separate removable component. I suppose the consolation is that it IS removable rather than part of the firewall or floor pressings. From your description of the work involved, you would have to weigh up whether to have the car repaired or junk it if it was close in value to the cost of repair by a workshop. . Tough call if its otherwise a good car or a top spec one.

When I found it, my heart sank. We need this car and can't afford to replace it. My neighbour is a panel beater and was going to see if their shop could do the repair if I prepped it for them. Then I found that it is a panel that is bolted to the firewall and things looked up a bit more. I didn't sleep so well for a few nights. Was hard to tell my wife thats for sure.