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This thing just really makes a mess of the engine bay in that area. There aren't any actual leak leaks, but for reasons unknown there's just this haze of power steering fluid on the reservoir itself and the paintwork below it, as well as the hose fittings. I know it has a breather cap, is that what causes this?
I am pretty sure it’s the o-rings inside of the cap (caps if you have ACE). Try buying a new PS reservoir cap or replacing the o-ring. (hard to source the proper size and no idea what that size is btw, I tried)
I had an interesting observation last year -- I have a low (40K) miles D2. With ACE & PS combined reservoir. The reservoir was always covered in that same mist you mention, like every other D2 I’ve owned. I’d clean it to match the rest of the clean engine compartment, but even after a few hundred miles, the mist was back.
So I replaced it with a brand NOS ACE/PS reservoir which came with 2 new caps. Somehow in my repair, the 2 new caps didn’t make it to the new reservoir. They were in the top drawer of my tool chest so when I installed the new one, I re-used the old caps which looked fine to me. After awhile, the mist was back.
I then found those 2 new caps in my drawer at some point late last year-- and swapped them back. Mist has not returned.
I am pretty sure it’s the o-rings inside of the cap (caps if you have ACE). Try buying a new PS reservoir cap or replacing the o-ring. (hard to source the proper size and no idea what that size is btw, I tried)
I had an interesting observation last year -- I have a low (40K) miles D2. With ACE & PS combined reservoir. The reservoir was always covered in that same mist you mention, like every other D2 I’ve owned. I’d clean it to match the rest of the clean engine compartment, but even after a few hundred miles, the mist was back.
So I replaced it with a brand NOS ACE/PS reservoir which came with 2 new caps. Somehow in my repair, the 2 new caps didn’t make it to the new reservoir. They were in the top drawer of my tool chest so when I installed the new one, I re-used the old caps which looked fine to me. After awhile, the mist was back.
I then found those 2 new caps in my drawer at some point late last year-- and swapped them back. Mist has not returned.
In other words, I am pretty sure it’s the caps.
Thanks! Bummer the o-ring isn't available separately since the rest of the cap is just fine. I've been really weighting the Allisport aluminum one too. It's $500 USD shipped. Which is obviously a lot, but I've also had one PS reservoir split and leak and ofc they aren't available new anymore.
Last edited by Brandon318; Jan 28, 2026 at 09:11 AM.
Welp, I ended up stumbling upon this post by @Discorama and sure enough, went to Ace, they had it, bought six because why not at .59/per. The dimensions are the exact same as the original one, any minute difference can be chocked up to compression and age, and just the general slop inherent in measuring squishy rubber. Swapped, installed, and what a solid feeling seal it made, just the most assuring amount of resistance. Hopefully this keeps things cleaner.
The power steering reservoir is a mess
