The sunroof glass on my 88 GT never pulled tight to the weatherstrip on the latch side, this caused a pretty good water leak every time I washed it. Even after replacing the weatherstrip with a factory NOS part the problem persisted. So I took the latch apart to see if there was a way to adjust it to close the glass tighter to the weatherstrip. I found that there is a 2mm thick plastic spacer between the latch and the roof. I figured a thicker spacer would be needed to remedy my issue. I measured the spacer and modeled it in Fusion 360 and 3D printed a new one that was 3mm thick. After installing it I still had a slight leak so I printed another one at 4mm thick which solved my leak problem.

I have uploaded the .stl files to Thingiverse for both 3mm and 4mm thick spacers if you would like to make one for yourself. https://www.thingiverse.com/thing:4655000

Great thinking certainly add more pressure to seal.

I have the exact same problem - and a 3D printer to boot. 😁

So how do you remove the latch? (I could just go out to my car and check for myself but it's storming outside)

There is a single screw holding a plastic cover in place. Disconnect the sunroof from the latch and remove the cover. There are 2 10mm nuts that hold the latch to the ceiling. Remove them and the latch comes right off.

"I Need Spacers..." But OE Spacer likely Isn't your problem(s) w/ loose latch, leaks, etc.

Bent latch parts, Bent Roof where the two bolt heads attach for the latch, bend front "ears," holes on roof or both are damage, and more can cause leaks, air noise, or both.

Example: 2 latch bolts aren't studs welded to the roof. Their loose "carriage bolts" w/ very small heads put into "keyhole" openings and the keyhole bents when anything hits glass while open, latch too tight, and likely other reasons. So installing a "spacers fix" w/o fixing the keyholes is only to bend them more and may tear out the bolt heads doing more damage.

Adding more or changing Spacers only last short term to many because don't fit the real problem(s).
Many people replacing roof seal often have same problems and old seal wasn't bad. Most replacement seals are thicker and puts more strain on damage weak parts.

Use search to find older threads on this.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

quote Originally posted by seajai: The sunroof glass on my 88 GT never pulled tight to the weatherstrip on the latch side, this caused a pretty good water leak every time I washed it. Even after replacing the weatherstrip with a factory NOS part the problem persisted.

You should be able to drive your Fiero with the sunroof open without water entering the cabin.

I posted this in a recent thread...

quote Originally posted by Patrick Here: Before you go through the trouble of replacing the sunroof weatherstripping, try two things first. 1) Remove the sunroof panel from the car, and make sure the drain holes in each corner of the sunroof opening are not plugged. 2) While the sunroof panel is out... clean the rubber weatherstrip, and then apply castor oil to revitalize and slightly swell it. You may now find you don't need to replace the sunroof weatherstripping.

[This message has been edited by Patrick (edited 11-16-2020).]

Ogre, nothing was bent, nothing was loose, and the bolts weren't pulled out. I checked all that stuff beforehand. The sunroof glass simply wasn't tight against the seal. Adding the thicker spacer fixed that and it's been a year since I did this and nothing had broken so I'd say it was a good fix.

Patrick, I didn't have a leak when driving in the rain, I had a leak when I washed my car. The poor contact allowed the water to run in between the glass and weatherstrip when rinsing off the soap. I've driven in the rain many times with the sunroof open and it didn't leak, even in very heavy rain. The drains are clear and the seal was brand new so those were not my problem.

I spent a lot of years as a tech at a dealership and most of my adult life working on cars and I'm not stupid. If I can figure out how to install a Chrysler engine in a Fiero I'm pretty sure I can properly diagnose a leaky sunroof.

quote Originally posted by seajai: I spent a lot of years as a tech at a dealership and most of my adult life working on cars and I'm not stupid. If I can figure out how to install a Chrysler engine in a Fiero I'm pretty sure I can properly diagnose a leaky sunroof.

Seajai, I certainly wasn't questioning your or anybody else's intelligence. My post was simply to inform anyone reading this thread that there are at least a couple of other avenues to explore in regards to a leaky sunroof.

For my first Fiero 25 years ago, I recall making a shim as you have done, but cut from sheet metal. On three subsequent Fieros with sunroofs, I haven't had to go that route.