OK, my hatch release runs but started binding instead of opening the hatch. When I go around to turn the key it opens with just a slight turn, like the release had nearly opened it. A second pulse would sometimes open it, and sometimes just run freely.

Both parts of the latch (male tongue and lower liner) look in excellent condition.

I have so far tried adjusting the vertical position of the motor. Move it up a little, and the release runs freely without opening. Move it down a little, and the release runs until a binding point without opening.

Is there something worn out here that would be solved by replacing the whole motor? The release cam?

 

I think the remote hatch release was designed by the same guy who decided to put the galvanized steel inserts in the washer tanks. I have abandoned the original motor and installed a VW release motor. Even with that upgrade, or perhaps because of it, I have found that there is a very narrow sweet spot for adjusting the mechanism so it pops the hatch. Also, as your avatar suggests, lubrication is your friend. Even though everything is nylon, a little silicone grease or white lithium grease helps.

A 100 percent hatch pop score is a lofty goal. I am satisfied with B grade on this. I have this idea that cutting down the spring under the plunger in the female end will help, but exploring this will have to wait until after I am retired.

I don't know how the hatch release made it out of pre-production testing.

 

They may look like they're in excellent condition... but the female portion is probably worn.

Have you tried the "zip-tie" trick?

 

Seems we have been hereabouts before:
https://rennlist.com/forums/928-foru...-sticking.html

Essentially the same advice:

https://rennlist.com/forums/928-foru...h-release.html

If that doesn't work the VW unit is a big improvement IMO. But you still need an unlatching cam that is capable of opening the hatch... you can test that manually with the motor out.

Alan

 

The "Zip-tie" trick worked perfectly for me for the past six years!
Tried many things before that without success.

Look at Alan's post (#14) here for a quick explanation.

https://rennlist.com/forums/928-foru...tch-motor.html

 

Check to see if the unlatching cam is at all concave. If so it can be replaced (I believe roger has them) Also check for hairline cracking on outer surface. If cracked then is no good and time to replace with earlier (more robust) unit.

 

OK, thanks to you guys plus the workshop manual, it is again fixed--temporarily no doubt. The trick was again adjusting vertically, greasing the latch and lower receptacle, and a shot of WD-40 on the shaft assembly. Latch opened 5 out of 5 attempts.

928 engineering feats include the engine, rear transaxle and Weissach axle. The hatch release goes into the engineering de-feats, along with the climate control, the sunroof/window switches and the folding side view mirrors.

-Sean

 

As predicted, my fix didn't last longer than a couple of days. I examined the situation again, discovered a hidden crack in the lower liner on the rearward side - always a problem because it allows the tongue to move too far toward the rear of the car. I will get a new liner eventually, but for the moment it is fixed with a piece of duct tape over the cracked part, in back of the white tongue. Opening good again, for now.