Zaytar

Hi guys,

First time UK poster here. Hope you may be able to advise.

I've searched the forum regarding my issue, and there are numerous posts regarding boot (trunk) latch issues, but I cannot find anything which exactly describes my problem.

I have a 2008 D3 S8. The boot lid motor seems absolutely fine i.e. not unusually slow, noisy or weak. Also I have no boot closure issues at all. However occasionally when I open the boot lid using the remote or internal door button, the boot attempts to lift and then immediately shuts again - Importantly the latch does not seem to have released. When I open the boot by hand and this latch jam occurs, a short nudge by hand helps to release the latch and the boot raises fine. As I said this is an occasional issue, which randomly occurs regardless of weather conditions etc. The boot closes absolutely fine every time. Something with the latch mechanism just does not seem to release on opening and requires a small shove - I've tried lubricating but to no avail.

Has anyone experienced this exact issue and can offer any advice?

Many thanks.

CobraCommander

Welcome and this sounds familiar to the week boot motor that we all have experienced and or fixed. You may want to lubricate the hinge/lock mechanism to see if that helps with the issue, but I'd bet its the motor.

MP4.2+6.0

Generally agreed, though by 2008 it probably has the "last" new and improved trunk motor; there are at least three generations of them. For OP, look back there for the motor. On a left hand drive one like mine, it is above the battery on the passenger side. If the motor case is largely aluminum/metal, that's the final one. If a lot of plastic, maybe with a visible number handwritten in large grease pencil, that's probably the next to last one. Early ones had no number written on them, but I don't think 2008's would have that early version.

As CobraCommander said, try lubricating all hinge points. You can also replace the little shock absorber lift assist tubes, which are much cheaper than the motor, especially if you find (quality) aftermarket or OES like Sachs. rockauto.co.uk has the Sachs ones for example.

dvs_dave

+2. This is classic symptoms of the lid motor weakening (the electromagnetic clutch inside it wears out). Nothing to do with the latch.

Even if it's a late model with the newest motor revision, they go the same way too. Someone on here bought the latest version and it only lasted a year or so for them. So all in all its a **** poor design.

mishar

+2 now +3 Dave was faster

Also check if your hinges (one on the actuator side, I believe right) are bent a bit so that plastic on it is touching shock absorber. They can be easily straitened with big players.

RobertV

Would hit the trunk release in door or remote....right side of trunk would lift just a bit....latch wouldn't release....the was a loud bang....trunk would close again.
Took several visit to the dealer before they performed a TSB. I don't know the exact details on the TSB, but now the trunk releases with much more force and noise. I'll try to dig up the paperwork on that one to get the TSB #. Might be worth a call to a friendly dealer or a conversation with the lead tech as it could be something you could perform if it is just a latch adjustment or latch replacement.

EDIT TSB# 2019840\3 adjuster bumper stops. Sorry I don't have my car in front of me to look at it, but I suspect there are adjustable rubber bumpers for the trunk lid.

Zaytar

Many thanks all. I'll get on it and follow through on all your tips. Will report back. Thanks again..

dvs_dave

Trust us on this....it's the lid motor on the way out. No adjusting of bump stops or whatever will fix it in the long term other than a new motor. And then it's still not 100% gauranteed

Zaytar

Thanks Dave. I agree with you, certainly looking that way. I'm still relatively new to S8 ownership, and was convinced it must be something to do with a defective latch. When I searched this and people referred to a defective motor I always assumed they were referring to the motor that actually lifts the lid - Slow realization there is a motor that controls the latch... doh!

mishar

Look at the lid and push trunk button on the remote. If you hear fairly loud click and the lid goes up for about half inch and than the right side rise a bit with slow wining sound just to drop back and lock with different short wining sound, it is your lid opening motor. It is just above the battery. Check if it is aluminum or plastic body.