My new to me 90 S4 still hasn't made it to the house, still working on making space in the garage but hope to have it here soon. In the meantime I've been hanging out at the ex mother-in-law's where it currently is, tinkering a little. I thought about buying a battery and seeing if it'll start but I'm also finding little things here and there that make me wonder if I should tow it here and start tearing it apart. Looking for wisdom and guidance. I downloaded the manuals but for some reason the wiring diagrams didn't come with so I need to figure that out. My biggest questions right now is some wiring and connections I found in the engine bay, I'm attaching pictures of some of the questionable things. Any thoughts and guidance would be greatly appreciated and if anybody is in Wyoming or near

The connections in the middle of the pic, what are they for? The ones on the other side of the engin bay are in worse shape and in a pic below


When I touch these connectors they start to crumble

There is a silver braided line at the bottom of the pic, is that correct?

If you zoom in you can see a couple questionable things

I'm excited to one day drive it, I had a poster of one on the wall as a kid in the late 80s
with a 928 that would be willing to meet up and let me check theirs out that would be awesome. This is the first time I've ever been around one up close.

 

Sorry this is a bit broken up, is it too long? The end of my message is after my attachments. Also noticed the first pic isn't what I was talking about but is one of my concerns. Thanks for reading and any advice or comments!!

 

The picture with the bigger brown wires I can see electrical tape so I know someone has been in there.

 

Photo 1. That knock sensor, I think. The plastic part on the sensor side always falls apart like that. You can replace the sensor or just the connector. I'm cheap and lazy, I would replace just the connector. I have a few sources. I think Roger has it. There are two knock sensors, and the cam position sensor which are three pin connectors like that and they all fall apart.
Photo 2: Those are the main wires from the battery. They are meant to be red, but have decayed. Disconnect the battery and go over all exposed wires in this area. Look under the tape. It can be fire hazard when the wire jackets fall off, which they like to do. I use heat shrink, but you can replace the engine side harness it you want for medium money. $1000 ish, I think. I repaired mine. There are two covers missing. One for the jump post, and one for the whole area.
Photo 3: Not 100% sure if those are for the ABS or the break pad sensor wires. Both of these harnesses have plastic housings that just crumble. I don't think there are replacement housings. I deal with this by crimping in bullit plugs and sockets on the break pad sensors and just removed my whole ABS system wiring harness. I'm sure there is a better solution, but I don't like ABS so this is fine for me.

 

my opinion: if you don't know the maintenance history for sure, and haven't heard the car run, tow it home and dig in. Fuel lines, hoses, all those electrical problems you've already found plus the ones you don't know about yet - fix them before they cause you trouble. You can put on a new timing belt, check the water pump, swap all the fluids.. You'll have a spring project and then can enjoy the WY summer driving!

 

Your photos suggest this example needs some loving care and attention and is typical of so many that have what we refer to as "deferred maintenance"- in other words things that should have been done but have not been attended to.

Karl has pretty much hit the nail on the head with his preliminary analysis and if you have no historical records you just have to start from scratch and go through the basics until you have something to work with and can run with a minimum of worry. I would think you need to budget a minimum of US$10k for basic parts just to get it running reasonably safely and same again for labour if you have to get someone to do the work for you.

As a minimum your future has a definite inlet manifold removal on the cards with replacement of the various gubbins that sit underneath it. It will need a thrust bearing check and assuming nothing found to be wrong some mitigation to prevent TBF from possibly occurring. You will need a new timing belt and probably the accessories that go with the tensioning system before running the engine. You need to remove and most likely replace the front of engine wiring harness- it is showing clear signs of "cable cancer" as I call it. You will likely need to replace the power steering hoses and especially the high pressure hose and same for all the fuel system hoses in the car. The LH computer will likely need a revamp [if it has not been done previously] and the MAF will need checking for flow accuracy and a new hot wire revamp. The fuel injectors will likely need cleaning and the in-tank fuel pump checking out replacing the in-tank hose whilst at it. You will need to take measures to ensure the fuel tank insert does not spin whilst trying to remove the in-tank pump. You may well need a new fuel pressure regulator and two dampers. Usual service items like brake pads, disc wear, suspension units and bushings etc will need to be checked out. The PSD system will need to be checked out and flushed with focus on the slave cylinder. The tyres will likely [but not necessarily] need replacement. The other major "elephant in the room" will be the head gaskets. Suggest you research the above mentioned topics but use the Google search engine [rather than the forum search feature] and when typing in the topic add Rennlist 928 to the search criteria.

Seems to me you have a platform for a real nice example if you attend to the above mentioned items in appropriate detail and the basics are sound- once you have then your focus can shift to the cosmetics and whatever needs to be done in that regard. You may have acquired a dream car for a rock bottom price but you do not get cheap maintenance thrown in with it- just be realistic with your expectations and you will hopefully find it a rewarding experience.

 

Thanks for the responses! Pretty much what I figured. I have gone through most of what is recommended to read first on this forum, several times and I read through many post gathering intel. The positive is I like working on cars, always have. I'm not in a hurry to get it on the road and knew when the decision was made to purchase that it would more than likely be years before I was driving it regularly. I do plan to drive it often! I would prefer to have peace of mind knowing I have gone through and changed out the aged items, repaired and replaced previous patches made by someone else, insured that I can drive the car (hopefully) 1000 miles on a road trip and not have to worry (as much) that I may be calling a tow truck to some unknown shop.

Thanks again for the comments so far, I'll continue to be on this forum and will update with pics when things happen!