RJD2614

Hey folks, well, after a bit of a crash course in 928 top engine work, it appears I'm just about ready to fire my '85 auto 928S for the first time in 6(?) months. I look back on seeing these cars at events, and thinking "my god that engine bay is a rats nest with spaghetti on top". And while I am just scratching the surface of getting my head around these cars, it does feel good to have come this far. As of this morning, I have:

-fuel tank/system pulled, cleaned and rebuilt with new everything
-new PS hoses
-top end refresh complete and re-assembled
-fuel pressure tested, no leaks and holds pressure
-car holds oil and PS fluid
-new spark plug wires

the last few things I need to do are to get coolant in(the cap at the overflow tank is fighting me tooth and nail to come off, I never removed it when I acquired the car earlier this year), test vacuum, and figure out where this one wire goes. the wire in question is part of the brown harness/loom that travels across the front of the engine, at the PS. two wires split off at the front PS timing belt cover, with one terminating at a (sensor in the PS camshaft?); the other one came loose in disassembly and it doesnt have a blade or fitting attached to it. I don't think it ever did. Any ideas as to where this should connect to? and am I overlooking anything else? thanks for the second set of eyes on my work! (oh, I should mention, I don't have the blue breather hose and one of the vent hoses for the evap tank connected just yet, I am dropping the car next week for a timing belt/WP job and was going to have them get that sorted....am planning on a smog pump delete)

Speedtoys

AC clutch?

Zirconocene

Just one picky comment, I guess, but it's because your intake looks so nice: you have an overly long hose clamp on the driver's side and the extra length looks like it's ready to start scratching up your intake as the engine starts to move. It's hard to really tell how close it is, so maybe there's no real issue, it would just be a shame to have something happen to that nice work.

ETA: I don't know the S3 very well, but is the throttle cable routed correctly? It seems like it should run under the strut brace.

Looks good!

RJD2614

good catch! thanks. i started running out of new hose clamps in the exact sizes. i'll snip that guy off(I am currently using some length of fuel hose I had lying around the shop for vacuum to the brake booster, I should probably find the proper vacuum hose length...)

Petza914

The brake booster hose is a special reinforced hose type so that it doesn't collapse under vacuum. You need to order the correct hose # type for that and not just use regular vacuum hose. In the meantime, you can go to your local ace hardware store to their springs assortment and find a loosely cooked spring with a diameter that just fits inside the rubber hose you're using and the spring will make it impossible for vacuum to collapse the hose.

RJD2614

Gotcha-thanks @Petza914 I appreciate that. I'll get on it.

So I attempted to fire the car this morning, mostly to see what the fuel pressure did. It just stumbled and attempted to run, never took an idle at all. Fuel pressure runs up to about 75PSI, and then slowly scales back to around 35-40PSI once I let it rest. Does that sound normal/ideal for fuel pressure? I am going to try to disconnect the MAF and see if it takes an idle, I believe that's how I got it to run when I acquired the car.

Kevin in Atlanta

75 psi sounds way too high. 55 psi engine off fuel pump relay jumps and 48 psi running with good vacuum for an S3.

Bad fuel pressure regulator and or wrong fuel pump?

RJD2614

Thanks Kevin. Almost all the parts were purchased from 928srus, and literally everything other than the tank and the hard lines is new, so it seems highly unlikely that the wrong fuel pump was sent by Roger. My current plan is to use a vacuum pump directly on the FPR and see how the fuel pressure looks. If 78PSI is too high with the relay jumpered/engine not running, it sounds like the FPR is the only culprit left. I'll report back once I get a chance to take some readings.

sendarius

Shouldn't that large brown cable on the passenger side (left of photo) go UNDER the PS upper cam cover?

At least that's what Dwayne's write-up told me.

Edited to add: The cable you are holding certainly does look like the one for the AC clutch. I thought the other end appears at lower left in the photo, but maybe not now that I realise the change in orientation.