New 928S Owner

[billyxking]

Hey everyone,

I just bought a 1986 928S two days ago. It's got 105k miles on it and it needs a little TLC, but not that much. The past two days I've been looking over the car with a fine tooth comb.

I noticed two things that seemed puzzling to me. On the passenger side near the excess coolant resevoir underneath the plastic air intake there is what I believe is the fuel pressure damper (based on the vacuum line diagram on the bottom of the hood).

What is confusing me is that is seems one of the main hook ups is disconnected. I don't know what this means!

I've attached some pictures, hopefully you can help me out. Where does this go? What effects are there if this isn't hooked up?!




And then, there seems to be an unhooked vacuum line just below the air filter. This picture shows the issue below:



Any insights? Suggestions? The car seems to be running fine. What does the fuel pressure damper do? What is that nipple under the air filter for and why isn't it hooked up?

Thanks to all that respond in advance

[dcrasta]

That nipple I believe is for the Air pump inlet or for one of the Crankcase vents. On the down side it allows unfiltered air to bypass your filter. Check the air pump lines you may be missing the inlet line for the air pump.

The small vacuum line to the Fuel pressure regulator is a vacuum reference. By allowing a vacuum signal to the regulator, it allows the fuel pressure to be lowered during high vacuum/low load conditions/ (such as coasting, or at idle.) When you are cruising, there is a slight vacuum that for fuel economy you can go slightly lean.

Some important things to know about your car.

If the last 4 digits of your VIN are > 0999 you have a coveted S3. This is the 32V (first Generation) with the 'Pipe Organ' intake, but with the Larger suspension and brakes from the S4.
As a S3 you can get a chip upgrade for your car from Portland Ken. (also know as Porken).

Is your odometer working? Are you sure of your mileage?
You will need to confirm the age and mileage on the Timing belt (better safe than sorry). I replaced my timing belt with a Gates belt and an automatic tensioner. You may need to investigate this if it is the option you would like to pursue.
A top end refresh will be in order. This should be addressed as soon as fiscally possible, along with new Fuel lines and vacuum lines.
Motormounts (and transmission mounts) may need to be checked as they collapse and can have a negative effect on the driver experience.

Other than that we need more pictures!

Welcome to the S3 club!

[gjmascoli]

If I may be so rude, what did you pay for your new baby?

[billyxking]

Thanks for all the great information. Where is the air pump, and what length and diameter hoses should I purchase? Right now I'm having difficulty locating specific things under the hood.

I paid $7500 USD for it. The seller told me that he had changed the timing belt within the past 1000 miles. IT's got fat new brake pads and new tires. He had it in his "personal collection" and said it spent some time in storage, but was started/moved around regularly. This worried me so we looked over a lot of the hoses for dry rot etc and didn't see anything telling. The odometer does work fine. Under the hood it says 32V but the VIN number is less than 0999, so I don't believe it's the S3. The fuel lines look new. What do the original fuel lines look like? If they are original I'll replace them, the ones on there now are bluish (see the bottom middle of the second picture I posted).

Thanks a ton guys. Anything else?

I will post more pictures tonight.

[MPDano]

Fuel lines do look good. Take more pics of the front of the engine and we can tell you if it's there or not. Also post up more pics of the car (interior/exterior). That first pic is the Diverter Valve, most are bad since the diaphragm inside goes bad. A quick test it to pull vacuum on the small nipple. Also, it will Divert air to the port to air cleaner box, hence your missing hose.

Welcome to the board!

[dcrasta]

There is a fuel line loop behind the engine, over the bellhousing and behind the air cleaner (airbox). This line has been know to rupture dumping fuel at 35 PSI on hot engine parts.

There is another line (return line I think) that goes over the passenger side of the motor. This also is a problem area.

Thirdly, there is the line that goes across the cylinder banks in the front. This is one of the more visible lines and is very short.

I would check all 3 lines. There have been instances of the lines 'looking' fine, however once removed and bent micro-cracks would be present.

If you cannot confirm the age of the timing belt (receipt for the work or parts would be best) and the age of the fuel lines (armor all sure makes things shiney and new looking!) I would put them on the short replacement list.

Other things to check would be to service all of the engine grounds, and I would remove and de-oxit all of the relays and fuses. Even if things are all working a good battery/ground service is cheap and wont hurt.

Good luck!

[MPDano]

Originally Posted by dcrasta

I would check all 3 lines. There have been instances of the lines 'looking' fine, however once removed and bent micro-cracks would be present.

dr, look at the hose in the pic. That is not stock and looks to be replaced recently, heck it even looks like it still has the hose powder all over it. As we can only see one, take more pics as requested and for sure check all fuel lines under the hood. Your also gonna have the small short ones going to the Injectors as well, then there are two short lines that connect to the Fuel Regulators/Dampers (can't remember what the correct name is).

[billyxking]

Originally Posted by MPDano

Fuel lines do look good. Take more pics of the front of the engine and we can tell you if it's there or not. Also post up more pics of the car (interior/exterior). That first pic is the Diverter Valve, most are bad since the diaphragm inside goes bad. A quick test it to pull vacuum on the small nipple. Also, it will Divert air to the port to air cleaner box, hence your missing hose.

Welcome to the board!

What kind of pressure will it be pushing? Looks like the two sizes of the air cleaner box and the diverter valve are different. Do I just turn the car on and in idle test the air flow in or out of it?

[billyxking]

I will certainly post more pics after work today. As for the pics, I will post interior/exterior and engine compartment. Any specific angles, shots I should take?

[Danglerb]

Welcome to the forum and 928 ownership.

What part of CA? There are active groups up and down the state, you may be close to one.

Its a really good idea to have a PPI, pre purchase inspection, but still a good idea post purchase to have someone expert in the 928 give it a careful look over and make a baseline on needed repairs, immediate and sooner or later.

Different people have different views of privacy, but for the best support post the vin and google with it to see if you find any previous discussions about your car specifically. If the previous owner, PO, was in the 928 community who it was could also help. Same for the shop it was serviced in.

Sharp image, in focus etc is more important than angles, but I would say for now just some shots to show off your new car.

[billyxking]

Originally Posted by Danglerb

Welcome to the forum and 928 ownership.

What part of CA? There are active groups up and down the state, you may be close to one.

Its a really good idea to have a PPI, pre purchase inspection, but still a good idea post purchase to have someone expert in the 928 give it a careful look over and make a baseline on needed repairs, immediate and sooner or later.

Different people have different views of privacy, but for the best support post the vin and google with it to see if you find any previous discussions about your car specifically. If the previous owner, PO, was in the 928 community who it was could also help. Same for the shop it was serviced in.

Sharp image, in focus etc is more important than angles, but I would say for now just some shots to show off your new car.

I'm in Hermosa Beach. I would love to have a 928 expert come and look the car over. I'm building up a worklist for the car but mostly it's electrical stuff (side mirror motor for example). The previous owner of the car lived in Orange county and said he had a porsche mechanic in fullerton do the work on this car. I figure I'd find one out here and do what I can myself. I'm still waiting on him to email me the service records of the car.

[Danglerb]

Originally Posted by billyxking

I'm in Hermosa Beach. I would love to have a 928 expert come and look the car over. I'm building up a worklist for the car but mostly it's electrical stuff (side mirror motor for example). The previous owner of the car lived in Orange county and said he had a porsche mechanic in fullerton do the work on this car. I figure I'd find one out here and do what I can myself. I'm still waiting on him to email me the service records of the car.

Ah lucky you, sounds like the mechanic is Greg Brown at Precision Motorwerks, and he is as good as it gets with a 928. Once you have the paperwork, look over whats been done and when, then do a inspection of the easy stuff, lights, all the controls, etc. then check with Greg on a service schedule. Sorry I don't know of anybody good closer to you, but there used to be quite a few active guys in your area, but they don't post very often.

BTW a Porsche shop won't do, you need someone expert in the 928 with a few in the shop all the time.

[stepson]

Originally Posted by Danglerb

Ah lucky you, sounds like the mechanic is Greg Brown at Precision Motorwerks, and he is as good as it gets with a 928. Once you have the paperwork, look over whats been done and when, then do a inspection of the easy stuff, lights, all the controls, etc. then check with Greg on a service schedule. Sorry I don't know of anybody good closer to you, but there used to be quite a few active guys in your area, but they don't post very often.

BTW a Porsche shop won't do, you need someone expert in the 928 with a few in the shop all the time.

The work done on this car does not look like Greg Brown work. Greg would not leave vacuum lines unattached.

+1 on using a 928 mechanic versus a Porsche mechanic.

[billyxking]

Originally Posted by stepson

The work done on this car does not look like Greg Brown work. Greg would not leave vacuum lines unattached.

+1 on using a 928 mechanic versus a Porsche mechanic.

What length and diameter vacuum line should I get for that? Also what test should I run to verify if the diverter valve is working or not?

[Danglerb]

Don't worry about it for now unless it hasn't passed smog. That hose just vents the air pump to the air filter box.

Its a short L molded hose, $33 92811315902 Pelican has them, but be sure you have the fitting on the bottom of the air filter box it goes to.

Correct Greg doesn't leave off vacuum hoses, but some of his customers do some of their own work.

[billyxking]

Originally Posted by Danglerb

Don't worry about it for now unless it hasn't passed smog. That hose just vents the air pump to the air filter box.

Its a short L molded hose, $33 92811315902 Pelican has them, but be sure you have the fitting on the bottom of the air filter box it goes to.

Correct Greg doesn't leave off vacuum hoses, but some of his customers do some of their own work.

Thanks for finding the part but, I have no idea what the fitting is?

[billyxking]

Originally Posted by Danglerb

Don't worry about it for now unless it hasn't passed smog. That hose just vents the air pump to the air filter box.

Its a short L molded hose, $33 92811315902 Pelican has them, but be sure you have the fitting on the bottom of the air filter box it goes to.

Correct Greg doesn't leave off vacuum hoses, but some of his customers do some of their own work.

Also which one is the one that fits my car?

928 (1983-1986)
or
928 (1983-1986) (M28.43/44)

[Danglerb]

DC Auto has a diagram out of the Porsche catalog, but physically verify what you have on the air filter box.
Porsche 928 Porsche Parts And Accessories Parts

[Pete R]

Originally Posted by MPDano

Fuel lines do look good.

Don't go by that though. If you don't know how old they are chance them. This line off my 951 looked 100% good. I never would have changed it, but someone told me I should. When I turned it over and stretched it out......

[billyxking]

Hey everyone I took some pictures and I have some updates.

First off I noticed that the car doesn't have a catalytic converter. Seems necessary to have one doesn't it? Will I pass smog? I need that to register the car being in CA and everything.