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grepin 09-21-2018 03:19 AM

I am in trouble.
Dont know what i was thinking but I bought a 928 unseen and apparently it only needed a fuel pump which was provided.
The car has been sitting around for many years so i expected to clean the fuel tank do the timing belt, plugs water pump and all the standard bits that i have been reading about.
Anyway I lift the bonnet and there is a plug just hanging loose on its lead with the hole in the head exposed.
Also there is a puddle of white liquid in the V and a fair bit of oil inside the intake plenum. V liquid looks like more water than oil Is there any water lines there that could have leaked.
I did think the head gasket however the engine oil is very clean on the dipstick yet to drain.
Anyway I was intending to pull all that down but my main issue is the plug not installed.
The car was a runner and not seized before it stopped. But the owner bought as is and now I have the problems.
I am thinking the head needs to come off however if I stick a borescope into that cyclinder and all looks good or even give it a ltittle vacuum can I hope that all might be well.

Besides all the other reasons that I have read many threads about that would mean a 928 wont run.

1984 928S Auto

FredR 09-21-2018 03:57 AM

Lesson No1: tell us what model/year you are talking about and whether it is a manual or auto tranny.
Lesson No2 - post some pictures- there are a zillion plugs on these cars

grepin 09-21-2018 04:01 AM

By the way as I dive into the manuals can anyone pinpoint what this hose pipe is for or goes to. RHD.

grepin 09-21-2018 04:07 AM

Yes sorry.
1984 928S Auto RHD.
The plug was one of the spark plugs.
Just hanging in the breeze attached to the lead and head open.
I am still thinking boreascope and see whats going on in there then if bad head off if good then move on replacing everything and eventually see if it starts.
If its head off it will be a long time waiting.

gazfish 09-21-2018 04:28 AM

When you put the air filter box back in place (assuming you have one) it sits into that hose. It's part of the basic emissions control system.

FredR 09-21-2018 04:48 AM


Folks on this list like to see owners brave enough [dumb enough?] to take on these basket cases and bring them back to full running order and better. No car likes to be left like this for long periods of time and the 928 is no exception and then some.

If the engine was left with a spark plug missing that of course will do not good whatsoever. A boroscope inspection would be a good start. If the car was sat in a location prone to high levels of humidity then obviously more to fear. The 928 motor has a number of points where coolant can leak into the Vee, most notably the water bridge at the front of the engine and there are a couple of coolant nipples that can and do fail [there is a thread covering one such item a few days ago].

The open hose on your photo mates into the bottom of the airbox if that is what you refer- part of the pollution control kit of the day.

If you do not know how long the motor has been sat and have no idea of the history then pulling the motor and the heads is no bad things as head gaskets can suffer long term issues and corrosion at the top of the cylinders on the water jacket side is sadly quite common. If you have the capability, pulling the motor and resealing it top to bottom is a good bet long term. This gives you the opportunity to determine more definitively whether the motor has deeper issues. As I recall your motor will have studs fastening the cylinder heads and if correct it means the engine has to be pulled to remove the heads. Many consider this a good thing.

grepin 09-21-2018 06:25 AM

Thats some good news i have a feeling something has seeped in there.
I looked under the air cleaner cover...obviously not hard enough. Unless it was upside down.
The previous owner said he pulled the lead to check for spark but forgot to put it back.
I am assured it does turn over as he has done it. Might be a good or bad thing but i am going to check the cam positions as a first analysis step.
I have been reading about these cars for months and haven't scratched the surface.
I had a game plan for when it arrived that is now on its head. But I will learn heaps and enjoy the challenge.
I just wanted to drive it first before all the big tasks had to happen.
But it was cheap and a conscious decision to go through everything.
My 7 year old has agreed to help otherwise he cant drive it when he is sixteen.
Hope it is running by then.

Ad0911 09-21-2018 07:41 AM

It seems like there is one of these adventures each week. Is the 928 gaining interest?

DeWolf 09-21-2018 08:23 AM


I'm in Adelaide as well and can help out whenever needed. I have lots of tools and a fair bit of experience with 928's now.


bureau13 09-21-2018 10:21 AM

It can be very rewarding to bring these beasts back from near-death. It can also be frustrating in the midst of a job when nothing seems to work as it should. More pictures up some more pictures!

Not sure what to say about someone who pulls a plug to check for spark and the just...leaves it out? I've done some pretty dumb stuff too but...damn...

Ducman82 09-21-2018 11:30 AM

Did he take he plug out??

SteveG 09-21-2018 12:05 PM

with the hole in the head exposed
I believe you said you had a hole in your head. That is a prerequisite around here. :)

Welcome to the shark tank.

docmirror 09-21-2018 12:35 PM

1984 is likely not an interference engine. However, it might be, so be careful. with what info we have, here's how I'd go at this one.

1. Buy an aerosol can of "carb/fuel inj cleaner" and a can of WD-40 or AU equivalent. Spritz a bit of lube in that open plug hole. Leave the plug out.
2. Take off the intake tubes, and look down the holes to check the cond of the timing belt. Or, take off one side of the cam gear upper cover, and have a good look at the belt and path.
3. Provided the belt and cam gears look ok, try to rotate the engine by using the big bolt and breaker bar on the nose of the crank. Clockwise, as standing in front of the front bumper please. Stop if there is hard resistance, not like compression.
4. If the engine rolls around without any mechanical interference for two revolutions, take the breaker bar off, and crank the engine briefly to clear any schmootz that got into that open cyl.
5. Another small spritz of WD-40(or equiv) into that plug hole and put the plug back in, and the ign wire on the plug.
6. With the air cleaner removed, and while a helper(or son) cranks the engine from the driver seat, spritz the 'carb/fuel inj cleaner' from the aerosol can into the MAF. It may fire up briefly.
7. Stop here for a while an do all the catch-up stuff like fresh oil, filter, coolant, fresh fuel.
8. Remove the fuel pump relay, and jumper the fuel pump pins 30 to 87. go to the rear bottom and listen carefully for the fuel pump buzzing. If it buzzes, go to the engine bay and carefully look for fuel leaks. (all hoses will be replaced sooner rather than later)
9. If no fuel leaks, try to start the car. If it starts, check your oil pressure for 4-5 bar.

This is just to get your mind at ease, still a lot of work ahead, but this is a primer for what comes later.

karl ruiter 09-21-2018 08:10 PM

Doc is always right, but personally I would pull all the remaining plugs to do that test. That way there should be little resistance and you wont have to wonder what is compression and what is something else. Assuming the plugs are reasonably willing to come out.

grepin 09-21-2018 09:02 PM

Hi everyone thanks a lot.
My decision has been made to start pulling the intake side down top end remove and replace all spark plugs and at the same time have a look at all the cylinders.
Pull the injectors and any fuel related devices and have them checked.
Replace all fuel lines gaskets and water bridge related bits and pieces.
Then the top will be done.
Pull the covers off the cams to the point I can check tension and that the cams gears align.
Look for leaks and worn gears etc. Check tension-er (might go Porken later)
Clean the fuel tank its been empty for a long time and replace fuel pump and filter. Remove in tank pump and replace with mesh filter. Car came with a new fuel pump in the boot.
Not going to do the cam belt or water pump at this stage if I dont have to just trying to get to starting phase. To be done later once i know I have a runner.
This is where you may need to throw some technical help my way DeWolf when I suspect she wont fire for some other electrical reason. Appreciate the offer.
With that thought I have a new fuel relay and all fuses to be replaced in the CE panel.
So I am chasing what I need to have checked or just replace related to the top end side CPS, coolant temp sender unit and other stuff that is hard to fault find later or can ruin your day when the key is turned.
Basically a shopping list.
Searching on here so no need to answer unless you feel like it.
But it will be slow going need to be smart with the cash flow.
I will post pics and keep people informed.

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