**MOST Common 928 Issues AND Fixes**
 

Post "Known" Common Issues and the Fixes. Pics are a Plus :D

Please try and stay with the same Format. Issue - Fix - Pic (if any)

Index:

1) 14 Pin Connector: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes.html

2) Grounds: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes.html

3) Headlights not going down: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes.html

4) Splash Guards (Homemade): http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes.html

5) Broken Wheel Locks: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes.html

6) CIS - Hesitation on throttle up: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes.html

7) AC non-op in hot weather: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes.html

8) Transmission slipping: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-2.html

9) Electrical short tip: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-2.html

10) Measuring Tranny Pressures: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-2.html

11) Sunroof non-op: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-2.html

12) Low Alternator Output: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-2.html

13) Dim Instrument Panel Lights: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-2.html

14) Brake Booster Vac Line Alternative: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-2.html

15) HVAC Controller Buzz: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-2.html

16) Clutch Fan Alternative: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-3.html

17) Fuel Lines Replacement: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-3.html

18) Removing Rear Bumper: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-3.html

19) Aluminum Ball joints: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-3.html

20) Front Seat Sagging: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-3.html

21) Famous Green Wire (no spark or weak spark): http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-3.html

22) Bass Speaker in Spare Tire: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-3.html

23) Engine Specs by year and location (US/Euro): http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-3.html

24) Front Shock Replacement: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-4.html

25) CV Joint Rebuild: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-4.html

26) S4 Wing Install on OB: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-4.html

27) Oil Temp Gauge install: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-4.html

28) Wideband O2 and Gauge install: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-4.html

29) AC Compressor R12 convert to R134: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-4.html

30) Odometer non-op (bad gear): http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-4.html

31) Passenger area clicking noise: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-5.html

32) Manual Ball Cup Replace: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-5.html

33) Leaky Fuel Tank Repair: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-5.html

34) Motor Mounts R&R: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-5.html

35) Battery Shut-Off Switch: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-5.html

36) How to remove Torque and Tranny: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-5.html

37) Tie Rods and Rack Bushing Replacement: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-5.html

38) Wheel Size and Offset HELP!: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-6.html#post7364487

39) Ignition Switch Replacement: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-6.html

40) Air Intake Tube Alternative: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-6.html

41) Subwoofer Foam Surround Rebuild: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-6.html

42) Stuck Brake Rotor: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-6.html

43) Hood Heat Shield Replacement: http://forums.pelicanparts.com/porsche-928-technical-forum/607208-most-common-928-issues-fixes-6.html

I'll Start this out:

Issue: 14 Pin Connector: Corrosion or broken wiring causing Various Electrical problems.

Fix: Always disconnect Battery when working with electrical. Use a small wire brush to clean the pins and the backs of the pins. this requires you to split the Halves. Be careful when splitting the halves as the pins may come out the Holder.

Pics: Here are some pics posted by Ender928. This is what you hope not to see when you split the halves. You'll need to repair wire here which will require some soldering. Also his Holder is cracked and needs to be replaced :( .

http://forums.pelicanparts.com/uploa...1301624274.jpg

http://forums.pelicanparts.com/uploa...1301624339.jpg

http://forums.pelicanparts.com/uploa...1301624390.jpg

before you find out the 14 pin is damaged inspect or clean or replace the ground strap at the battery.

HINT if you wash the car or its parked in the rain open the hatch and inspect the floor of the hatch,
if its wet then chances are very good the ground cable is corroded internal to the covering and should be replaced,
if there are funny elex issues haunting your ride

Ground Points: Corrosion causing bad ground contact

Normal Fix: Use a small wire brush to clean the ground area as well as the round terminals

Here is a Pic of an S4 Ground Points and hopefully we can surface one for earlier models, which at that time I can add here.

http://forums.pelicanparts.com/uploa...1304871590.jpg

Problem...
Rubber FUEL lines. They do not age well and are responsible for many fires where the car is a total loss.

FIX....
928Rus sells a fuel line replacement kit. Includes all hoses that need replacing with all necessary clamps as well.

This is one FIX that you need to do when you buy a car. Even when the hoses LOOK fine they are NOT. Rubber hoses do not last 25 plus years without degrading. Hose location and layout vary year to year so check with Roger...the set he sells has all hoses for all years so there will be some you don't need.

OK, for early body cars see below. Some variation between CIS and Ljet and LH Jet euros. Note the voice-over for some points not shown on these diagrams.


http://forums.pelicanparts.com/uploa...1304875014.jpg


http://forums.pelicanparts.com/uploa...1304875030.jpg



Point 9 (9a and 9b) There are two crucial ground attachments on the 16V passenger side cam cover. They ground the engine electronics & the injector harness.
One is at the top of the "O" in the word Porsche cast into the cam cover --- and it may be covered-up by the emissions air injection valve/hose. The second attachment point on the cam cover is more visible and is closer to front of car.

Point 10 For later Euro cars, look for ground wires attached to the back of cam gear metal rear covers. These are for the "final stage ignition amplifiers"

And now that there are so many brand X import hoses on the market,make sure to replace with NAME brands,and graded fuel injection hose, first replacement when you buy the car, then maximum every 5 years to next replace, these hoses take big pressure, and nothing is forever.
(a pinhole with 60 pounds of pressue behind it will SPRAY a lot of fuel REAL fast,-they don't just drip!)

Use 30 R9 fuel injection hose.

Do not use 30 R6.

Great details so far, not to meantioned the up-close pics :-)

'79 Headlights not going down
 

Just posting this in case someone is searching for solutions. My headlights work just fine and would go up, however, would not go down after turning off. I searched for solutions and didn't turn up anything that seem to help. I checked the normal stuff like fuses and relays. I looked around and found this connector to the headlight motor. When I unplugged everything, I found some serious corrosion. I just cleaned all the terminals and everything works as normal.

http://forums.pelicanparts.com/uploa...1307406302.jpg

http://forums.pelicanparts.com/uploa...1307406319.jpg

That is a good one. Mine is without its cover, and it has a small amount of green corrosion.

N!

How can I get that rear interior panel off for cleaning ground #2 in the rear.

I have searched and a lot of information seems conflicting on removing this 30 year old fragile guaranteed 'Hugh will someone how break this' panel.

Help.

Remove interior the quarter panel
Starts for me by removing by removing the rear seat.
Its quite a good puzzle, actually.
Hard to describe, step by step, from memory.

to get the #2 ground point ,
remove the RR cargo hold down use PB blaster on the screws,
then remove the 2 or 3 screws holding the rear edge and the ones along the floor of the hatch then gently bend the rear edge only far enough out to fit your hand to unscrew the 10mm bolt, it is either on the floor or on the wall just in front of the the taillight housing

I cleaned the #2 post in my 1981 US 5-speed last weekend without removing the entire quarter panel.

Steps:

• Remove toolkit cover
• Remove rear carpet
• Disconnect ground strap
• Remove the passenger-rear side luggage cover hook (2 screws)
• Remove two trim screws from the quarter panel where it attaches to the body almost behind the toolkit cover
• Remove the single screw that holds the panel down to the hatch area floor - on my car, this looked like a wiring bundle tie-down, but was also an attach point for the quarter panel

At this point, I was able to pop the quarter panel end out a couple of inches. This involved popping loose a couple of the trim posts that attach the panel below the rear window.

I could then fit my hand behind the panel through all of the soundproofing to get to the ground point bolt. I used a 10mm combination wrench and a LOT of time to remove the bolt.

Pull the ground wires back to the rear of the car to clean. I got lucky on the install and the bolt threaded properly the first time.

I took about an hour to do this. Turning the bolt with the wrench in these close quarters was extremely tedious and roughed up my hands quite a bit.

Good luck & be careful with this panel! I was rougher with it than I wanted to be but I managed not to break anything.

Yikes.. So this is definitely a saturday morning (cool air and all) project.

I think I will end up removing the seats. Besides, I might find some money or contraband (As I have yet to remove my rear seats in this car and I fear what may be lurking under them...)

Thanks for all the quick and helpful responses..

I now return you to your regularly scheduled forum thread..

'79 splash guards
 

I think this fix might be worthy of this post. My driver side splash guard in front of the tire that protects the headlight and horns was missing when I bought the car. I checked on buying new ones and they were a bit pricey. I remember seeing a post with this idea so I decided to give it a try. Fortunately I had the passenger side one for a pattern, however, that one is in pretty bad shape. I made a cardboard pattern first and used it to trace onto the storage container. Its a hair bigger than the original one so I could trim it back. I also decided not to mess with insulting foam around the edges so I wanted it tight. So far so good, but the true test will be next time it rains (tomorrow).

http://forums.pelicanparts.com/uploa...1308522560.jpg

http://forums.pelicanparts.com/uploa...1308522578.jpg

http://forums.pelicanparts.com/uploa...1308522673.jpg

http://forums.pelicanparts.com/uploa...1308522697.jpg

Nice Mod! Put some Undercoating on that and it will look stock. Great work!

Broken Wheel Locks:

Scene : Your Porsche Factory Wheel locks (the ones that take a 'key' and resemble a 'cap' are stuck (lost key..)

Solution : Center punch the hell out of the key hole until the 'guts' fall out, then using a mangler (screwdriver) mangle it until it comes off.





Broken Wheel 'Nut':

Scene: Some neanderthal that doesn't understand how dis-similar metals disagree used a high torque Impact wrench (your fault) on your Aluminum wheel nuts, OR: Some special needs adult installed the aluminum wheel nuts on the car without anti-seize, and after the years that have passed watching your tires dry-rot you decide its time to remove the wheel, breaking the nut so short that there is not enough remaining to use a proper 'tool' ..The HOrrors!

Solution : Get a 17mm Arbored Hole saw (you will have to remove the centering drill bit). Looks like this http://ecx.images-amazon.com/images/...500_AA300_.jpg

Get 3 or 4 per wheel nut. Get some lubricating oil (light machine oil) and a heavy duty electric drill (put the recharging drill on the shelf this is real -drilling over here).

Carefully slide the hole saw into the hole. The goal is to erode the nut away without scarring the wheel, or damaging the stud. IF you are careful eventually you will erode the remainder of the nut away (use lots of lube, go carefully) to the point you can use a pick tool to get the metal remains out.

Use Eye protection. Metal shards blind people dumb enough not to wear protection everyday.

To prevent this particular form of self induced torture, use the correct antiseize on the ball cup end of the wheel nuts.
A little goes a long way.

Issue: CIS, Hesitation on idle to slow throttle up. Leaning out.

Fix: Replaced faulty WUR and fixed vacuum issue on rear throttle body vac ports. I capped the T that runs vacuum to the Diverter and Decel Valve. Next step is to run a vac test to the Decel where I believe the Diaphragm is bad (vacuum leak).

http://forums.pelicanparts.com/uploa...1311136090.jpg

<iframe width="425" height="349" src="http://www.youtube.com/embed/kjSoLrxn61g" frameborder="0" allowfullscreen></iframe>

Issue: AC does not work when car is in hot weather.

Fix: My Sensor located in the front left portion of the Fender, which is part of the circuit of the AC was not hooked up. I hooked it up and did some mods and some new 2-1/2" Heater Duct Hose. AC now works at any weather.

http://forums.pelicanparts.com/uploa...1310955048.jpg

http://forums.pelicanparts.com/uploa...1310955052.jpg

http://forums.pelicanparts.com/uploa...1310955057.jpg

http://forums.pelicanparts.com/uploa...1310955061.jpg

http://forums.pelicanparts.com/uploa...1310955066.jpg

http://forums.pelicanparts.com/uploa...1310955071.jpg

http://forums.pelicanparts.com/uploa...1310955075.jpg

http://forums.pelicanparts.com/uploa...1310955080.jpg

http://forums.pelicanparts.com/uploa...1310955103.jpg

http://forums.pelicanparts.com/uploa...1310955107.jpg