924Board.org

[ace924]

hi all ive just bought a porsche 924 1982 for a project and ive always wanted 1 as a child.
i bought it know ing had a fuel problem i was told it was running really rich and when hot it wouldnt start unless you put jump leads on and keep it turning over eventually it started but when cold a few turns and away it went but very slow no power (but i am used to a 400bhp subaru)
a mate said its not firing right so today i changed plugs leads and dizzy cap now i cant get it running at all it tries buts miss fires really bad and when i removed the new plugs they were very wet and black looked oily but smelt like fuel.
i hope ive explained this ok i am new to porsche but can turn a ford or subaru engine inside out in a day so dont mind getting dirty
please help thanx alot

[Ozzie]

Definitely running rich.
do a search and look for your answers. been asked many times.

Tuning the CIS is not a black art. If you want it perfect you need a CO tester but you can get it running reasonably well without it.
As the UK doesnt have a catalytic converter the exhaust pipe is a good indicator. If it is black and sooty- too rich.
Whitish grey - too lean. Dark grey - just right.

Other fuel problems could be- leaky injectors or cold start valve, bad WUR

Double check your valve and ign timing as well.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

[ace924]

thanx mate i have search before i posted and still am but cant find no help.
never mind thanx anyway

[9XX Girl!]

ace924 This may help, Bosch Technical Book(CIS) K-Jetronic (Free Download)
It takes a while to download but should be a good read for you (so keep trying)
You will find your answer to the hot start problem here http://www.924.org/techsection/hot_start_problem_fix.htm

Hot Start is a well debated topic as these cars love presenting this fault,
Look http://www.924board.org/viewtopic.php?t=30733&postdays=0&postorder=asc&highlight=hot+start&start=0
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924 (84) N/A 2 ltr - 5 Speed - BLACK - Project (looking for 200BHP, any ideas!)
924 (81) N/A 2 ltr - 3 Speed Auto - SURINAM RED (Metallic) - Near Original Spec (sticking with originality)
BOTH ON THE ROAD, BOTH USED EVERY-OTHER DAY

[ace924]

thanx 9xx girl i checked timimng it all lines up tdc then set dizzy cap to lead 1 everything is in order .
it just want run without my foot on the pedal and sound really rough more like a twim and engine shakes alot.

[9XX Girl!]

[ace924]

thanx alot i will try that but as i said ive fitted nes dizzy cap leads and plugs but thanx i will try that now

[9XX Girl!]

Double check you timing first by "static timing method".

Line the notch on the inside edge of the crank pulley wheel with the pointer on the water pump.
(you can turn the crank pulley with a 24mm socket - make sure you turn it the correct direction - to check direction, put the car in top gear, drop the hand brake and push the car forward a little and note direction)
Check the dot on the inside edge of the cam wheel lines up with the pointer on the cam cover. (if not turn the crank wheel another 360 deg)
Look through the oil filler to make sure both inlet and exhaust valves are in the up (closed) position.
Remove plug #1 and put it back on the HT lead then earth the plug, (so that you can see it spark)
Put a screwdriver down the spark plug hole to check your piston is at TDC.
Now undo the dizzy clamp.

Right now turn on the ignition and rotate the dizzy slightly back and forth. The rotation action should cause the #1 plug to spark if all is correct.
If it does, you have spark timing close. (TDC) remember you need it to be at 10 deg Before TDC to get it running right
_________________
924 (84) N/A 2 ltr - 5 Speed - BLACK - Project (looking for 200BHP, any ideas!)
924 (81) N/A 2 ltr - 3 Speed Auto - SURINAM RED (Metallic) - Near Original Spec (sticking with originality)
BOTH ON THE ROAD, BOTH USED EVERY-OTHER DAY

[9XX Girl!]

You have got the leads on right haven't you?


_________________
924 (84) N/A 2 ltr - 5 Speed - BLACK - Project (looking for 200BHP, any ideas!)
924 (81) N/A 2 ltr - 3 Speed Auto - SURINAM RED (Metallic) - Near Original Spec (sticking with originality)
BOTH ON THE ROAD, BOTH USED EVERY-OTHER DAY

[ace924]

again thanx alot i cant thank you enough for this help.
timimg is bang on leads are on in the correct order . i dont quite understand the 10 degree part ?? if i couls get it running enough to get to my local garage would help.
before i changed the leads plugs and cap it started and ran on just wouldnt start when hot without draining the battery (needed leads)
to be honest i never noticed it wasnt firing right it was a mate who said to change all the leads and stuf ??

[Mike924]

Firstly, even when it's running great, a 924 won't ever feel as quick as a 400 bhp Subaru!

The CIS has two 'weak' points. One is the WUR (warm-up regulator) and the other is the accumulator.

The WUR provides the enrichment function when the engine's cold. When it stops doing that (usually because the valve clogs/rusts up), unscrupulous sellers sometimes compensate for this by turning up the richness adjustment at the fuel distributor to at least get the car to start. The consquence of this is that it engine runs very rich once it's warmed up.

One of the main functions of the accumulator is to maintain pressure in the system while the engine cools after it's turned off, to prevent vapour locks in the fuel lines. The infamous K-jet hot-start problem is usually cause by a leaky accumulator.

Unfortunately neither of these items cheap. Doubly unfortunately there is no substitute to replacing these items. Whilst used, working WURs can be had, I'd steer clear of used accumulators. From my (not so) extensive research into the matter, it appears the diaphragm in the accumulators becomes leaky with age...
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1985 Porsche 924 'Lux', Kalahari Beige (my ex)
1993 Porsche 968 Coupe, Midnight Blue, 6 spd

'There is no substitute for a little grease under your fingernails.' - Chrenan, 924board.org

[ace924]

quick update folkes...
got car running to what seemed really good no problems . park it up leave it a while go back to it and i get the old flat battery syndrome ???
so i played with the dizzy a bit hey presto starts wicked i though again got it hot left it go back and started problem solved ???? nah not a chance lol
this time i went for a good drive after a while it started what i can only discribe as firing on 3 struugling to move .
any ides folks please ???

[Smoothie]

One sign that the starter solenoid is gunked-up (dirty) is that it'll kick in and turn the engine when cold, but will not when the engine's hot. -And you won't even hear a click (because the solenoid can't move).
I would put the timing back to where it was when it was running good.
Next time it won't start when warm/hot, give it more time to cool, and see if that alone doesn't get it to go. If it does start after more cooling, it's very likely time for a new solenoid.
Other things to check/clean are the battery post connections, battery(-)-to-chassis grounding, wiring to the starter (924NAs often develop hidden corrosion within the insulation of these wires), and (+)wiring to the alternator, its' grounding(-), and alt. belt alignment and tension..
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"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox