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Tom_15 · Posted: Thu May 22, 2008 3:09 pm Post subject: Loss of Power!

My '24 has had a rough week and is still sitting in the garage not running.

I was cruising along the highway at about 100 km/h when I suddenly lost all power as though the car had been turned off. I quickly turned onto a side road while I still had some speed left and pulled over. I tried starting it a couple of times but it sounded a bit strange and wouldn't go. I instantly thought of fuel pump but I detached it after the filter in the engine bay and it was pumping out strong. I gave up for the night and got it towed home.

While doing some troubleshooting, I got some weird results. My ignition coil was sending a spark across to ground but it's readings with the multimeter were way off. There was no resistance across any of the polls were there was suppost to be some. I borrowed another coil off of a friend which tested normally with the multimeter but it did not change anything and my car still wont start.

Does the ignition coil have to be exact or is something else wrong with my car.

Thanks in advance.
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1978 924 N/A 4-Sp.

Ozzie · Posted: Thu May 22, 2008 4:16 pm Post subject:

IIRC the coil has to be exact.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Min · Posted: Thu May 22, 2008 4:26 pm Post subject:

if you put a spark plug in one of the spark plug wires and set it on the valve cover, does it spark?, if it does, what color is it?

Min
_________________
Custom means it didn't come from a box.
1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.

Tom_15 · Posted: Fri May 23, 2008 2:46 pm Post subject:

I am getting a good purpleish spark from the plug with either of the coils (the old one with the weird readings and the one from my friends drag car)

But when I pulled the plug out to check the spark there was not a drop of fuel on it (brand new plugs from after it stopped working).

I'm thinking that my fuel dizzy might be messed up but it's too dark to do anything else today but i'll attempt to give it a good inspection/test tomorrow.
_________________
1978 924 N/A 4-Sp.

Min · Posted: Fri May 23, 2008 4:31 pm Post subject:

Paul · Posted: Sat May 24, 2008 2:17 pm Post subject:

Did you test the coil with all wires disconnected?
_________________
White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

Tom_15 · Posted: Mon May 26, 2008 2:40 am Post subject:

I tested the spark from the coil and the spark from the first cylinder.

The cap looks newish and I pulled and it looked pretty good inside.

When testing the coil with the multimeter for ohms, I did it connected and disconnected and got the same results.

I'm thinking that since there was no fuel at all on the spark plug when I took it out that there might be something wrong with the fuel system.
_________________
1978 924 N/A 4-Sp.

Min · Posted: Mon May 26, 2008 3:36 am Post subject:

Tom_15 · Posted: Tue May 27, 2008 1:37 pm Post subject:

I tested that and there is no fuel at all going into the injector.

I happened to borrow a fuel system pressure tester that hooks into the top port on the fuel distributer and it showed about 70 psi when i was cranking it over which was within spec. That means that I have fuel at the distributer but not at the injector. Last night I took apart and cleaned the distributer( including all the filters in it) and hooked it up this morning and had the exact same results.

What else could be wrong with my erratic toofah!
_________________
1978 924 N/A 4-Sp.

Ozzie · Posted: Tue May 27, 2008 3:47 pm Post subject:

You have to lift the air plate.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Min · Posted: Tue May 27, 2008 5:07 pm Post subject:

Lift the plate for sure(was in my instructions), if that has no effect on the injector spray, then while the plate is lifted, put your hand under there and see if you can feel the plunger from the distributor, it should be coming out of the distributor when the plate is lifted, its possible your plunger is jamming in the distributor, if this is the case, no fuel will flow.

Min
_________________
Custom means it didn't come from a box.
1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.

Tom_15 · Posted: Mon Jun 02, 2008 2:36 am Post subject:

Hey. when the plate was lifted it did push out fuel.

I was out of ideas until I did a top dead center check and it was not matched up with the dot on my crankcase. I looked at my timing belt and it was really worn out so I figure it must have slipped. I put a new one on after adjusting the crank and my car is finally back on the road.

Thanks min and ozzie
_________________
1978 924 N/A 4-Sp.

Min · Posted: Mon Jun 02, 2008 5:47 am Post subject:

Good work

Min
_________________
Custom means it didn't come from a box.
1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.

Ozzie · Posted: Mon Jun 02, 2008 1:54 pm Post subject:

No Prob.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance