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dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

Try retarding ignition by a few degrees (turn distributor clockwise) to see if that helps. If too advanced it can slow down the cranking rpm and cause a cold nonstart. Removing one spark plug lets it crank faster allowing the other cylinders to start.

Dennis
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81 931 5 sp
78 928 5 sp Silver
78 928 AT Euro Black

rat · Posted: Sun Oct 14, 2012 5:11 am Post subject:

Interesting theory. It could just about tie up with the observations I've made. I.e. that a tired battery added to the likelihood of non-start, and the sole observable difference between 3 and 4 plugs present was a slight increase in cranking speed.

Ozzie · Posted: Sun Oct 14, 2012 10:25 am Post subject:

CSV should run about 8 seconds IIRC.

If you connect an earth to red/white cable with a switch this will enable you to fire it at will. (use only for testing)
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Muz924 · Posted: Tue Jun 25, 2013 4:20 pm Post subject:

The weather has turn cold and an old problem has re-surfaced!

After starting normally over summer, my no start problem is back

I get strong cranking with no fire, I tried the pulling out spark plug #1 and still no start.

I am getting no spark and hence no fuel pump starting. I get 10.5v at +coil when cranking but no voltage at -terminal of coil.

I swapped over to an old coil and she fired up with problems, re-connected to new coil and she starts up OK!

Problem occurs with both coils and is fixed only by swapping them around.

The problem must be before the -terminal of the coil which would be ignition control box or distributor.

Any ideas would be appreciated.

I am running the standard 1980 breakerless (no points) type distributor.

Cheers,
Santo
_________________
1978 924 RoW 5-Speed (Current Project)
1980 924 RoW 5-Speed (Donor Car)
1985 Alfa Romeo Alfetta GTV 2.0 (Previous Project Car)

Ponz · Joined: 10 Jan 2013 Posts: 229 Location: Florida

make sure the wires are on right firing order.
_________________
77 1/2 track car
79 931 Euro
87 911 Targa

Ponz · Joined: 10 Jan 2013 Posts: 229 Location: Florida

make sure the wires are on right firing order.
_________________
77 1/2 track car
79 931 Euro
87 911 Targa

Muz924 · Posted: Sun Jun 30, 2013 7:28 pm Post subject:

Yeah, the wires are spot on, when it starts its runs perfectly.

Started up fine this morning....starting to do my head in

Next time it plays up i will check and see whats happening at the ignition control box.

Cheers,
Santo
_________________
1978 924 RoW 5-Speed (Current Project)
1980 924 RoW 5-Speed (Donor Car)
1985 Alfa Romeo Alfetta GTV 2.0 (Previous Project Car)

Muz924 · Posted: Sat Jul 27, 2013 7:54 pm Post subject:

Ahhh, this is doing my head in!!

The problem keeps on changing, currently it starts up it runs on three cylinders.

I have narrowed it down to no spark at No.4.
I have replaced spark plug, lead & even swapped around 3 differant coils...still same problem.

The only way i can get No.4 to spark is by removing the lead from the distributor cap & once i have approx 10mm gap i get a big spark and the engine runs nice and smoothly of all 4 cylinders. When i move it closer or connect it back onto the distrubutor cap the spark stops again.

Does anyone have any ideas whats going on?
_________________
1978 924 RoW 5-Speed (Current Project)
1980 924 RoW 5-Speed (Donor Car)
1985 Alfa Romeo Alfetta GTV 2.0 (Previous Project Car)

dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

Have you checked the interior of your distributor cap for cracks or signs of arcing? Also, have you checked your valve and ignition timing?

Dennis
_________________
81 931 5 sp
78 928 5 sp Silver
78 928 AT Euro Black

Muz924 · Posted: Sun Jul 28, 2013 4:02 pm Post subject:

Hi Dennis,

All the "consumable" parts are new, valve clearances were ok last time i checked, It starts and runs fine in the warmer weather.

I don't understand why i need to make the High Voltage jump through a 10mm gap to get it to spark plug to fire.
In other words it prefers a higher resistance to fire.

I cant help thinking its a faulty ignition module, unfortunatley i dont have spare one to interchange.

Looks like i am going down the MSD ignition path.

Cheers
_________________
1978 924 RoW 5-Speed (Current Project)
1980 924 RoW 5-Speed (Donor Car)
1985 Alfa Romeo Alfetta GTV 2.0 (Previous Project Car)

Muz924 · Posted: Mon Aug 12, 2013 9:24 pm Post subject:

OK,

I think i might have solved the problem

I kept swapping plugs & leads until i got the problem to re-occur on a different cylinder. Problem seems to have been the spark plug!! What stuffed me up was the plug that i was swapping around was also faulty.
So i had 3 good & 2 bad (NGK BP6ES) i was rotating around.

I kept getting a crap orange spark with the plug out and sitting on valve cover. I then grabed an old Bosch WR6DC i had in a box of old spare parts and got an good strong blue spark. I put it in and she starts and runs on all four

Tried it again today and it starts and runs OK.

The car is not registered yet and so I start it up once a week making sure it warms up with the thermo fan kicking in and out.
I guess this can stuff up spark plugs as all the NGK plugs i have I bought new with no real driving done on them!

1 step closer to getting on the road !
_________________
1978 924 RoW 5-Speed (Current Project)
1980 924 RoW 5-Speed (Donor Car)
1985 Alfa Romeo Alfetta GTV 2.0 (Previous Project Car)

Muz924 · Posted: Wed Jun 25, 2014 10:14 am Post subject:

Ahhhh,

Weather has turned COLD here in Melbourne Aus & my no spark when weather is cold has returned!!!

The car has been starting first time every time over the warmer months.

I still think its the ignition control box, might get an MSD and give that a go.

Cheers
Santo

Gave her a polish the other day....at least she looks good!

_________________
1978 924 RoW 5-Speed (Current Project)
1980 924 RoW 5-Speed (Donor Car)
1985 Alfa Romeo Alfetta GTV 2.0 (Previous Project Car)

morghen · Joined: 21 Jan 2005 Posts: 9095 Location: Romania

Maybe you could borrow that box from someone else for a quick try?
When something mallfunctions why think of modifications? why not just replace the bad part and keep the car original.
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Supercharger and EFI kits
https://www.the924.com

Ozzie · Posted: Fri Jun 27, 2014 7:35 am Post subject:

I took the box off mine and it had rusty screws holding it on.
As this is also how it gets it earth ( none in the wiring) I replaced them. I also fitted an earth wire to the body of the box to chassis.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

pmcaya2 · Joined: 24 Nov 2005 Posts: 191 Location: Scio, NY USA

I'm somewhat hesitant to suggest this, but its a quick and easy check.

Since you start the car periodically and don't drive it in weather - I wonder what would happen if you start the car and gently spray water on the engine with a garden hose. If it starts to miss or die, you'll know the problem is electrical.

One other check: swap out the coil wire - it does 4X the work as the plug wires and failure sometimes gives hard to diagnose problems.

I hope this helps. - Peter