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9xx
Joined: 18 Jun 2006
Posts: 627
Location: Jarvenpaa, Finland
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 Posted: Thu Apr 14, 2011 11:33 pm Post subject: 931 with no spark at all, looking for ideas |
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In last autumn I drove the car to garage and close the door. Spring came, went back to garage and tried to start the car. No go. Absolutely deas as a stone. There was no issues with the car in autumn.
Situation is this: there is no spark. It has been verified by pulling spark plug wire with spark plug and laying it against the engine while starting. I even tried it from another cylinder to be sure.
Multimeter shows that there is 12V voltage coming from coil terminals when the ignition is turned to ON-position.
Recently replaced items:
-coil
-spark plugs
-spark plug wires
-distributor cap and rotor
-ignition control module
Just today I replaced the ignition switch and swapped some old spare parts to see if they made any difference. But no they didn't, still no spark. I also looked at the flywheel sensor: there was no cracks or rust, it was looking good. Of course you'd have to measure it somehow but I have no clue how...
So what is there left anymore? Siemens DITC?
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Mikko
All gone: 931 '82 Alpine White, original option "220" G31 with LSD + 3 x 944 |
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dpw928
Joined: 02 Nov 2002
Posts: 1860
Location: owasso, ok 74055
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| Posted: Fri Apr 15, 2011 12:49 am Post subject: |
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Check for corrosion on the connector contacts at the DITC and ignition control module.
Dennis
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9xx
Joined: 18 Jun 2006
Posts: 627
Location: Jarvenpaa, Finland
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| Posted: Fri Apr 15, 2011 1:24 am Post subject: |
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Those connections are firm and very clean. Thank you anyway. More ideas?
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Mikko
All gone: 931 '82 Alpine White, original option "220" G31 with LSD + 3 x 944 |
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dpw928
Joined: 02 Nov 2002
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Location: owasso, ok 74055
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| Posted: Fri Apr 15, 2011 2:31 am Post subject: |
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Check the voltage at the coil during cranking.
Dennis
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9xx
Joined: 18 Jun 2006
Posts: 627
Location: Jarvenpaa, Finland
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| Posted: Fri Apr 15, 2011 2:47 am Post subject: |
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Ok, I will. Thanks.
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Mikko
All gone: 931 '82 Alpine White, original option "220" G31 with LSD + 3 x 944 |
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9xx
Joined: 18 Jun 2006
Posts: 627
Location: Jarvenpaa, Finland
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| Posted: Sat Apr 16, 2011 2:11 am Post subject: |
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| dpw928 wrote: | | Check the voltage at the coil during cranking. |
10-11V while cranking. It is bouncing around. At the moment I'm trying to find a spare DITC box.
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Mikko
All gone: 931 '82 Alpine White, original option "220" G31 with LSD + 3 x 944 |
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dpw928
Joined: 02 Nov 2002
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Location: owasso, ok 74055
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| Posted: Sat Apr 16, 2011 4:30 am Post subject: |
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I realize your coil is new but there shouldn't be 12 volts to it with the ignition ON. It should be closer to 6 volts. Have you ohm tested the coil to see if it was in spec? Also, may want to check the continuity of the green wire from the distributor that connects to the ignition module.
Dennis
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9xx
Joined: 18 Jun 2006
Posts: 627
Location: Jarvenpaa, Finland
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| Posted: Sat Apr 16, 2011 4:46 am Post subject: |
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Yes I tested ohm readings from the new coil but from the old spare coil as well (it is a working unit, just old / perhaps original).
Ohms readings were bit different within these two coils, the original coil is closer to Haynes specs. Both are made by Bosch and they are 99 % similar. I guess I start to check wires then...
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Mikko
All gone: 931 '82 Alpine White, original option "220" G31 with LSD + 3 x 944 |
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dpw928
Joined: 02 Nov 2002
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Location: owasso, ok 74055
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| Posted: Sat Apr 16, 2011 5:43 am Post subject: |
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Have you tried starting it with your original coil?
Dennis
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9xx
Joined: 18 Jun 2006
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Location: Jarvenpaa, Finland
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| Posted: Sat Apr 16, 2011 5:51 am Post subject: |
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Yes of course. No spark.
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Mikko
All gone: 931 '82 Alpine White, original option "220" G31 with LSD + 3 x 944 |
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dpw928
Joined: 02 Nov 2002
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Location: owasso, ok 74055
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| Posted: Sat Apr 16, 2011 6:50 am Post subject: |
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Check for spark with the coil wire from the distributor. If still no spark, the problem has to be in the ignition module, green wire or the hall effect portion of the distributor.
Dennis
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RC
Joined: 25 Mar 2007
Posts: 2637
Location: Australia
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| Posted: Sun Apr 17, 2011 10:44 am Post subject: |
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| dpw928 wrote: | | I realize your coil is new but there shouldn't be 12 volts to it with the ignition ON. It should be closer to 6 volts. |
No, not necessarily. Especially unlikely in this case. With NO ground connection to the coil, via the switching transistor in the DITC, the +ve terminal WILL read 12V (nominal). This transistor essentially acts like a set of points, a basic switch. Since the coil is still open circuit the ballast resistor will NOT drop the voltage any, that a DMM will register.
Realistically, parts don`t blow sitting idle but moisture/ condensation/ corrosion does set in. The connections on the low signal pick up side are particularly sus.
| Quote: | 931 '82 Alpine White, original 937 intercooler, G31 with LSD.
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So would your car have the flywheel sensor rather than the dizzy pick up? Sus part anyway, but most probably the connection. Clean, reclean, confirm continuity. ALL connectors on the DITC too. Not sure if the Euro cars have the idle stabiliser, think its just US, but check connectors at ALL components of the ignition circuit.
Sure both coils are OK. They very rarely die, except if left powered on for a time.
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dpw928
Joined: 02 Nov 2002
Posts: 1860
Location: owasso, ok 74055
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| Posted: Mon Apr 18, 2011 7:10 am Post subject: |
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Mikko,
Forget what I said about the green wire and hall effect sensor in the distributor. Some how I thought you had a 79 instead of an 82.  Your 82 should have a crank position (flywheel) sensor that signals the position of the crank for firing. May want to check it and its connections/
Dennis
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78 928 5 sp Silver
78 928 AT Euro Black |
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9xx
Joined: 18 Jun 2006
Posts: 627
Location: Jarvenpaa, Finland
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| Posted: Mon Apr 18, 2011 5:54 pm Post subject: |
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Yes guys there is flywheel sensor in my car. Back to the garage as soon as I get some spare time. I'll be probably receiving another DITC and sensor this week.
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Mikko
All gone: 931 '82 Alpine White, original option "220" G31 with LSD + 3 x 944 |
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