924Board.org

[Boostsideways]

I tried everything recommended earlier for my car suddenly dieing then not starting up again problem.. nothings worked. Car sounds the same. Everything's clean, looks good, the sensor is on tight etcetc.. battery's good..
What would be 'causing my ignition control unit and 12v resistor to keep blowing? 'cause according to my VM tests both were giving bad signals.. does this car have like a main CPU thats probally screwed, IE reason all my fuses keep blowing, weird readings from everything..?
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Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

[tuurbo]

Time for MegaSquirt?

I think some of the old farts on this board advise people to sort of 're-do' the soldering on the main 'computer'.

What are 'IE reason' and 'VM tests'?
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1980 924 turbo, MSD, Meth. Inj, otherwise stock.

[fiat22turbo]

It is pretty obvious that you have some sort of electrical short. It is likely under the dashboard. Fuses only blow if they are overloaded the connection is shorted directly which causes the fuse to overload and fail (to protect the system)

Time to pull the seats and the battery, line the floorboard with pillows (so you can lay on your back under the dash and walk upright the next day) and start disconnecting connections, cleaning the contacts and reconnecting them. Along the way, check the wires for broken or burnt insulation. Any connections that look suspect, replace/repair properly. You may have to (carefully) pull the center console, glove box, etc to get to all of the wiring/connectors.

There is a computer of sorts, but I'm not sure where exactly it is on the 931, a search here should turn it up, if someone doesn't post it directly.

Follow all of this under dash wiring work with cleaning all of your connections under the hood. Start at the battery and ensure you have a clean, solid connection at the battery posts (use a battery brush), move outward from there, checking and cleaning every single connection you come across. Don't forget the alternator and starter connections and the headlight connections. Again, look for brittle, broken insulation, burnt wires, loose connections.

Give the connections a gentle tug, they should be solidly fixed to the wire, if it comes off, you either pulled too hard or you had a bad connection.

To repair the connection, post here what failed and post pictures (photobucket, flickr, etc are free for posting pictures) and we'll tell you the best way to deal with that situation.

Good luck!
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[ideola]

It might sound extreme, but if you're going to do what fiat22turbo suggested, you might even consider pulling the dash. It's really not as daunting as it sounds. With it out of the way, you'll be spending much less time on your back with a flashlight, and you'll have much better visibility into where there are cooked wires, corrosion, etc. You'll be surprised at what you'll find, trust me.

While you have the dash out, do some preventive maintenance. Like replacing the heater core, and maybe even removing the A/C (unless you intend to get it functioning again). At this point, you might as well go for it. The car isn't driveable as is, and you'll never get any money out of a non-running 931.
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erstwhile owner of just about every 924 variant ever made

[Brockoli]

+1 to ideola's idea. Its cramped up there.

IE reasons = for example the reasons for my fuses blowing. IE(i.e.) is latin for something(i think), same as e.g. lots of profs use these notations.

Mega squirt might be an option. CSI is expensive to replace, the amount of $$$ I put into mine I could of done mega squirt. Just a thought.

My car had intermittent idle problems, ended up being a bad connection on the distributor. I cut off the stock plug and put generic female electrical ends on and havent had a problem since. Its a long shot its the same problem.
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'80 924 M471,Wideband O2, Full coilover susp,23/19 sways,Bilstiens,KLA Strut Brace,Roll Bar,Test Pipe,BBS RS, Willwood BBK

25% of a '87 944 Chumpcar http://straightpipe.ca/forums/showthread.php?t=2454

'79 924 Sebring Edition(Sitting)

[ideola]

[Brockoli]

ideola - thanks for clarifying 4 years of university notes for me

that is a very interesting view on CIS vs EFI. I agree completely with you. With my car, it had not been started in 5-10years. And if someone neglects a car like that, they probably didnt put any fuel stabilizer in it.

And in hindsight, the cost of repairing my CIS system would of been the same price as an EFI conversion.
Fuel pump = 250
fuel injectors = 250
AAV+TTS+CSV= 300
fuel accumulator = 180
total = ~$980 and i know I am missing something
EFI = ~$1000-1250

However, in Boostsideways situation, his CIS was running. So CIS, I would assume would be less expensive to repair if like what ideola said "one can properly diagnose the problem"
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'80 924 M471,Wideband O2, Full coilover susp,23/19 sways,Bilstiens,KLA Strut Brace,Roll Bar,Test Pipe,BBS RS, Willwood BBK

25% of a '87 944 Chumpcar http://straightpipe.ca/forums/showthread.php?t=2454

'79 924 Sebring Edition(Sitting)

[ideola]

[morghen]

does it have AC? wanna sell it?
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Supercharger and EFI kits
https://www.the924.com

[CorsePerVita]

don't give up on the car, challenge yourself, you can do it!
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- 1977 Porsche 924 2.0 N/A (Trackday Project)
- 1979 Porsche 924 2.0 N/A (The other daily)
- 1980 Porsche 931 (Daily)
- 1987 Lamborghini Jalpa
- 1999 Ducati 900SS

[Chrenan]

[Scorpio]