924Board.org

[griffinbilt]

1982 924 Turbo. Has anyone ever had one that will idle but as soon as you crack the throttle it shuts down the ignition but if you let go back to idle it will continue to run? Thanks Tony G. griffinbilt@gmail.com

[ideola]

I've not seen that specific issue. It sounds like fuel delivery problem, either directly with the fuel pumps, or something in the fuel pump circuitry. It's possible that it might be related to the throttle position switch and related wiring, although I would not expect that to cause complete loss of ignition or fuel.

First thing I would do is bypass the overboost protection switch to eliminate it as a variable, and then double check ALL of the wiring at the coil and battery. DITC does NOT like flakey grounds or dodgy electrical repairs. I've seen several 931s where the wire for the overboost switch is either loose or frayed, which can cause intermittent fuel delivery problems as the connection goes in and out with vibration. You need to eliminate this first before going any further. It is quite simple to do, just disconnect from the overboost switch on the charge tube, and ground the terminal to the intake, head, or alternator.

Next, I would unplug and reseat the large black multi-pin connector at the DITC box. Then I would unplug and reseat the connector at the igniter circuit board just behind the LHS headlight.

After that, I would systematically work through the entire fuel delivery system. See this thread: http://www.924board.org/viewtopic.php?t=28790
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erstwhile owner of just about every 924 variant ever made

[griffinbilt]

Dan I have re adjusted the TPS,The overboost is already by passed. It will actually go bang out the exhaust if you crack the throttle to open and if you close it quickly the engine will come back to life go bang in the exhaust and idle.Sounds to me that the ignition is turning of beyond idle?. Just put a crank sensor in it [used] just to get it running again but at idle only. ? Thanks Tony
The fuel system is like new. This is the car that I had at 2013 Parade.

[ideola]

Have you inspected the black multi-pin connector at the DITC box? It can be the source of a multitude of problems. At minimum, you should disconnect it, and then firmly reseat it.

Better yet, open up the black receptacle, take a picture of the insides so you can see which lead goes where, and then pull each female receptacle out of the black connector. Using a pair of small needle nose pliers, very carefully and gently squeeze each female connector. You don't want to squash them fat, but you need to squeeze them ever so slightly so that they grip the male connectors on the DITC box more firmly. Once you've done this, and reassembled the connector, firmly reseat it to the DITC. Then, I would recommend using some large zip ties (you may have to double them up), wrapping them lengthwise around the silver box so that they firmly hold the connector in place.

Why Porsche didn't require a locking mechanism for that connector just baffles me. I mean, they put one on something as non-critical as the Lambda connector, why couldn't they have done something similar for something that is required for the car to stay running?!
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erstwhile owner of just about every 924 variant ever made

[griffinbilt]

Guys, Is there anyway that the crank sensor could be working only for TDC and not giving the DITC a running RPM? Just wondering.

[ideola]

Yep. There are two coils in the sensor, one that measures the sintered insert (TDC) and one that counts the teeth (speed). If one of the coils went bad, this is what you would get...
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erstwhile owner of just about every 924 variant ever made

[griffinbilt]

Thanks Dan. I guess I will persue haveing crank sensors made. Found a guy that is a Siemens guy how many of these are needed for the 931 S-2 guys?

[Chaos]

Hey griffinbilt, any update on this at all?

My car actually just developed what sounds like an identical issue...
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'81 US 931 "Rochelle"