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Discussion Starter #1
Hey guys, my 88 Shelby Z is stalling.

It's happening just after I turn the car on from cold and only just after driving it the tiniest bit, such as from the parking spot to a stop sign, maybe 20 ft away. If I go a bit farther, such as down my street off of the driveway which is maybe 100 ft, I don't see the issue.

The car runs fine after restarting, and I'm getting good fuel economy (I've done a 200km round trip with it). I can't find any vacuum leaks and there are no codes, so I'm not really sure where to look next. It's not a serious issue because I know the car will start and run again no problem, but it's a little embarrassing!
 

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Is the cold idle speed OK? The IAC should catch a stall before it occurs, is it responsive and varying the idle speed as an engine load (like the A/C compressor) comes in and out?
Maybe check the plug tip color right after the first cold stall. Black could indicate rich or misfiring plugs. Light could indicate normal or lean. Secondary ignition health (including rotor, cap, wire and the correct "Champion" plugs) is important as firing voltage requirements are much higher when cold.
There are some DRB II IAC tests to see if the PCM and IAC can track a selected idle speed on the DRB successfully.
There was a TSB on carbon build-up behind the intake valves that could result in a cold, lean condition. Much of the fuel from the injectors would spray into the carbon instead of going into the cylinders. It would soak up into the carbon deposits like a sponge. In cold open loop, the O2 sensors won't yet compensate for the missing fuel and as the carbon saturates with liquid fuel, then the problem goes away.
We use a laproscope down the throttle body to view the back of the valves. Modern quality fuel with cleaners and solvents should keep carbon build-up to a minimum or you can try a bottle of Techron in the tank for a couple of tankfuls.
 

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Fault codes?

How many miles ago was the last tuneup (specifically the ignition rotor and wires)?
 

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Discussion Starter #4
New wires, cap, rotor, plugs and air filter at the beginning of march. I only put premium gas into the car, but I could try running some cleaner. There are no fault codes other than the expected 33.
 
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