I have been the owner of a '87 Audi 5k SQ for about 2 years. Despite the fact that I'm living in Alabama and have no AC, I have formed a tight bond with this car and it has quite a personality:-)

Anyhow, I've always had trouble starting the car, especially after a long rain. The starter is engaging just fine, but the engine just doesn't want to turn over. However, after a day or two of sitting in the sun 'drying out', the vehicle usually started without issue...until a few days ago.

The vehicle has been sitting for about 4 days now (drying out) and the weirdest thing is happening. When I go to start it, it will turn over almost immediately, rev to about 1.3k RPM for a second or two, and then just stall out and die (regardless of whether I step on the gas petal or not). Trying to restart the car only leads to the starter engaging and the engine NOT catching.

If l leave the car alone for a few hours or overnight, the same thing happens, starts once, dies, then will not catch again.

Because I used to only have trouble starting during/after wet conditions, I thought it may have been an ignition problem or an electrical short, but now that everything seems dry, I wonder if it might not be getting enough fuel or it may even be flooded - I have no idea....and the last thing I want to do is tow a 22 year old car to a mechanic.

I really have no practical experience with fixing cars other than preforming routine maintenance (oil changes, spark plugs, etc.). But I am very savvy when it comes to researching fixes (on the web) yet haven't found too much with this kind of symptom.

This is what I've done so far...

Checked distributor cap...no moisture/bone dry
Checked back seat for leaks...somehow rainwater is leaking into the cabin and accumulating under the rear bench near the ABS control unit.

Like I said before, I've always had trouble starting the car, even in dry conditions, the car would want to die unless I basically floored the gas petal. Or if it did die, it would at least restart without much trouble, and after it had been running for 2-3 minutes, it would have no issue keeping a steady idle... which led me to think that I needed to replace the Engine Coolant Temperature (ECT) sensor.

I know this is a long post, but I'm desperate for any advice/help at this point since I can't really afford to spend more than $500 bucks right now and avoiding a tow is paramount. Here are some pics:

 

the first thing you should check with all Audis with mechanical fuel injection,is to make sure there are no vacuum leaks, check the hose to the throttle body for cracks, an also all of the hoses connected to the intake, they especially like to crack at the junction where about 4 or 5 hoses come together at the back of the valve cover, hope this helps.