A vapor lock issue?, Starting after 30 minutes or so of sitting Options

[boxsterfan]

So on my 74 2.0L D-Jet, my car normally behaves this way on cold start:

1. Starts right up and idles high while cold
2. As it gets warmed up, the idle "hunts" between 0 RPM and 1200 RPM and can occasionally die when pulling up to a stop sign (you might have to blip the throttle).
3. After she warms up, she idles perfect at 900-950 RPM.

The problem:

1. Car is warmed up driving to a store (idling perfect 900-950 RPM)
2. Go into store for 30 minutes
3. Start car (starts for a second but then dies if you didn't give it any gas)
4. Turn key off
5. Turn key right back on and it doesn't want to start (just cranks). But if you give it gas while cranking you can get her to start....almost like push starting the motor and popping clutch).

Note: My fuel pump is in the front. Stainless steel lines in the tunnel.

Am I still experience vapor lock?
Failing CHTS (also related to idle hunting)
Other?

[JamesM]

I have a theory on this problem on both d-jet and megasqirt(using d-jet intake parts and sensors) equipped cars.

What I saw on the Megasquirt equipped car (where I can easily check sensor readings) was that the air temp sensor was getting heat soaked after sitting and was reading the intake temp at near 200 deg. The fuel injection is then leaning out the mixture a ton to compensate for what it thinks is thinner air. Cycling the key on and off a few times on the MS car triggers the prime pulse and would throw enough fuel in to get it to start. On the D-jet car I would pump the throttle with the key on a few times to get the accel enrichment to throw some gas in.

Once started it runs rough until enough air has passed over the temp sensor to cool it off, then all is good.

This was all confirmed with temp readings in Megasquirt, my suspicion is that the same issue affects d-jet

[boxsterfan]

I have a theory on this problem on both d-jet and megasqirt(using d-jet intake parts and sensors) equipped cars.

What I saw on the Megasquirt equipped car (where I can easily check sensor readings) was that the air temp sensor was getting heat soaked after sitting and was reading the intake temp at near 200 deg. The fuel injection is then leaning out the mixture a ton to compensate for what it thinks is thinner air. Cycling the key on and off a few times on the MS car triggers the prime pulse and would throw enough fuel in to get it to start. On the D-jet car I would pump the throttle with the key on a few times to get the accel enrichment to throw some gas in.

Once started it runs rough until enough air has passed over the temp sensor to cool it off, then all is good.

This was all confirmed with temp readings in Megasquirt, my suspicion is that the same issue affects d-jet

Your observation describes my symptoms perfectly. What can be done?