1984 3.2 warm starting issues

[Keithg]

Any ideas why our Targa will start quickly when cold but take 2-3 starts to turn over when warm?

[PeteKz]

I'm not a 3.2/DME expert, but I would start by checking the resistance curve of the head temp sensor. I don't remember if the 1984 has a separate cold start valve. If it does, check that opearation.

[Rtrorkt]

I chased this issue for a while, replaced O2 sensor, ICV and head temp sensor (royal PITA). Finally found a maladjusted idle mixture screw

[ant7]

It could be something as simple as a worn O-ring on the idle adjust screw, and or the mixture screw in the AFR adjusted incorrectly.
Air leaks etc.
If the head temp sensor is faulty, the car will usually start fine when cold, however; the car will most likely be running very rich when hot, hence when you switch off and try to re-start' the engine will be way too rich, and will most likely foul the spark plugs.
Easy way to check is to pull the white plug socket in the engine bay near left intake manifold, [there are three, two black, one white] and short the pins in the plug, with a clip and see if the car starts easier when hot.
Ant.

Originally Posted by Keithg

Any ideas why our Targa will start quickly when cold but take 2-3 starts to turn over when warm?

[Magyar Kiwi]

Hi
Poor warm starting can be caused by loss of residual pressure in the fuel manifold when the engine is turned off.
See link below and test per post 42.
Hoping this helps.
Cheers
https://forums.pelicanparts.com/porsche-911-technical-forum/1042004-carrera-3-2-fuel-pressure-regulator-removal-3.html