pits928s

I have a 1985 928S that has a hot start issue. After running the cengine for more than about 20 minutes, the car will not start unless it sits for about 10 minutes. After that time it fires up and drives with no problems. Any ideas what might be causing this?

Thank you!

Pits928s

edognight

Does it crank ok after the rest, or struggle to crank at all? I had a similar problem with an Infinity and it was a slow cranking problem, which showed no codes, but the starter and battery were both 1/2 bad, and it wouldn't crank fast enough, though it was barely noticable...

davek9

When was the last time the Crank Position sensor was changed?
Stabbing at it, your issue sounds like an electrical component failure, think fails when hot.
To narrow it down, you need to know whats missing when it won't start (spark or fuel)

zekgb

Replace the Ignition and Fuel Injection relays and report back.

76FJ55

More random guessing: check fuel pressure regulator and dampers for leaking diaphragms.

Speedtoys

Those would have to be SIGNIFICANT leaks...going with BOTH relays first.

pits928s

The car cranks no problem with plenty of battery. Will change out the relays.

andy-gts1

relay, relay , relay...….