Car: 2000 Acura Integra LS. Built motor, gt28rs turbo, log manifold.

Hello, it's been awhile since I posted, hopefully you guys can help me solve or narrow down this issue.

Cold start: no problem fires up every time
While driving: no issues, no lights
Turn car off and turn it right back on, it fires up fine.

If I drive the car around 30 minutes - 1 hour and turn it off and let the car sit for 10 minutes and try to start it up all I will get is a humming sound, no cranking or turning over. This doesn't happen all the time, but has a good probability of happening.

The car will eventually start back up on it's own, but can take awhile and seems to take longer in warm/hot weather than cool days.

If I jump the car it'll start right up immediately and drive as if their was no issue at all.

Items recently replaced: battery, starter (both around 6 months ago), main relay (2 years ago). I drive the car a couple times a month so not many starts on these items. This issue has happened both turbo'd and n/a but is more prone to happening when the car is turbo'd so I thought maybe something is getting heat soaked like the starter but hadn't read anything like that on the forums.

Sorry for the long post, but I know there is a huge range of reasons of why a car won't start so wanted to be as descriptive as possible. Thank you.

 

if the engine won't even crank (spin) at all, it's either a bad starter or bad ignition switch.

 

I'll take a look at the ignition switch. Thanks!

 

or a starter relay.

 

Take a piece of 10g wire with you and next time the problem happens jump the solenoid with the wire. If it starts right up then you just pinpointed the issue to the starting circuit.

 

thank you for the advice on how to check it. I'm off tomorrow so I'll try this out.