Weird sound for a second after starting
 

Hi,

My '86 944 NA makes a weird noise for about a second after you fire it up. After this, the sound is completely gone and it revs and drives perfectly.

I've uploaded a video below:
https://www.youtube.com/watch?v=6eMPGlXdYOs

Have not noticed a drop in power or performance and it sounds perfectly normal while driving. Oil consumption has also stayed the same (1/1000 L/km but this is presumably because of an unrelated issue with the AOS rubber which has been going on for a while). I cannot determine where the sound is coming from, it's pretty loud. Checked the ignition & fuel system but couldn't find anything obvious.

It happens when the engine is both cold and warm, but sometimes you don't hear it.

Any ideas? Thanks!

I am by no means an expert mechanic, but to ME it sounds like the starter motor is doing something a little wacky in between turning the engine over and retracting the starter gear.

It's that K&N sticker that's causing the ruckus :D

I'm going to jump in with Bradical and say your starter probably has some sort of bearing issue of some sort because it certainly sounds like it could be something rotational that has grenaded inside itself. I wouldn't worry about the engine because it sounds beautiful to me.

I'm unable to watch the video at work, but can say from experience that sometimes the bendix on the starter motor kicks out to engage the flywheel, but doesn't always come back into the stop position right away after starting the car. The solenoid is responsible for this movement, and might be sticking.

Thanks for the responses. I was also thinking the starter, to be more precise the solenoid not disengaging the motor properly. Will inspect this further when I put the car on a lift. Doubt it would be something with the engine, only thing I could think of was low oil pressure when starting causing hydraulic lifters to make a noise.

@GTR34 It was on the car when I bought it. Maybe I'll swap it out for the original filter.. one day..

I was only kidding, even if you put it there, it's your car so mod away :)

Bendix not retracting after engine start. flywheel now turning the starter. R&R the starter. Engine sounds great by the way!

Starter....

As posted above, it's the Bendix...