Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Post Reply
 
LinkBack Thread Tools Display Modes
Old 04-24-2023, 06:14 PM   #1
Registered User
 
Join Date: Aug 2019
Location: Austin, TX
Posts: 42
Newly purchased 1998 986 making a "whoop" sound occasionally at startup

Hi all,

Just picked up a 1998 986 with 72K miles in Nevada after my 2000 l986 with 103K miles and an LN IMS bearing that I had owned for 3.5 years lost to Tahoe that cut a corner too close.

Test drove and checked out the '98 and all seemed fine: frankly, looks like a museum piece.

Anyhow, after starting and stopping several times and getting it up to operating temperature for a sustained period, it has started to occasionally started to make a momentary what I can only describe as a "whoop" sound that lasts for a second or two at the most. It seems to come from the back of the car/engine compartment, and it sounds to me tike an "air" issues rather than a mechanical one (maybe the oil separator as that seems like a common air intake issue? does the car have an air pump as it sounds a bit like the air pump on my Land Rover D2).

Any idea what this could be?

austinporsche is offline   Reply With Quote
Old 04-24-2023, 07:15 PM   #2
Registered User
 
Join Date: Sep 2008
Location: Florida
Posts: 2,492
The car does have an air pump but it should only be active for the first minute or two after starting the car.
dghii is offline   Reply With Quote
Old 04-24-2023, 07:25 PM   #3
Motorist & Coffee Drinker
 
78F350's Avatar
 
Join Date: Jul 2014
Location: Oklahoma
Posts: 3,653
Garage
Loose spark plug?
https://986forum.com/forums/performance-technical-chat/77965-986-normal-engine-noise.html
__________________
I am not an attorney, mechanic, or member of the clergy. Following any advice given in my posts is done at your own peril.
78F350 is offline   Reply With Quote
Old 04-25-2023, 03:07 AM   #4
Registered User
 
Join Date: Mar 2007
Location: Ohio
Posts: 1,997

There's two vids in that thread—or at least there's supposed to be. The 2nd one seems to be no longer available. I do some of my own stuff on my car, but I'm certainly no seasoned mechanic, but I don't hear anything much different on the remaining 1st vid than what my car has sounded like for the past 80K miles.

The comment later on about the "chirp" sound is what I experienced with loose plug(s), including the description, by pilot, of hearing it at low revs when blipping the throttle (or briefly on normal acceleration from a standstill). I didn't hear it at all at high revs, and it did go away when I replaced the plugs. (I would have just tightened them, but they were due for replacement.)
Frodo is offline   Reply With Quote
Old 04-25-2023, 04:55 AM   #5
On the slippery slope
 
JayG's Avatar
 
Join Date: Mar 2014
Location: Austin and Palm Springs
Posts: 3,793
Garage
Where in Austin are you?

If you need a good indy for service, I can give you an excellent recommendation
__________________
2004 Boxster S 6 speed - DRL relay hack, Polaris AutoTop DIY
2004 996 Targa Tip
Instructor - San Diego region
2014 Porsche Performance Driving School
2020 BMW X3, 2013 Ram 1500, 2016 Cmax, 2004 F-150 "Big Red"
JayG is offline   Reply With Quote
Old 04-26-2023, 03:27 PM   #6
Registered User
 
Join Date: Nov 2019
Location: Virginia
Posts: 2
Starter?

https://www.youtube.com/watch?v=MdwZDmZOhKQ

Not exactly sure what Whoop means. Starter going bad has this screech or squeal sound. Just had my 1999 (original owner) 986 starter replaced today.
__________________
1999 Boxster - Silver/red (original owner)
2017 718 Cayman S - Black/black & red
Bill in VA is offline   Reply With Quote
Old 04-27-2023, 12:18 PM   #7
Registered User
 
seningen's Avatar
 
Join Date: Jul 2008
Location: austin
Posts: 823
I"m halfway between Austin and Dripping Springs if you want someone else to give it a listen?

The Starter is a likely candidate at startup -- sounds like a whirl to me -- before the solenoid disengages.
__________________
Drivers: '15 Panamera Hybrid (wife's), ' 01 996 GT2, 00 Boxster S, '96 993 Çab/Tip (wife's)
Race Cars: '75 911 RSR Replica & '99 Spec Boxster
mike@lonestarrpm.com
seningen is offline   Reply With Quote
Old 04-28-2023, 02:04 PM   #8
Registered User
 
Join Date: Aug 2019
Location: Austin, TX
Posts: 42
Thanks, all.

To the Dripping-Austin guys, I am out on Bee Cave Road.

I am now pretty confident that it is the starter, so going with that replacment.
austinporsche is offline   Reply With Quote
Old 05-20-2023, 03:25 PM   #9
Registered User
 
Join Date: Aug 2019
Location: Austin, TX
Posts: 42
Replaced starter, no more "whoop" (maybe more like a whir like some described, like a cable being pulling out of a winch really quickly, probably a more accurate description of the sound).

Pinion gear retraction spring was clearly weaker on the starter I pulled out than on the new starter.
austinporsche is offline   Reply With Quote
Old 05-20-2023, 03:27 PM   #10
Registered User
 
Join Date: Aug 2019
Location: Austin, TX
Posts: 42
On to the next issue (ambient temp sensor)

austinporsche is offline   Reply With Quote
Post Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 03:55 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page