Vacuum leaks - ZR-1 Net Registry Forums

cuisinartvette · 08-27-2005

As I was browsing the "Buying a Zr-1" I stumbled across this:
Check for a vacuum leak. Open hood, turn ignition key on but don't start the car. Listen for vacuum pump to come on which is located under front right headlight. It should come on only for a few seconds and turn off. If pump stays on or comes on every few seconds then you have a vacuum leak.

I noticed (with the key on and the engine off) an intermittent noise coming from under the pass.side headlight while waxing the car (90). It would come on a few times per minute, a second or two at a time. Secondaries and lines were replaced before I bought it. Could I have a vacuum leak? Car runs fine, no problems that i can tell.

Aurora40 · 08-27-2005

How often is it? I'd think if it were like 30 seconds or more that this might be normalish? That's the secondary vacuum pump, though. Mine comes on for an instant about every 3 seconds... definitely leaking.

cuisinartvette · 08-27-2005

I'll check after work today;hope not, don't want to tear into it just yet.I'll post what I find tonight

Z Factor · 08-31-2005

So did you determine how often it comes on?
As was said it will cycle on now and then, but if you have it going every 15 seconds or so, it has a leak.

cuisinartvette · 08-31-2005

I haven't had a chance to check it, put it back in storage for the time being. I'll check it at some point this weekend, have to go get my stare on

Scoob · 08-31-2005

I just checked mine...it cycles every 35 seconds with the key on and motor off.

WB9MCW · 08-31-2005

CAV looks like ur ok per scoob's check!!! good to go!!!

cuisinartvette · 09-01-2005

I'll check into it Sunday, let you know what I find. Thanks, Scoob!

Scoob · 09-01-2005

Quote:

Originally Posted by cuisinartvette

I'll check into it Sunday, let you know what I find. Thanks, Scoob!

I think over 25 seconds is good. When I first got mine it was cycling every 10 seconds or so. If you do have a leak it's not a panic situation but should be addressed. Just be sure to get all the parts you need (lines, gaskets)before you pull the plenum.

Nick · 09-01-2005

I replaced all of the vacuum hoses under the plenum of my '94 last year. My pump barely comes on at all, and the car runs great.

08-27-2005	#1
cuisinartvette Join Date: Aug 2005 Location: San Fernando Valley, CA. Posts: 896	Vacuum leaks As I was browsing the "Buying a Zr-1" I stumbled across this: Check for a vacuum leak. Open hood, turn ignition key on but don't start the car. Listen for vacuum pump to come on which is located under front right headlight. It should come on only for a few seconds and turn off. If pump stays on or comes on every few seconds then you have a vacuum leak. I noticed (with the key on and the engine off) an intermittent noise coming from under the pass.side headlight while waxing the car (90). It would come on a few times per minute, a second or two at a time. Secondaries and lines were replaced before I bought it. Could I have a vacuum leak? Car runs fine, no problems that i can tell. __________________ 1990 ZR1, 142,000 miles-Black on black 4.09's Haibeck chip, 3"exh, K&N, meth inj. Last edited by cuisinartvette; 08-27-2005 at 10:49 AM.

08-27-2005	#2
Aurora40 Join Date: May 2005 Location: Leesburg, VA Posts: 2,713	How often is it? I'd think if it were like 30 seconds or more that this might be normalish? That's the secondary vacuum pump, though. Mine comes on for an instant about every 3 seconds... definitely leaking. __________________ Bob Saveland Former owner of #2517 [IMG]http://a.random-image.net/aurora40/vette.jpg[/img]

08-27-2005	#3
cuisinartvette Join Date: Aug 2005 Location: San Fernando Valley, CA. Posts: 896	I'll check after work today;hope not, don't want to tear into it just yet.I'll post what I find tonight __________________ 1990 ZR1, 142,000 miles-Black on black 4.09's Haibeck chip, 3"exh, K&N, meth inj.

08-31-2005	#5
cuisinartvette Join Date: Aug 2005 Location: San Fernando Valley, CA. Posts: 896	I haven't had a chance to check it, put it back in storage for the time being. I'll check it at some point this weekend, have to go get my stare on __________________ 1990 ZR1, 142,000 miles-Black on black 4.09's Haibeck chip, 3"exh, K&N, meth inj.

08-31-2005	#7
WB9MCW Join Date: Dec 2003 Location: McHenry, Il. Posts: 6,607	good to go CAV looks like ur ok per scoob's check!!! good to go!!! __________________ http://i119.photobucket.com/albums/o...9mcw/SIG-2.jpg http://i119.photobucket.com/albums/o128/wb9mcw/vcm.gif "The Budget should be balanced, the Treasury should be refilled, public debt should be reduced, the arrogance of officialdom should be tempered and controlled, and the assistance to foreign lands should be curtailed, lest Rome will become bankrupt. People must again learn to work instead of living on public assistance." - Cicero, 55 BC " We the people are the rightful masters of both Congress and the courts, not to overthrow the Constitution but to overthrow the men who pervert the Constitution." - Abraham Lincoln

08-31-2005	#4
Z Factor Join Date: Dec 2003 Location: S. Florida Posts: 2,667	So did you determine how often it comes on? As was said it will cycle on now and then, but if you have it going every 15 seconds or so, it has a leak.

08-31-2005	#6
Scoob Join Date: Aug 2005 Posts: 34	I just checked mine...it cycles every 35 seconds with the key on and motor off.

09-01-2005	#8
cuisinartvette Join Date: Aug 2005 Location: San Fernando Valley, CA. Posts: 896	I'll check into it Sunday, let you know what I find. Thanks, Scoob! __________________ 1990 ZR1, 142,000 miles-Black on black 4.09's Haibeck chip, 3"exh, K&N, meth inj.

09-01-2005	#10
Nick Join Date: Jul 2005 Location: Auburn, Washington Posts: 586	I replaced all of the vacuum hoses under the plenum of my '94 last year. My pump barely comes on at all, and the car runs great. __________________ Nick ZR-1 Net Registry Founding Member #32 - lapsed...