Vacuum leak?
Racer
Joined: Sep 2006
Posts: 389
Likes: 1
From: Roswell GA
You can also use throttle body cleaner.Definitely check for lines on the back of the intake. Seems like the spots you can't see are where the lines always get a hole.
Thread Starter
Intermediate
Joined: Sep 2007
Posts: 36
Likes: 0
From: anthony NM
Thanks for all your help. I did replace some damaged hose.I still have a leak behind the intake. I am worried about pulling hose, that I cant see. Are there any DIY threads out there for this that have pics or diagrams? Also the rpms kick up in neutral when driving, and return to normal after being stopped for several seconds with the brake depressed. will fixing the leak fix this also? Thanks for sharing your time and wisdom. I am very new to vettes, and all your advice is invaluable to me. -Nick
Melting Slicks
Joined: Aug 2007
Posts: 2,721
Likes: 4
From: Elizabethtown
hey, i had a vacuum leak a while ago. Are all the PCV hoses connected?
Check the back of the intake manifold, there is two hoses that connect to the back of it, the brake booster hose is on the driver side and there is another tiny hose on the passenger side. check to make sure they are both connected
Check the back of the intake manifold, there is two hoses that connect to the back of it, the brake booster hose is on the driver side and there is another tiny hose on the passenger side. check to make sure they are both connected
Instructor
Joined: Dec 2003
Posts: 174
Likes: 0
From: bothell wa
You may have a defective power brake assist
Thanks for all your help. I did replace some damaged hose.I still have a leak behind the intake. I am worried about pulling hose, that I cant see. Are there any DIY threads out there for this that have pics or diagrams? Also the rpms kick up in neutral when driving, and return to normal after being stopped for several seconds with the brake depressed. will fixing the leak fix this also? Thanks for sharing your time and wisdom. I am very new to vettes, and all your advice is invaluable to me. -Nick
Racer
Joined: Sep 2006
Posts: 389
Likes: 1
From: Roswell GA
Thanks for all your help. I did replace some damaged hose.I still have a leak behind the intake. I am worried about pulling hose, that I cant see. Are there any DIY threads out there for this that have pics or diagrams? Also the rpms kick up in neutral when driving, and return to normal after being stopped for several seconds with the brake depressed. will fixing the leak fix this also? Thanks for sharing your time and wisdom. I am very new to vettes, and all your advice is invaluable to me. -Nick
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Melting Slicks
Joined: Jan 2002
Posts: 2,754
Likes: 0
From: Nokomis FL
Check the hose from the PCV to the throttle body. Mine had a hole I could stick my finger in on the back side where you couldn't see it. Happened over night I think one day it wasn't there next day it was. Chased that demon for a week before I found it with a can of TB Cleaner.
Racer
Joined: Sep 2006
Posts: 389
Likes: 1
From: Roswell GA
I agree, you should never use carb cleaner on our cars. Throttle Body/EFI Cleaner is much made different for a reason. I was told our throttle bodies have a coating on the inside that carb cleaner could strip. Same thing with our no carburated cars.
Race Director
Joined: Nov 2003
Posts: 16,062
Likes: 4,148
From: Bergen county NJ
if your air conditioning switches vents Ie. floor, windows or center vents then you don't have a leak at the vacuum line behind the manifold which is a bitch to get at..(or so my tech told me)
The 3/8 inch fuel line hose (I think thats the size) around the pcv valve can get a hole.. and can be bought at any autoparts store..
Buy a new pcv...replace the hose? about 10 bucks total..
Let us know how you make out and what resolves your issue..
The 3/8 inch fuel line hose (I think thats the size) around the pcv valve can get a hole.. and can be bought at any autoparts store..
Buy a new pcv...replace the hose? about 10 bucks total..
Let us know how you make out and what resolves your issue..
Thread Starter
Intermediate
Joined: Sep 2007
Posts: 36
Likes: 0
From: anthony NM
My air conditioner does switch and works corectly, I have checked and or replaced all my hoses. I think it is the intake manifold gasket, because with the brake cleaner the idle still changes when I spray behind the intake. I have replaced pcv valve and hoses. Any idea what dealer would charge to replace intake manifold gasket?
Thread Starter
Intermediate
Joined: Sep 2007
Posts: 36
Likes: 0
From: anthony NM
took it to the stealership today, they replaced intake manifold gasket, and there is still a leak. the dealer says that they dont know what is wrong because it is heavily moded. there is no performance shop in my area that works on vettes, and all the work that was done to it was done 800 miles away. I gave the dealer the list of mods, and the phone number to the shop that did the work. The mechanic said that even with the vaccum leak it is the fastest vette he has ever driven. the modsare as follows: mti stealth II Cam 116, stage 2 heads, high flow airbridge, kooks headers, kooks x pipe with cats, corsa tiger shark, vararam air intake. oes anyone know if if any of these could cause a difficult to detect leak to the rear of the motor? Any help on this would be very appreciated
Thread Starter
Intermediate
Joined: Sep 2007
Posts: 36
Likes: 0
From: anthony NM
Dealer called this morning. warped intake manifold is the final diagnosis. he also said that because the filter in the vararam intake was in such poor shape it really junked up my throttle body. that is causing my high idle problem. I just bought this car from a texas ebay dealer 800 miles away, and was told that the car was inspected prior to sale. to do the recomended repaires at the dealer it would cost me over $2,000. The car was also advertised as having new ( rebuilt) motor. Do I have any recorse. I didn't buget for all these repairs, and really extended my self to buy what I thought was my dreamcar.
Race Director
Joined: Nov 2003
Posts: 16,062
Likes: 4,148
From: Bergen county NJ
Maybe it was just the filter on the air filter..
Have you done a search on warped manifold.
I've never heard that before. (not saying its not possible but rather I've never heard of that before)
Try a search here and over at www.ls1tech.com
Let us know what you find.
Have you done a search on warped manifold.
I've never heard that before. (not saying its not possible but rather I've never heard of that before)
Try a search here and over at www.ls1tech.com
Let us know what you find.
