 |
 |
 |
|
|
 |
| Search | Car Forums | Gallery | Articles | Helper | Air Dried Beef Dog Food | IgorSushko.com | Corporate |
 | | ||
| |
|
| Latest | 0 Rplys |
|
|||||||
 |
 Show Printable Version |  Email this Page | 
Subscribe to this Thread
|
|
|
Thread Tools |
05-07-2010, 07:32 PM
|
#1 | |
|
AF Newbie
 Join Date: Dec 2004
Location: Shakopee, Minnesota
Posts: 12
Thanks: 0
Thanked 0 Times in 0 Posts
|
98 Silverado Z71 5.7l Vortec
I've got a 98 with a 350 Vortec that is running really rough. I noticed a hissing coming from the top of the intake manifold and used some carb cleaner to narrow down the trouble. There is an area where the fuel inlet / outlet come into the manifold. One of these was loose. I got them seated back in and it didn't solve my problem. That's when I noticed that the plastic piece where the fuel lines go in would physically move when pressure was applied. I can't believe this would be normal... Has anyone else run into this problem? Any help in fixing it up or advice on whether or not i need to replace the whole manifold would be greatly appreciated. Thanks!
|
|
|
|
|
05-13-2010, 10:13 PM
|
#2 | |
|
AF Enthusiast
Join Date: Feb 2005
Location: cuyahoga falls, Ohio
Posts: 1,070
Thanks: 0
Thanked 4 Times in 4 Posts
|
Re: 98 Silverado Z71 5.7l Vortec
Sounds like the throttle body is loose? Need to be more descriptive.
__________________
ASE Master Certified before the age of 20 Current Cars: 2001 Chevy Silverado 1500 Z71 5.3L 1996 Acura Integra LS B18 1.8L Past Cars: 1990 Buick Estate Wagon 5.0L 1987 Chevy S10 2.5L Tec Four 1995 Pontiac Grand Am 2.3 Quad 4 1996 Jeep Grand Cherokee Limited 5.2L AWD 1991 Ford Tempo L 2.3L 1992 Buick LeSabre 3.8L 1997 Buick Century 3.1L 1996 Lumina APV GT 3.4L 2006 Ford Escape 3.0L XLT |
|
|
|
|
|
05-14-2010, 07:12 AM
|
#3 | |
|
AF Enthusiast
 Join Date: Jan 2004
Location: Muscoda, Wisconsin
Posts: 884
Thanks: 0
Thanked 2 Times in 2 Posts
|
Re: 98 Silverado Z71 5.7l Vortec
You may just need the upper intake gasket set. I think the movement is somewhat normal because of the bracket that holds the CSFI unit. The gaskets in the upper intake are just o-ring type rubber material
http://gsi.xw.gm.com/image_en_us/gif.../066/66929.gif In the picture, you are saying part #12 is loose, #11 is the gasket I mentioned. #12 just snaps into a bracket on the lower intake manifold, its not the greatest setup and I think I shimmed the bracket up when I switched from the CSFI to the GM upgrade because I couldn't get it to seal |
|
|
|
|
|
05-24-2010, 11:42 AM
|
#4 | |
|
AF Newbie
Join Date: Dec 2004
Location: Shakopee, Minnesota
Posts: 12
Thanks: 0
Thanked 0 Times in 0 Posts
|
Re: 98 Silverado Z71 5.7l Vortec
Yeah... part #12 is what appears to be loose. I haven't had much time to dig into this more, but plan on being out there this week to get it finished.
What does GM offer for an upgrade? |
|
|
|
|
|
05-28-2010, 09:05 AM
|
#5 | |
|
AF Enthusiast
Join Date: Jan 2004
Location: Muscoda, Wisconsin
Posts: 884
Thanks: 0
Thanked 2 Times in 2 Posts
|
Re: 98 Silverado Z71 5.7l Vortec
The upgrade is an assembly that replaces the CSFI poppets with injectors. The CSFI unit has injectors in the piece that you say is loose and hoses run to poppet valves that are inserted into the lower intake manifold, the updated setup has the injectors inserted into the lower intake manifold, I think the cost is around $400 now, plus labor if you dont do it yourself
|
|
|
|
|
|
|
POST REPLY TO THIS THREAD |
 |
|
|
