Replacing the Head Gasket.
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Intermediate
Joined: May 2005
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Replacing the Head Gasket.
Well looks like my head gasket is leaking, I have been having problems with the car cutting out when i push the gas, I thought it was bad fuel at first but it's not, changed the fuel filter, checked spark plugs and wires, cleaned the distributor. Going to check the compression on the heads tomorrow but it is more than likely that one of the gaskets is the problem. I have a L98, anyone do this before, any tips before diving into this?
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Plugs were not wet, no water in the oil, but the past few weeks I have been losing water and wasn't sure where to, no leaks on the ground. The car idles really rough now and whenever I try to push the gas down a little bit, it just starts to choke out. When I started it up it was smoking a little bit, but I think that was just water burn off. This is going to be a long weekend.
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what a pain. 
I tested for leaks in the head gasket by hooking up a compression gauge. All cylinders checked out fine and held pressure, so that eleminates replacing the head gasket, which is a good thing. While I was at it ,I changed the spark plugs. Tried starting it up again but it was still giving me problems, try to rev it up and it chokes out. And I can't get any speed at all on the road. So then I thought it was the fuel, I took all the fuel out and put in 5 new gallons. No luck. Another funny thing is that when I get out of my car, 5 mins later the security alarm will activate, without locking the doors. So if I try to open the door, the alarm will go off. 
My car has just gone crazy. So I'm thinking this is a fuel problem, but I have no idea where it could be, I will take it into the shop and see what they think it is. I can already feel my wallet getting thinner.
I tested for leaks in the head gasket by hooking up a compression gauge. All cylinders checked out fine and held pressure, so that eleminates replacing the head gasket, which is a good thing. While I was at it ,I changed the spark plugs. Tried starting it up again but it was still giving me problems, try to rev it up and it chokes out. And I can't get any speed at all on the road. So then I thought it was the fuel, I took all the fuel out and put in 5 new gallons. No luck. Another funny thing is that when I get out of my car, 5 mins later the security alarm will activate, without locking the doors. So if I try to open the door, the alarm will go off. My car has just gone crazy. So I'm thinking this is a fuel problem, but I have no idea where it could be, I will take it into the shop and see what they think it is. I can already feel my wallet getting thinner.
Thread Starter
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Joined: May 2005
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Just got news back from the shop. They said that both of the Catalytic Converters are bad and need replaced. So I guess, does anyone have recomendations on where to buy them, I was thinking of also upgrading to a new exhaust system, maybe Borla Stingers.
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Melting Slicks
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From: Belews Creek north carolina
St. Jude Donor '05
i believe mid america has them for your car 
1984-91 Free Flow Catalytic Converters
Replace worn or damaged catalytic converters and retain your Corvette's stock status with our EPA-approved unit for 1984-91's. Direct bolt-on installation allows the freedom (and savings!) to do the job at home. Your engine will run cooler?even your interior will be cooler.
Part Year Description Price Availability
603-926 1982, 1984-85 Catalytic Converter $149.99 In Stock
603-928 1986-91 Catalytic Converter $149.99 In Stock
603-930 1980-82, 1984-91 Hose, Converter Connector $9.99 In Stock
1984-91 Free Flow Catalytic Converters
Replace worn or damaged catalytic converters and retain your Corvette's stock status with our EPA-approved unit for 1984-91's. Direct bolt-on installation allows the freedom (and savings!) to do the job at home. Your engine will run cooler?even your interior will be cooler.
Part Year Description Price Availability
603-926 1982, 1984-85 Catalytic Converter $149.99 In Stock
603-928 1986-91 Catalytic Converter $149.99 In Stock
603-930 1980-82, 1984-91 Hose, Converter Connector $9.99 In Stock
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
Originally Posted by 91vettemo
Just got news back from the shop. They said that both of the Catalytic Converters are bad and need replaced. So I guess, does anyone have recomendations on where to buy them, I was thinking of also upgrading to a new exhaust system, maybe Borla Stingers.
You actually have three cats on your (assumed) 91 - two precats and a main. If the pre-cats have broken up, you can bet the main is clogged. If you don't need to pass a visual, just eliminate the pre cats and install a three stage, high flow main.
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Yup I have a 91. They said it would be $800 a piece at the shop, so I said no to that. I'm confused now though, at mid america they have the "1984-91 Free Flow Catalytic Converters" which myvettesblue was talking about. Would I need one or two of these, or three? Steel Blue 91, are you saying I should just take off the precats and make it straight pipe then install a high flow main? Where would I buy this at? Sorry I'm just a little confused on all of this. Also would this do any damage to my headers if I took off my pre cats?
Thanks guys!
Thanks guys!
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
You're talking stock exhaust headers, right? No problem - the "Y" pipe (which contains the pre-cats - one left one right) attaches to the exhaust manifold and runs to the main cat. All I had the muffler shop do when they installed my new main was to cut the pre-cats out of the "Y" pipe and weld in a section of pipe in each side.
Starts out looking like this:
Ends up looking like this:
$800.00 for parts and labor (even for a Y pipe with cats) seems real high to me.
Starts out looking like this:
Ends up looking like this:
$800.00 for parts and labor (even for a Y pipe with cats) seems real high to me.
Thread Starter
Intermediate
Joined: May 2005
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Ya I have stock exhaust headers. What is the advantage of using the precats? I think I will just get or try to make the y pipe, unless precats will help performace somehow. Also, at madvet which main CAT should I get. Go here to view them Can you tell me the difference between 603-926 and 603-928. Which one should I get? Thanks!
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
603-928 will fit your car. With the newer technology, the pre-cats are not needed to pass the sniffer test. Depending on where you live, the visual inspection might be a problem.