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Misfire after changing intake manifold

cloby

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Hello all. I recently changed my stock 2 barrel 318 in my 1972 Coronet to a Holley 600 and Edlebrock 2176 intake manifold. It developed a dead miss. I checked all the wires and the firing order and it was all in line. The car is a daily driver and sat for a little while while I waited for parts. Could it have fouled a plug by just sitting after running every day? It didn't have the misfire before I changed it but the 2 barrel on it was pretty well cooked. When I put the new gaskets on I changed the ones on the ends too because they were on the old intake. I also changed the valve cover gaskets. Any help is much appreciated.
 
Is the carb new or old? If old rebuild. Spray carb cleaner on the edges of intake and base of carb and see if the RPMs go up. If so vac leak. I had a small vac leak on mine and it took me for ever to realize it. My car would not idle below 1000rpm.
 
Is the carb new or old? If old rebuild. Spray carb cleaner on the edges of intake and base of carb and see if the RPMs go up. If so vac leak. I had a small vac leak on mine and it took me for ever to realize it. My car would not idle below 1000rpm.
It's refurbished from Holley. Thank you for the carb cleaner idea though. I will definitely do that and see if the RPM goes up.
 
It's refurbished from Holley. Thank you for the carb cleaner idea though. I will definitely do that and see if the RPM goes up.
Did you use the seals on the front and back or just black RTV ?
 
The first time I used seals and rtv,2nd time just the rtv.
 
The first time I used seals and rtv,2nd time just the rtv.
Could using seals and RTV be a problem? I made sure to not go overboard with the RTV but did get good coverage for all my seals.
 
Everyone is different on this. Some say use seals other say not to. My friend builds engines and doesnt use them. Because I had the leak I decided not to use the seal the second time. I used a lot of rvt with the seal them wiped of excess.
 
Everyone is different on this. Some say use seals other say not to. My friend builds engines and doesnt use them. Because I had the leak I decided not to use the seal the second time. I used a lot of rvt with the seal them wiped of excess.
I used them because it came with the gasket set. It sounds like it also has what some people call spark knock. I'm going to check around the carb and the gaskets like you said to do but I just wanted to give you a little more information on what it's doing and what I did when I did the install. I'm sorry if I sound a little dumb about this but I'm still a little bit new to mechanics.
 
Its not a dumb question, you should see all the things I ask. Thats what this forum is about,helping each other. Good luck and let us know what it was.
 
Its not a dumb question, you should see all the things I ask. Thats what this forum is about,helping each other. Good luck and let us know what it was.
I really appreciate the help. I sure will
 
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