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Discussion Starter #1
What's up guys. Merry Christmas to all.I changed out my Edelbrock airgap to a Weiand single plane 7532 and 1205 intake gasket. Car ran excellent before (should of left it alone right) just wanted to go with a single plane intake. Car does not want to idle now surges from 3000 and tries to shut off. Timing is 18-19 at ldle and 35 total. Noticed #1and#2 is not firing. WHY!!!!! Thanks for any info.
 

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If it has no fire to the plugs I would start with checking the distributor cap and rotor. I would also check the plugs themselves. Sometimes when changing a intake you can get oil or moisture in a cylinder that can kill the plug on initial startup. It is possible that your intake change has nothing to do with your problems but I suspect a intake gasket problem. What head are you running. Most aftermarket heads have bigger ports and a 1206 gasket just fits better. When I put my car together I used a 1205 because it's what I had. I was never comfortable with it and when I started having a small leak at the front seal area I used that as a excuse to put another gasket on it. When I took it apart I realized I had had a small gasket problem from the start. The 1205 was too small and I wasn't getting a good seal. My car didn't smoke, miss or idle funny but I could tell a difference when I changed the gasket.
 

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Yep definitely sounds like a vacuum leak. Either from the intake gasket or carb base. Spray some brake cleaner along the intake while it’s running. It will pick up speed when you spray over the leaking area.
 

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If the intake was leaking wouldn't there be oil or antifreeze leaking out or antifreeze in the oil? Also why isn't #1and #2 firing?
A vacuum leak is where the engine is sucking unmetered air. Doesn’t have to be leaking coolant. The coolant ports aren’t very close to the intake ports. Gasket could have shifted or sagged down. If the engine is idling high and won’t come down to a slow idle...be it’s a vacuum leak..
 

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No spark at the plugs or they just look not to be firing? I had an intake gasket leak changing intakes a while back. Gasket was soaked with oil. Motor still ran ok but the plugs on the front passenger side were very dark. Turned out to be a warped intake on that side. Strange you have 1 and 2. Intake possibly warped front to back or not sealing up front for some other reason. Doesn't seem like cap or rotor but 1 does fire right after 2. I was trying to get a motor to start years ago. Tried everything, even had spark to the plugs. Finally I put in new plugs and it fired. The old plugs looked ok but I guess I'd loaded them while trying to get it to start.
 

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Discussion Starter #10 (Edited)
We'll changed out#1 and #2 plugs still the same ****. Firing order is good. Engine surges to around 3000 then shuts down wont hold an idle. Seems rotor not making contact with#1 and #2 for some reason since they are next to each other, but car ran good before I swapped out intake.
 

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We'll changed out#1 and #2 plugs still the same ****. Firing order is good. Engine surges to around 3000 then shuts down wont hold an idle. Seems rotor not making contact with#1 and #2 for some reason since they are next to each other, but car ran good before I swapped out intake.
If you have compression and spark on 1 and 2 it should be firing. But if those cylinders are lean due to a vacuum leak...they won’t fire as even as the others...usually your headers primaries for those lean cylinders will glow red if they are lean. Lean is hot...
 

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Check those 2 plug wires with a ohm meter . Happened to me number 1 was dead and I thought all the worst then I checked the plug wire and it was dead .
 

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I know it would be a PITA, but why not change back to the old manifold and see what happens. Maybe it's something to do with the manifold, since that's the only part that has been changed. That would also let you see if there is a problem with the intake gasket.

The symptoms do sound like a lean condition on 1 and 2. maybe the new manifold isn't allowing proper fuel distribution.

I'm curious as to what you find.
 

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what heads do you have? Specifically the intake runner size? The 1205 gasket is for a "performance port" and may be too large for your heads.
Being the correct size for your intake is immaterial if the bottom of the gasket slightly exposes the valley. In that case, you won't be able to detect the vacuum leak with either carb cleaner or propane.
I would consider the 180 Brodix to be a performance head and it uses an 1204 gasket.
 

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what heads do you have? Specifically the intake runner size? The 1205 gasket is for a "performance port" and may be too large for your heads.
Being the correct size for your intake is immaterial if the bottom of the gasket slightly exposes the valley. In that case, you won't be able to detect the vacuum leak with either carb cleaner or propane.
I would consider the 180 Brodix to be a performance head and it uses an 1204 gasket.
If it is sucking vacuum from the lifter valley (crankcase) you can pull the pcv valve from the valve cover. Then put your fingers over the breather holes in the valve covers or oil fill cap. There will be a vacuum there and suck your finger if the vacuum leak is into the crankcase.
 
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