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Discussion Starter #1
Hello, I recently replaced head gasket and had new vavles put in the head. Now that everything is back togather the car will start and run but will stall when given gas.
If you are light on the throttle you can get it up to about 2500rpms but more than that and it starts getting that bogging sound and stalls or backfires within and stalls.
The idle is a little ruff but when you remove the air line from vavle cover to air duct, it actually smooths out and sounds good.
Pulled plugs and they are black with soot and there seems to be un burnt fuel in cylinders.
I checked timming more times than i can remember before putting it all back together. I have checked for vacuum leaks and all seems right... stuck on this one.

Have went through the normal check list and everything seems to check out....
Vacuum, maf,vvt, fuel pressure, new plugs....
Thats not saying that any of these are not the problem. Just to the point where all the possible culprits are $$$, and want to be wise on where i start.
 

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It sounds like the MAF may not be working correctly or there may be a major vacuum leak in the intake system. To check the intake system for a vacuum leak, attach a vacuum gauge to a full vacuum source. A good place to connect to is the charcoal canister. There should be three hoses connecting the carbon canister. Two of the hoses go to a purge valve that's built into the canister. The second larger hose off the purge valve should be your vacuum line. With the engine fully warmed up, the reading at idle should be 18 - 20 InHg. At 3,000 RPM, it should be around 21 InHg. If readings are under 18 InHg, check the intake manifold nuts to make sure they are tight. The gasket may have failed; spray a water mist at the gasket to see if the gauge reading changes. Also check the intake plenum bellows at the throttle valve and at the MAF for cracks or loose clamps.

You mentioned that the idle is a little rough but when you remove the air line from the valve cover to air duct, it actually smooths out and sounds good. What air line are you referring to; is it the #2 line as shown in the picture below? If so, it's the PCV hose which shouldn't cause any affect. However if it is, then doing a vacuum leak test may bring out an answer.

Perform an ECU code readout with a scan tool to see if any fault codes are set. Have you checked the cam timing to insure that it's correct?

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Discussion Starter #3
It's not the pcv line, the pic shows where it plugs in at the end of valve cover. The other in plugs into breather. That line pulls a major vacuum and thats just straight to the valve cover?
 

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Sup Mod keeping the peace
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During idle or part throttle operation there should be a vacuum being pulled into the valve cover as long as the PCV valve is working properly.
 
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