Ok, I having a little bit of a problem. I am just starting to Mod my Truck slowly, I have already added a K&N Drop and I just added a Flowmaster 50 Series yesterday. Here's the problem, When I start from the line, or when I pump the gas in Park, it seems to mis fire between 1500 to 2200 RPM. Just started doing this about 300 Miles ago. I thought it might be the tranny but it does it even if I pump the gas in park. Does any body have any clues. I haven't tried looking to the plenum gasket, could this be the problem?

Thank,

DMan.

 

COuld be a few things. Injecters, or even anything of your ignition components.

 

May want to check the routing of your wires, maybe touching and causing the miss. I would make sure all plug & distributor boots are secure and the coil wire is secure also. How old are the plugs, wires, cap and rotor?

 

Ok, I just looked and it does look like the plenum gasket could be out, still not sure if this is what causing my problems. Ok, it looks like I am going to be changing the plenum gasket, now the question, I have heard to some Intake Manifolds do away from the gasket, Like Mopar and Edelbrock's ( I Think), for the money would it be wise to just order a Intake Manifold, or just replace the gasket? At looking at the price it's a few hundred more for the intake, What benefits would I get with replacing to whole intake. I was looking at summit Racing and found a Edelbrock's Performer RPM Air-Gap intake manifold for less then $300, Is this a good intake? Any Problems with intakes would I lose any low end or gain top end. Any comments would help.

Thanks again,

DMan

 

u 100% sure that it is your plenum, if its bad you see oil leaking in from the gasket, there should be a little debris and grim down there because the breather house routes back into there.

 

plenum gaskets are more likley to cause high idle. Backfires can be cause be the lack of backpressure, esspecially when you jump into the throttle.

 

clogged cat?

 

nah, more like a freeflowing exhaust. Backpressure is a funny thing, you will always hear those high performance engines backfire cause they run open pipes just about. My jeep had the same thing, it would backfire when I jumped on it when it was out of gear. 4 bangers with high flow cat and flowmaster muffler...