it has a miss and stimbles when you just push the gas a little bit and just dosnt sound like it allways has , i have checked plugs ,coils have changed pdfe,egr,iac,tps what else could cause this ..i was thinking the intake maybe has a leak but not sure how to tell , also the motor gets hot while its doing this

 

i see these 2 spots at the mounting flange of the intake

 

Your check engine lights gotta be on. Retrive the stored codes most auto parts store will pull them for free. Whats the exaust smell like? sounds to me more like a head gasket.

 

Someone used rtv sealant instead of a gasket and has been into the thermostat at one point or another. Another sign there may have been an overheating issue in the past. That looks like a minor leak and would not cause the conditions you explained. Are you getting any white smoke out the back? Loosing coolant?

You must have a CEL on like jethat said... no?

 

no codes at the moment ...and the thermostat i have replaced , and it does smoke but not verymuch ...the leak in the front is the only one i can see so there could be others...also when i unhook the green vac line that hooks to the egr it runs better but still can tell buy the sound

 

and just looked at what i can see of the rest of the flange and it looks the same like wet but not wet with dirt/sludge build up all the way around the lower intake flange...can i reuse the stock gaskets , or are they not like the newer ones ,,cause i can tear down the motor and see if the gasket is broke or damaged somewhere..cause to me it seems like a vac leak cause when i give it some gas it acts like not anuff gas or to much air

 

'If' the motor is a 5.4L you have coils over plugs.
'If' the miss/shudder is in OD at light throttle, one of the coils is faullty.

 

i know i have cop's and have been checked..the miss is in park and any gear..also the oil isnt milky so i dont think its a blown head gasket

 

and when you 1st crank it up it runs fine then starts to miss

 

Its possible and likely for the head gasket to only leak in the combustion chamber. Usually it also leaks compression into the cooling system to. the check engine light is not on at all? I would go have the codes read antway something might be wrong with the CEL. If you have a solid miss you SHOULD have a CEL..

 

I would take a compression test looking for a weak valve, then when you do the intake gasket seals you know to pull the head for a valve job. A miss always coming when the motor has warmed up leads to a burned exhaust valve seriously and will eventually break causing internal engine damage. Jump to that if you have one cyl low of compression when tested wet. If your compression is good look to a bad catz and relieve that side of pressure to see if the miss goes away. It should throw a code though for catz/O2 problem.

 

Two things, please do not 'say' it can't be this or that 'because they were checked', until the problem is found.
It might run clean cold, until the pressure in the cooling system builds with heat and forces coolant into one or more cylinders such that the plug can't fire any longer.
The cooling system builds pressure above 14 psi that can be helped into the cylinder on the intake stroke.
You have to understand that parts change dimension with heating and cooling. If there is a leak it may either be closed when cold then open up with heat or the other way around.
At the very least a good scanner can register the cylinder/s in missfire and give you a place to start.

 

i have my own scanner and like i said before there is no code , also i have seen blown head gaskets and there is no water in the oil or pouring out the muffler ...coils check when cold and hot spark plugs pulled time after time and nothing wrong with them , like i said it acts like a vac leak and as shown the intake show's a leak from somthing

 

also just checked the egr soleniod and it get vacuum and dosnt let any past it ...so could this cause this problem

 

well did a search of pic anf found that im no the only one with the leak on the intake like that so im pulling the intake