Hi I have a 2004 dodge ram 1500 FWD I recandely had a valve spring brake on passenger side, cylinder 4 intake. I got a brand new head for it and put it all back together. it started up and ran very poorly, I later relisted I had put the intake on it wrong I had pinched the wire from the wire harness underneath it and a peace from the foam shed under the intake was covering up one of the intake ports. I fixed that but that did not correct the problem. It still ran very poorly. It also was puffing smoke, so I put a new EGR valve in it but this did not correct the problem, it make the smoke go away but that was it. However the ETC light had came on so I put a brand new ETC on it and the light went off, Then it was throwing a code for a coolant temperature sensor I put that in it it still, wont idle proportion, and I am out of ideas could someone please help me.

 

Did you compression check all the cylinders, particularly after installing the replacement head? Perhaps start there.

 

I just did that today and the number 4 cylinder had zero compression, I took the valve cover off and the valves seam to be opining properly.

 

That narrows it down. Perhaps that originating valve spring failure also resulted in a dropped valve kissing the piston, resulting in a cracked piston on #4. Sorry Did you inspect the piston and cylinder while the head was off for repair/replace? Regretful that it seems it has to come apart again.

 

Yes I did do that and it's all good.

 

Pump the cylinder full of air with both valves closed and do a leakdown test. AKA, see where the air is going. Intake, exhaust, crankcase, ETC.