You should probably just listen to your husband, woman!

On a serious note, does anyone have any experience with the flowmaster merge collectors? It seems they are the ideal size/shape (pending the same diameters as the dual to single) to directly replace the cat.

 

Took the truck to a muffler shop yesterday, they diagnosed the Cat as good...thank goodness! Tried to replace the downstream O2 sensor, but couldn't get it loose...seems to be rusted. Gonna try some PB Blaster & see what happens. Did get the plugs all changed & a loose vacuum line reattached.

 

A major vacuum leak would also cause the problems you described - but should have generated a CEL if severe enough to cause performance issues.

The PB Blaster if you let it soak in should let you get that sensor out, but be advised you need to clean that area - threads, etc. REAL well before installing the new sensor. Lubes, and especially petroleum based ones will foul the sh*t out of a sensor...

 

It was the breather hose off of the airbox. o2 will be changed out today. I tried talking her into replacing the cat with a cutout.. not sure she's sold yet.

 

i have a 06 4.7 with the same slugish isues on hills have to really get in the the throtttel it only has 51500 miles on it do you think the cat could be stoped up with that few of miles on it if so are ther any cons to just cutting it off an having local muffler guy replace with peic of pipe we do not have emission inspections not sure i could convince him to cut it off for me he has on older trucks iv taken him i could cut it my self its about 3 miles to his shop would that be a problum driving that far with them cut out and wouldnt a light or something come on with the cats not being in ther what would i need to do about that any an all insight would be greatly apreciated

 

Unless all your driving is confined to very short trips with a lot of stop and go, I highly doubt you have a clogged cat with so few miles. I'd be leaning more towards a maintenance issue like a dirty TB, PVC, air filter and/or some sludge in the crankcase...

 

well thanx the maintnece sounds easy enogh once i figuer what exzacly to do but how to tell if sludge is in crank case an what to do about it

 

The O2 sensor has been freed & replaced....took more tools to accomplish than what we had in the garage. The old one was almost completely covered in build-up, covering some of the holes on the top. Am anxious to drive the truck today to see how much improvement I notice. Still have the tapping noise, pretty sure it is the rockers...but that is covered under the extended warranty. Thanks for all the great advice!

 

does the tapping start loud at startup and then quite down or go away? also mostly located at the 8 cyl. (that is the far back pass. side cyl.) that is usally where the rockers start ratteling. there is a redesign rocker and lifter for that year. the rockers will start jumpping off, mostly the back 2 pass cyl. they are not to bad to replace but you need a special tool to do it. you can find them used on ebay for about $100. if one jumps off it does not do damage, just loss of power and will throw a cyl. misfire code.

even if it is your rockers that should not cause a power problem. like others said fuel, air or exhaust. tb and fuel injector cleaning a good place to start.

 

I am extremely frustrated at this point...have replaced the plugs, both O2 sensors...the upstream twice because after the 1st replacement P0420 code came back on & truck would not stay idling, thought it was a defective part. Put 2nd upstream O2 in cleared the code again, drove for 15 minutes and the same code came back, but don't seem to have the idling issue. I had the catalytic & exhaust system checked before I started replacing the sensors, everything was good. What could be causing the code to keep coming back?