Hi Guys,

Here are my symptoms:

1. The Truck starts but runs a little rough. When she starts up, a loud Jet-like sound comes from the engine until rpms drop back down to idle.
2. Then while driving around town no real issues other than the jet sound. The rpms rarely get up past 2000 due to speed restrictions.
3. When I get on the freeway, she is slow to get up to speed. I can gradually get her to 65 on a level road. But if I mash the gas The engine just get's really loud and speed doesn't change much.
4. If i run into a hill, I'm in deep **** even with a running start at 65. The truck downshifts halfway up the hill and eventually decelerates to 40. Engine is struggling at this point and barly able to maintain 40 mph at 3,000 rpm. It sounds worse when I try to push it to 4000 and I don't go any faster maybe just the same.
5. Once the road levels out and my RPMs are back down all seem fine except the Jet sound.

I have been limping along like this for several months now. Can't afford for the dealership to get involved.

Before this all happened I had a rattle coming from my exhaust. I i solated the rattle to the joint where the cat meets the muffler just under the passenger rear seat of thesupercrew-I removed the u-bolted counter weight? Now the muffler is just loosely connected.

I've bee searchiung though the forum and I suspect 2 possible issues

1. IAC
2. Clogged Cat

So How do I torubleshoot or isolate the problem? Should I be looking at other areas as well?

 

that roaring sound is almost definitely the large cooling fan. Likely the fan clutch and or temp switch is not working correctly. Sounds like you fan clutch is locked all the time, believe it or not those fans can soak up quite a bit of power.

you may have more than one issue, but thats one of them for sure if it roaring all the time.

 

You have a broken up plugged cat.
You cannot keep running the truck like that risking the rest of the motor to burnt exhaust valves , over heating, losing head gaskets and effects of overheating etc.
This is why you have no power. it's bad from your discription.
Can't repair it, park it and save further damage.
Min. cost for one side is about $300 plus possibly new OX sensors and labor for after market parts.
If a dealer get's into the act, expect the cat for one side to cost about $1700 plus labor retail.
One reason is the factory rear cat is bigger and higher quality but after market works fine for the rest of the time you will own it.
It's your call.
Sorry it's a hit on you but it is what it is.
Good luck.

 

Thanks Bluegrass 7

Could this be a DIY repair? I've never replaced a cat or a muffler but I have replaced exhaust headers before on other cars and I've changed 02 sensors before. Also How do I narrow down whic cat converter is givivg me the issue?

Thanks!!!

 

First do you have CEL light on?
If yes what code it present?
My assumption is the side you had noise with is the side causing the blockage.
To change out a cat side, use a torch to cut the head pipe and the rear to the muffler and the crossover over the side you find with the issue.
This is to speed the job and be able to get to the manifold bolts better.
Getting the nuts off without breaking the studs is key to success.
Heat the nuts to a red color to break the bond.
Use a metric socket that fits good and begin to back them off a little till loose.
Spray some loosener on the threads and let set for awhile.
Begin to back off the nuts back and forth going a little more off each time so as not to lock them up with thread crap ahead of them.
Reheat if needed.
You will need a long extension and a deep socket and possibly a U joint to tighten the new pipe in place on the exhaust manifold.
Since there will be three joints to connect, it will be difficult to get them all in place.
The factory pipe clamps may be a problem so look at them after you get things apart.
One caution is to be sure the new rear cat has it's OX senor hole pointed the same as the old pipe and not straight up or some other direction.
The other way to do the job is to cut the cats out of the pipe and have new ones welded in place without leaks.
A muffler shop may do this for you.
Best I can tell you. The rest is just plain work and common sense.
Good luck.

 

No CEL and no Codes

 

If you have no codes, the Cats on one side can still be restricted from core breakup.
The OX sensors are still satisfied the switch ratio is good between the front and the rear or there would be a code 420.
Have you considered the possibility of the muffler coming apart inside or the tail pipe is bent over?
You have to find the cause before any action can be taken to correct the cause of no power.
Good luck.