I posted something about this a few months ago but I have a little more info that may clue someone in...
My truck had an exhaust leak so I took it in. They replaced the forward most pipe that hooked to the exhaust manifold. That didn't work - they said the exhaust manifold needed replaced. I took it to someone else who took off the manifold and had it machined. They put it back on and it was quiet again. But... That fix caused another problem. The truck idles rough and hesitates when I take off. It seems to run smoothly once I get some speed going. I took it back to the shop and they replaced the plugs, the fuel filter, and did a valve adjustment. It helped very little. Few key notes:
- It never ran like this before. Always ran smoothly. Didn't start this until I sealed up the exhaust.
- My father suggested putting rubbing alcohol in the gas tank, maybe it had water in it. It didn't like the sound of it but did it anyway. That did fix the problem but only if I keep alcohol in the gas. Once it runs out, the problem comes back.
- The check engine light comes on occasionally, always has
- The shop that fixed the manifold said the exhaust has been leaking for some time
I figure it could only be one of two things: I need to replace the O2 sensor/s or maybe the CAT
Any ideas? Please help. I want my truck to run like a top again.
Thanks Mike