Hello,

I'm another noob to the threads so please don't kill me if there's already a similar thread. My truck has a slow oil leak that I haven't yet tracked down. I topped it off with some more oil until I had a weekend where I can try to figure out where the leak is. I noticed immediately after adding oil, the truck lost power while accelerating, and there's now a strange rattling noise that sounds like it's coming from around the intake manifold area. Originally I thought maybe I put too much oil in but that idea was unfounded as there was no evidence of froth before or after removing some of the oil. Even after removing said oil (its between min and max on the stick), the loss of power and tapping remains. I know I've now used three different words to describe the noise but I will post video of my truck, and two other people's trucks all making the same noise. Neither of the other videos seem to have reached a conclusion.

There's is no check engine light nor a code yet, so I have to guess where to start. I plan on trying removing the serpentine belt this weekend to make sure I'm not hearing the fan or one of the pulleys. I'm even thinking of going as far as removing the valve covers, which is something I have never attempted before. I was told by a friend to try looking for an obviously out of place rocker arm, etc. I also tried looking up information regarding the IMRC because another user with an 05 was having the same issue but I think those are 3V 5.4L engines. I cannot seem to find a single video with regards to IMRC and the 2V 5.4L engine, So I was wondering if it even has one and where would it be (you can see the noob coming out). I figured if there's a plastic gear in there turning and it's stripped that might also explain the noise at that RPM and above, and the loss of power if the runners are stuck. These are all, of course, my guesses as I have no real experience beyond changing my brakes, both front Hub and bearing units, and my spark plugs. I've never messed with anything in the manifold or under the valve covers. I'm not sure if a spark plug that came loose would make such a noise but I changed them out myself (first time) back in August or September of 2020 (I found the driver side to be extremely tedious).

With that being said here are the videos starting with my own:




Sorry if my responses are delayed, as I'm currently at work and plan on beginning breaking down the suspected areas starting shortly after I get home. I will keep checking the thread until then though. Thanks ahead of time for any ideas anyone may have.

 

The noise in the first video sounds like a problem with one of the accessories at the front of the engine - fan clutch, alternator, etc. Pull the serp belt and fire it up, see if the noise is still there.

Loss of power can be blocked cats, take it to a muffler shop to have them checked.

 

Yeah, I think that's gonna end up being the first thing I try because it's the easiest.

 

I think I would remove the throttle body and inspect it. Loss of power and a rattling noise in that area makes it a suspect in my opinion. Just wild guessing.

 

Welp, I've removed the serpentine belt completely and the noise persists. Moving on to the throttle body.

 

For the noise check around the ngine compartment, something could be loose. I had a motor lift bracket rttling on mine only to find out the bracket had broken from vibration fatigue.

As for the loss of power, run a vacuum gage test. It can tell you a lot about what's happening with your engine including if you have a blocked exhaust.

It's an easy diagnostic test that only takes minutes.

 

I ended up having bad front cats. The guy at the muffler shop said (and showed) the rear ones are ok but they're old and that I could start with just the front cats. The performance issue persisted and a new hissing noise was introduced. I asked them to check the welding immediately after leaving, because you can hear the abnormal hissing while driving. One of the guys said it's coming from the exhaust manifold on the passenger side (it's not). The next day I went back again because I could smell emissions from near where the front driver side cat was welded on and that is also where the hissing is coming from. Again they swore it was the passenger side exhaust manifold. A different shop that was diagnosing the motor found back pressure from the exhaust still, and also said the hissing is coming from behind the rear cat. At that point I was just frustrated with the whole issue and moved my brats car seats to a different car. The muffler shop I went to didn't do pressure tests because they drill a hole and use cameras to see. They must not have done so behind the rear cat because the issue persists.

I've been using a different car for now but plan on trying to pull apart the exhaust near the y pipe to see if the back pressure is relieved. That way I can figure out if the rear cats are also bad or if the issue is closer to the muffler.

Long story short, nothing has been resolved, I've poured in the amount to replace 2 out of 4 cats, and a new hissing noise has emerged.