Stroker Power Loss

[Jrama]

Hey everyone,

I have a sudden loss of power, feels like I lost 75hp. No check engine (apart from the evap code that is always there). Power loss is more noticeable at higher rpms. No smoke, no noises, runs smoothly, starts no problem, oil is good (No flakes, foam, etc.), no signs of blow by etc. In Neutral it doesn't easily reach the limiter, it wouldn't even go past 4200 at one point ( sounded like it was bouncing off the limiter at 4200). After the full tank (noted Below) It will get to the limiter kinda weakly.

I figured I might have gotten some water in the gas a few weekends ago doing a deep river crossing. The tank finally got down to below a quarter full and I figured it was probably sucking some water. So I added some water remover and put in a full tank, its a bit better but not nearly where it should be power wise (so basically the same).

What are come common things to check out? Engine is a 4.6 stroker probably about 10k miles on it(All same accessory's,manifold,TB,intake etc. as 4.0) 2004 Jeep tj.

To me it might still be a fuel issue? Maybe a clogged cat? Any pointers on what to check is appreciated. I am getting paranoid and thinking maybe the cam lobes are worn/wearing? which wouldn't make sense due to the sudden onset.

Any pointers are greatly appreciated.

Cheers

[KarmaKannon1]

I'd probably start with a compression check. Especially if it seemed to start around the same time I did a deep river crossing.

[Cheromaniac]

Agree. Hopefully no water got into the engine, otherwise there could be a couple of bent connecting rods.
I think a plugged up cat is far more likely though.

[Heck]

Mine was very similar, was a plugged cat.

[KarmaKannon1]

Mine was very similar, was a plugged cat.

It's strange how that seems to happen now and then. I had a buddy who was complaining that his big block all the sudden couldn't tow his trailer on the freeway. They cut the cat off and it drove fine again.

[Heck]

Yeah, at 35k my upper cats disintegrated and plugged the lower. Been catless ever since, 15 years, never thrown a trouble code yet. Almost like VW wasn't the 1st company to fudge on emissions.