How's the cat? If it was mentioned, I apologize as I just scanned the replies quickly.

Btw, I put the Hughes kit in over a decade ago. Never had a problem.

 

Yeah, I did the hughes kit more than 6 years ago. It is still squeaky clean inside.

 

Didn't you just get your V10 heyyou? Do you still have your old 5.9?

 

I bought the 98 back in February, still have the 96. It's sitting out beside the barn.

 

I did some basic investigation by taking the air hat off and looking down into the intake. There was oil but it didn't look to me like major pooling or anything, just a think later across it and I'm unsure if there should or shouldn't be oil in general or how much is too much. So I went ahead and pulled sparkplug 8 like plenum forum says and it didn't look fouled and black, looked pretty good for the mileage on it in fact. Then I noticed a small puddle had formed under truck since driving yesterday, first time id looked for or noticed it. It appears either my front seal around he harmonic is leaking or the seal between the timing case and oil pan, but since the oil residue extends up to the harmonic, I'm betting om that seal, especially since we did have to replace it when rebuilding engine, and there are no other leak signs anywhere else on oil pan. I will attach pictures in following post after I shower off!

 

Here are the photos of said sparkplug and the front/bottom of pan

 

Anyways, does this sorta rule out the plenum for my explained power loss? Idk what else it could be :/

 

Some oil in the intake isn't a surprise, gets in via the PCV system. That, and it likes to pool at the back of the intake...... That said, on my 96, I did the plenum in that about six years ago, put in a mopar PCV valve, and there is NO oil in my intake.....

 

You have a yellow pan? Weird. Yeah, it's the front seal but doesn't look that bad. Kinda dry even. Mine's nice a wet!

An oil leak wouldn't cause power loss. The plenum should be wet with oil vapor from PCV valve, but you don't want gobs in there.

How's the cat?

 

Yeah the pan was painted along with valve covers, its a black/yellow/silver engine :P Yeah as you can see there wasn't any carbon build up on the spark plug that usually fouls, and the intake didn't seem to have anymore than a thin layer of oil in it, likely from PCV like was said. I think its likely that front seal is leaking at a decent rate which is why i'm losing oil so rapidly, in the area of 1qt 600-800 miles I believe, I've basically had to fill a quart +/- 1/4th or so per month ish.

Im assuming the cat is fine, I recently replaced both 02's and they haven't gone out yet. I think it is possible i'm running slightly rich because I can see some carbon build at the end of my tailpipe (which is right after the cat lol).

I had my dad drive my truck to the store and home from work, and he says it feels like the throttle cable is severely stretched, and the reason it feels different power wise is i'm losing a good two inches of movement in my pedal, so WOT isn't actually WOT, so it feels slower now vs previous for same pedal push. It would make sense since the cable has never been replaced and has been through two engines and such. I always knew you had to push the pedal a bit before cable caught, but I think it was still able to fully open the butterfly in the throttle body. So that's what I'll check for when it cools off. If the pedal is fully opening the butterfly then Idk where to look next.

I'm not sure what could make the power feel so different to me, at times it feels okay, and other times it is really really sluggish, like its being over-fueled and just wont raise rpm. But I know I shouldn't be having trouble pulling to 4.5k with a tune on, because it used to fine, and now it starts to really struggle past 3.5k. IDK