Hey everyone. New to site and truck. Just bought a 89 XLT Lariat w/4.9 inline 6 and 5spd with OD. 124000+miles and very straight body. Interior pretty tight with electric everything and it works. Needs a rear seal and some engine TLC but at $150.00 I think I'll live.I replaced all brake parts front and back to include calipers, wheel cylinders, and all lines. Did the brakes myself and had the shop do the lines. Step by step. Now Im going to work on exhaust. Mostly because the cat or cats are rattling and driving me crazy. First question... do I replace both cats or go with an upgrade high flow. Second question... the thing is loping bad at idle. From 1100 to 500 to 1100 to 500... The cats or any ideas. I own a construction Co. and this will be a materials runner. Looking to stay stock or close. Paint and body next week. I could throw a crate in it if needed but I'd like to get another 75000 or so out of her first. I've got before and after pics started and will be posting them as soon as I figure out how to compress them to the limits of the site. Thanks fellas in advance for any input. I'm having a blast tearing down this ol girl.

 

Are the cats themselves rattling, or is it just the heat shields?

 

trust me 200k is nothing for these motor the loping means it could just need a tune up and the throttle body cleaned. check all ur vacum lines too wile ur at it.

heres a link to a pretty cheap replacment cat system it goes from thr manifold to the muffler and does away with 1 cat when i take my truck off the road in a week or 2 im ganna put one of these on
http://www.rockauto.com/catalog/x,ca...,parttype,5808

 

Good thought. I checked the heat shields first. Not loose. the sound is like something rolling around inside. Today is tune up and fluids. I'll keep you informed. i've got the air,crankcase, oil, and fuel filters too. The pcv valve seems to be hiding. the call out in the manual doesn't help but I'll find it I'm sure.

 

There are alot of vacuum lines on this thing. Should I just get a rool of the material and change them all?

 

Hey Rehab, shoot the throttle body where it meets the intake with some carb cleaner/ether/favorite volatile spray. I just replaced the gasket there, and it was giving me similar problems. Apparently that gasket was a problem from the get-go. Good luck, Peace, Dave.

 

if they aint leeking or cracked ur good n the pcv is on the back side of the plentum on the valve cover its one of them things u kinda have to feel for

 

Ok just looked under the ol girl and the oil pan seal is shot. Looks like I can get it out without removing the crossmember. True? Somebody really neglected the mechanicals on this rig. Why own this 20+ year old beauty if your not going to babysit a little?! People suck.

 

Thanks hillbilly I found it. May have to lose a few pounds to get my big a## back there though.

 

Got a can of goof off. I'll do that now. Gasket?

 

on the oil pan ive never done one in the truck b4 but ive herd guys say for the 4.9 ud just have to undo the motor mounts and put 2x4s between the mounts and frame to get enough clearance to get around the pick up tube for the oil pump. again ive never dun this so im not sure if it works or not

 

Yeah, throttle body gasket. There must have been a manufacturing issue with them, because the new gasket is "improved" The old gasket sucks down into the throttle body from the top. Just spray carefully to check for vacuum leakage. You can also check your vac lines for leakage that way, again, just be careful spraying so you don't hit something you didn't want to. If there is a leak, the engine will rev higher. Good Luck, Peace, Dave.

 

That's the impression I'm under, Lost. Peace, Dave.

 

This is going to be a long slow ride.

 

Back. Vacuum lines from the throttle to the canister are trash. Will replace. While gone my buddy came to the conclusion that the diaphragm in the EGR is not opening. Will pull it to test. Picked up a vacuum pump. Dont give up on me yet Flyer. I'm old and learn slow but I do listen and learn. Thanks for the input. I'm using it.