so....'98 dodge ram 1500 5.2L
230k on it, bought it with 200k 5+ years ago....not sure of its prior maintenance.

check engine lights been on for quite awhile. forget the exact code, but it's a catalytic converter sensor. and it doesn't come on when it's really cold outside (say, below ~15 degrees F). have still passed emissions (twice).

over the past 6 months i've been burning/leaking a lot of oil. probably over a quart per 1000 miles.

gas mileage has also been pretty darn bad. around 10mpg, mostly city. however the last long road trip i did (500+ highway miles) i still got ~16.

truck has always seemed pretty weak to me in terms of acceleration & maintaining speed up hills, but i don't have much to compare it to. doesn't go over 85mph on a flat stretch.

definitely can hear it pinging under ~1200rpms under load, or under more load on an extended hill at higher rpms. 87 octane

first attached picture is looking down in to the top of the throttle body (took air filter/butterflies off)

second attached picture is up from the bottom where i'm dripping oil.

thoughts on this being the plenum gasket?
is there a better way to check? (i read the vacuum test is also unreliable)
if i go for it....what else within reason should i do while everything's apart?
how long do you think this should take an amateur mechanic? i did the head gasket on a toyota 22-re twice this winter...but have never worked on this engine before.
any guesses on that leak at the bottom?

thanks!

(edit....crap....mods might want to merge this with the giant plenum thread. sorry)

 

Yep, you've got a blown plenum. I assume you've read the plenum thread already, so you should know that you might as well do the timing set, water pump, cap and rotor while you're in there.

As for your leak on behind the crank, that looks like a crank seal went out, but it could be something else.

 

that leak looks like its the oil pan gasket at the front lip where it sits around the crank. id try replacing the oil pan gasket with a fel-pro(which you should always get when it comes to gaskets) and the other problems do indicate the plenum, just cuz you dont have alot of oil pooling dont mean that its not fouling up your o2 sensor and things along the way. timing chaing makes a night and day difference, and yes its best to change the timing chain and pump together. but its not req. to just get the plenum done. but i would recommend replacing the O2 sensor with a NGK when you do the plenum

 

Do the plenum.

Recommended: plugs (copper), wires, cap, rotor (brass terminal), aluminum plenum plate (Hughes or Ebay).

Needed: intake gasket set (Felpro), bypass hose. If using the stock metal plenum plate, cut the bolts down a touch.


As for the leak, it appears to be the crank seal.

Recommended: timing chain and gears, timing cover gasket kit, water pump.

Needed: timing cover gasket kit

I may have forgot something off hand.

 

ahh yea after lookin at that pic again, yes its the crank seal thats in the timiing cover. sense you got the 5.2 you wont have a harmonic balncer to pull, so thats a plus, just unbolt the pulley and take the cover off. but yes replace with gaskets AND use some added RTV for good measure on the timing cover and the water pump for sure!

 

He still has a 'balancer', it just isn't really balancing anything. The 'correct' term for it is 'harmonic dampener'..... as that is it's purpose. Some are also used to balance the rotating assembly, but, not on the 5.2. Still need the puller to get it off.

 

The FelPro timing cover set that I got came with a crank seal and a speedie-sleeve.

 

so the 'specialty' stuff i'll need is a...
-36mm fan wrench
-harmonic balance puller
-1 1/4 socket
-lb/inch torque wrench
-and i'm reading an air gun would help speed things up as well

parts...
-hughes kit (includes new bolts, intake mani gaskets, bypass hose)
-wires (just did plugs recently)
-cap
-rotor
-water pump
-thermostat
-timing chain cover gasket + crank seal gasket
-timing chain + gears
-pre-cat o2 sensor
-throttle body gasket

+ black rtv + basic fluids/oil change.

is there a good writeup/pictures for getting the timing right? if both sprockets are keyed, can you not just remove and reinstall new gears/chain as long as nothing moves relative to each other?

i read through this one...
http://www.pavementsucks.com/tech-article-37.html

but a lot of the pictures are out of order, and the part regarding the cam timing is beyond confusing...
also curious about the cat...
is it likely i need to replace it at this point?

and in regards to testing that....when people say take out the upstream O2 sensor to see if the truck feels more powerful...etc, does that mean just unplug it, or leave it plugged in but unscrew it completely and let it hang so it's getting fresh air?

thanks!

 

You can test it before you start repairs.... Just get a pressure gauge, drill a small hole in front of the cat, stick the gauge in there, and start the engine. If it's over about 2 PSI at idle, cat is on its way out.

 

will do.

i guess the timing is pretty simple. with (almost) everything apart....turn the crank until marks/dots line up, uninstall....re-install.

next question....

my ventilation fan inside the truck has never had any variation. it's either full blast...or nothing. any suggestions as the best way to problem solve this? where's the fan motor located? or is it more likely the switch in the dash is out? either way a shove in the right direction would be helpful, before i start mindlessly taking stuff apart.

thanks again