Town Car Troubles

[Chuck Norris]

The TC hasn't been my best friend this week. She is starting to smoke a bit on start-up. I am told this could be bad piston or cylinder rings (same thing I guess?) She has also had some putrid smelling exhaust (smelled like tire fire + sulphur) and has bucked or backfired a couple times. Sometimes she is squeling on startup but the belt seems tight and in good condition. Please tell me what you feel the problem(s) could be. I suspect the squeal is either the water pump or a belt tensioner, but usually waterpump squeal is SOOOO loud and this isn't very loud at all. The smoke is white, but I don't suspect the oft-blamed head gasket as I use no water and my oil isn't milky looking. Still, all and any ideas appreciated.

On a side note, my rear brakes also need replacing, which I would have done but I didn't have the right torx crap. STUPID TORX!!! And plus it got dark so early. :animalmother: :violin:

[Johnnyiroc]

I think your smoke issue could be the good old early panther valve seal problem. It is very common. Do you get any codes or the engine light on?

[Chuck Norris]

I think your smoke issue could be the good old early panther valve seal problem. It is very common. Do you get any codes or the engine light on?

Nope. Valve seal sounds like a better problem to have than bad piston rings. That would require a valve job? New seals?

[LtMercDaddy]

pretty much, the timing chains would need to be removed, along with the cams i believe. the 4.6L if im correct the cam actually rides on the base of the valvestem (no rocker arms). although i could be wrong. after the cams are removed, the cylinders would have to be pressurized if the heads are still on the vehicle so that way u can compress the valve springs and remove the retainers and not have the valves drop in the cylinder, after which u can then remove the springs and try to get the seals off... im sure its a PITA with the heads being attached to the block...

You say the smoke is white tho right, usually white smoke is associated with coolant, oil likes to give off a bluish colored smoke.....

[gadget73]

Hard to say what the noise up front is. I would remove the belt and spin each pully and feel for roughness. Could be a bad belt, tensioner, alternator bearing, water pump, or whatever else is up there.

I'm with those guys on the smoke probably being valve seals. Unless it gets to the point of having substantial oil consumption and starts smoking more or less steady, I'd say ignore the puff on startup.

Might also want to clean the EGR valve and MAF. Apparently the egr gets clogged up on the early aluminum intake and can cause hitching and bucking problems. Dirty MAF just generally causes poor running. The vacuum hoses on the PCV valve have also been cited as a problem area, so make sure those arent rotted and cracked.

[p71towny]

Its the seals, not much you can do except check your oil level. The stinking exhaust is your cats going south. If you don't have emmisions you can punch em. Or you can shell out a couple hundred for some new ones. You might need O2 eliminators if you punch your cats. If your idler pulley and tensioner have never been replaced I suggest those as its cheap and easy PM.

[Dereck]

Hi MissinVicin

No need to pull the front end covers or the cams when replacing the valve seals, you can leave it all in place.

Most of what you wanted to know about replacing the valve seals

Regards

Dereck

[Chuck Norris]

Awesome responses guys! I talked to a co-worker who said he had a similar problem with an older Monte Carlo (the smoke) and he ignored it and regularly checked his oil level. He drove the car like that for a long time but then sold it to a family member who tried to fix it but wound up destroying the engine. I beleive I may just let sleeping dogs lie until I have additional reasons to crack open the engine. I agree that the cats may have taken a crap on me. How do you "punch them out" or remove them? If they are punched do you still need to delete the O2 sensors? How would it affect the vehicle's running condition? Many thanks!

[gadget73]

You shouldn't have rear oxygen sensors, thats an OBD 2 thing. They only check to see if the cats are working anyway. You wouldn't mess with the sensors on your car. You can knock them out with a pipe and a hammer. I'm sure someone on here who has actually done it can advise better.

[p71towny]

It takes a while but you have to unbolt the exhaust from the manifolds,(make sure to let some pb blaster soak the nuts for a couple days its fine if drive it) then unbolt the exhaust where it bolts to the back of the cats. You will need new bolts here and you might need to grind and punch the old bolts out. Once that part of the exhaust is removed you will need a long bar or rod and a hammer. Punch away and shake the old shit out. If you need anything else lemme know.

[91 LTD]

Not that I gutted mine (replaced them instead), but in my research read that a shopvac will get out the crap from inside the cats that could end up in your muffler. I think I read cats go bad after 60k or so? When theyre bad it seems like youve got a trunkful of cinder blocks, mpg sucks, and getting over 60mph takes forever.

[Chuck Norris]

Mine takes about 13 seconds to break 60 mph, idles a little rough at times, and the exhaust ranged from normal to sulphur to tire fire. I will probably replace mine with some hi-flo cats. I'd prefer to be legal. And who knows, they could pick up emission testing here. As a side point, I'll probably wait until I can get some long-tube headers and dual the exhaust if I can get money set aside quick. Oh who am I kidding. I'd settle for a flowmaster muffler.

[gadget73]

Put duals on it if you're gonna mess with the exhaust. Stock single exhaust is crap.

[p71towny]

Headers are damn near impossible for a 4.6 panther. I might look into some for the towncar when I swap engines. Just go with high flow cats and dual exhaust from a junkyard. Throw some quiet flowmasters on and enjoy the gas milage and sound.