hello, i have a 1994 ford ranger with the 4cyl. My prbem is that it uses 1-2 quarts of oil every couple of days and i can not find a oil leak. I have pressure washed the whole underside of the truck and degreased the engine and i can not find a oil leak. It dose not smoke all the time but every now and then there will be a little puff of smoke out the exhaust and then every now and then every now and then (only when i stop) it will come a huge cloud of smoke but when it dose it i cant ever tell where it comes from. But the truck runs fine and dosnt miss or anything

 

If you ever see a puff of smoke out the back, that is not normal. I'd say you have an internal engine problem.

 

I agree but it isnt all the time that it smokes all the time. And the engine runs to good to have internal problems. I drive it everyday and it dosnt skip a beat

 

You may want to check valve stem seals. The engine vacuum may be sucking oil past the seals and still the engine may run well.

 

pull your spark plugs and see which one is oiled gunked up then check the compression on that cylinder either a valve seal has gone bad or you have a broken ring on piston,,, if it was an earlier 2.3 i would suspect the number one cylinder they had manual fuel pumps and were notorious for going bad and spraying raw gas on the crank and cylinder causeing broken rings and spun bearings on cranks. the only other thing i can think of is head gasket gone bad and letting oil be sucked in to clyinder, but most times when that happens you have oil in radiator and water in oil.....but it could be possible for just the oil to leak by.

 

Had a 1990 that had the same problem. It was the valve guide seals that were totally toast. Mine actually sprayed oil residue out the tailpipe onto the building I parked next to. Run your finger around the inside edge of the tailpipe for oil residue.

russ

 

Well, if it is not leaking out, then it is getting burned. Unless you have oil gremlins that steal it overnight....
An engine can be burning oil and not leave a blue cloud behind when you drive it. Blue smoke indicates you are burning a LOT of oil. My Dad told me that, and he was an engineer on the B-29 and B-36 engines & B-52 turbines. The limiting factor for distance back then was oil consumption.
Good suggestions to pull the spark plugs for inspection. I'd bet you will find them all a little oily and carboned up. You can change the valve stem seals without removing the head if you want. Use a piece of rope fed into the spark plug hole and rotate the piston up to hold the valves in place while you remove and replace the seals.
I would be looking at the PCV valve and oil separator. The PCV is 'in line' underneath the intake manifold. The separator is crammed into the side of the block, kind of a 'flattened can' looking thing with the PCV hose attached. The PCV could be pressurizing your crankcase, or the separator could need to be cleaned. Inside the separator is a labyrinth of metal, either very coarse steel wool looking stuff, or a physical labyrinth that makes the vapors 'take the long way' and cause droplets of oil to touch the walls or wool, and condense and drain back into the crankcase. In most cases the plugged separator or gummed PCV happen to engines that have not been maintained very well, and get sludged up.
The valve stem seals can go from age or heat. They can get brittle and fall to pieces.
The 2.3 will run a long time with regular oil changes.
tom

 

Hey, Tom! I never heard of that rope trick before, but it sounds like a great idea!

Regarding the "not smoking all the time" mystery. The smoke might be getting consumed by the catalytic converter. And burning oil in the catalytic converter is ruining it, too. Oil burning engines can run just fine, up until they they reach the point that they burn so much that it starts fouling the spark plugs.