Oil mysteriously disapearing!

[kimcrwbr1]

Either that or if it is pulling too much vacuum if you put your cheek up to the breather tube there should be a slight vacuum at an idle you can`t feel with your finger. if it is not pulling fresh filtered air in with new pcv then it is not keeping up with the blowby. I always change the pcv with my yearly spring tuneup air filter, breather filter, cap and rotor and do the plugs every other year thats the schedule I keep. The pcv will pay for itself in mpg with a few tanks maybe less.

 

[BRUTUS_T_HOG]

i fully agree man. even though i sprayed it clean, i am replacing it tomorrow. i did a little test, if you unhook the vacuum hose from the top of the PCV valve, the truck dies because of such a massive vacuum leak...but with the valve in, it doesn't die...and the valve is not opening under the vacuum...which would say to me "it's stuck closed". so yea, i think that's my issue. so to the original poster...check your PCV valve!

the pcv is supposed to be "stuck" closed at idle, and fully open at WOT. engine vacuum holds it shut because at an idle there is not as much blow by as there is under full load.

 

[kimcrwbr1]

The PCV is a three dollar item change it then there is no question how it works.

 

[LowStandard]

yea, i'm replacing it...as i originally said...but now hearing this makes me wonder if it's even gonna work. we'll see...

 

[LowStandard]

ok, update time. the PCV valve didn't do crap. the old one looked fine and, come on, you can look at it and pretty much see every part of it. not some black magic in there. if i sound kinda mad...well, i am. i just made a 1149 mile trip and used 9 quarts of oil. every fuel stop and a few in between i had to stop and add a quart and a half or so. this is just retarded. the damn thing doesn't smoke...ever. it doesn't leak...at all. the plugs all read clean. i'm beginning to think the head might be cracked over an oil galley and that's how the oil is continually getting in the TB with no other signs of a worn-out engine...ideas...? anyone?

 

[BRUTUS_T_HOG]

pretty much the ONLY way it can get into the throttle body of a good running engine is from a bad PCV system. do you have a clogged PCV breather? hose? collapsed vacuum line? how much vacuum is at the PCV hose where the valve goes?

 

[LowStandard]

i'll have to try to get a vacuum measurement at the PCV vacuum hose...but its so much the truck dies if you unhook the vacuum hose from the PCV valve. as for the hose being clogged...i don't know...i'll have to check. it's definitely RPM related...keep the RPMs low, no oil usage. RPMs go up, oil gets slurped down. the truck runs great. still have yet to see smoke. also has decent power. really confusing. going to run a compression test on it next

 

[Bryan22]

9 quarts in 1200 miles is not going to be a simple fix. time to tear the motor down or swap it out for another one. that's just outrageous. also it's probably not smoking because the cat is working... for now. i got a used motor and trans for my truck for 350 bux about 2 years ago and it's still purring away like a sewing machine. If i wre in your shoes i'd be looking for a cheap used motor with good compression. good luck.

 

[LowStandard]

yea, i'm actually thinking along those same lines...