I have had my 4runner for over a decade and it runs great. Its a 1990 3vze 4wd 4runner with 252,000 miles, I have always done all of my own work and maintenance on it so that I know its done right; plus I have access to a full shop for any issues. During the last 3 months my fuel damper on the fuel rail went out under the plenum. During the replacement the plastic nipples on the BVSV (bi-metallic service valve) broke that connect to the charcoal canister. I replaced the BVSV and everything is back to normal. There is no more gas smell from the leaky fuel damper however every once in a while I smell oil burning in my cab, if I switch the vent to internal you can't smell it. When I park after driving it you can sometimes smell it outside the vehicle next to the driver side wheel well but not on the passenger side. I have checked the block and under the engine along with everywhere around the engine compartment and can't find any leaks, but in one 2,500 mile cycle I burned 1 quart of oil. I also taped and numbered all of the hoses when I pulled the plenum and was sure I put them back correctly but I could be wrong.

-Could the BVSV be bad or the charcoal canister gone out?
I haven't used a mirror to look under the back of the plenum yet. But also noticed now if my truck is running and I pull the dip stick it starts idling very hard and when I put the dip stick back in it goes away.

-Could one of my vacuum hoses be plugged in wrong? I only have my Chilton that doesn't have any vacuum diagrams. Can someone post a link for the correct vacuum diagrams I'm having a tough time finding them.

 

the rough engine is most likely a vacuum leak.

now about the oil, is there any blue smoke coming out from the exaust? if there is it could be a bad valve cover gasket, or valve guide seals etc.

 

When I was changing the hoses two lines were old tough and brittle so I changed the lines out with new ones. But I will check the lines again, is there any easy way to find a leak if you cant hear a hissing?

There is no colored smoke coming from my exhaust. That can also be a worn piston ring right?

I was also told to check my PCV valve because they can go bad. Would that effect the engine burning the oil vapors?

 

This thread has good info on the hoses on the passenger side of the plenum.
https://www.yotatech.com/forums/f116...e-help-209069/

 

Hey guys, I found this thread by searching for "dip stick idling".

I'm basically having the reverse problem that regnar11b described: when I pull the dipstick out, the engine sinks down to a calmer, quieter idle, and as soon as I put it back in, it revs up again to an unhealthy level.

The check engine light just came on last night, and I haven't run a diagnostic yet. I just replaced the TPS and the cold start injector so I'm wondering "WHAT NOW?"

-Sage