TURBHOE

iTrader: (4)

What can cause an engine to (exhaust) smoke when engine breaking but go away during normal driving/ acceleration? I wasn't sure where to post this so if need be move it. It's my wires little gas sipper. I put new rings in the motor but when she down shifts or just let's off the gas for a few moments it smokes. But once she takes off again it slowly goes away until it's not there at all.

1Bear

iTrader: (1)

I would imagine that it is oil being sucked into the cylinders, as when the motor is still turning at a decent clip and the throttle is closed, the vacuum goes way up and can possibly suck in oil past the rings, worn valve-guides/seals, pcv and so on. The issue now would be finding out where it’s coming from.

nonnieselman

iTrader: (10)

Id have to guess the valve seals.. Like 1bear said, there is alot of vacuum when your engine breaking.

Sc00by

I agree......I would say if the rings are new start looking into some new valve seals. Does it smoke a little on a cold startup?

TURBHOE

iTrader: (4)

I'll have to look next time she starts it. I put a gasket kit in it but not valve seals. It was bit of a generic kit too. Just to get it going so I can build the new motor with turbo later on. I wonder if the Pcv is bad in it. I replaced mine but not hers. Being that I didn't see any smoke at high rpm like it did before I assume the rings sealed good. I did a good hard break in on the rings after I finally got it all together. Never thought of valve seals and it's a high mileage motor.