Running very rough when put into 'drive'
Lead Driver
Joined: Aug 2003
Posts: 7,592
Likes: 10
From: **** hole San Jose ca.
If it's starting to use a lot of oil then, I'd go a long with bad intake manifold gaskets.
A common problem on high mileage engines or the intake was not Torqued enough when installed. And if a engine has had the heads shaved.
And if they been shaved any more then .020ths the intake needs to also be milled enough square up the gasket gap to hold the even pressure on the gaskets. Or they will leak closest to the exh. intake cross over port most the time.
Orich
A common problem on high mileage engines or the intake was not Torqued enough when installed. And if a engine has had the heads shaved.
And if they been shaved any more then .020ths the intake needs to also be milled enough square up the gasket gap to hold the even pressure on the gaskets. Or they will leak closest to the exh. intake cross over port most the time.
Orich
Senior User
Joined: Nov 2012
Posts: 128
Likes: 0
From: Foresthill, CA
Normally an intake that is not sealed properly will leak oil out of the ends onto the engine block on either end, not into the cylinders. It will create a vacuum leak into the cylinders causing a high idle situation. Provided there are no internal engine problems it sounds like your pcv system has a problem as JEFFFAFA stated. The pcv system is normally plumbed in the rear of the intake so if it is sucking excess amounts of oil it may dump it into the rear cylinders. The engine dieing when you hit that dip may have just been a coincidence of the plugs getting fouled from the oil.
Lead Driver
Joined: Aug 2003
Posts: 7,592
Likes: 10
From: **** hole San Jose ca.
When a FE block has a internal vacuum from the intake gasket leaking they don't leak oil out the ends at the oil return holes. But at the inner areas of the intake & exh. ports runners. This won't show up on a vacuum gauge per-say as it's very slight pulling oil into the intake port runner. This oily cylinder will show a very good high compression with oil fouled plug that seals the rings that can be misleading, to guys who have not had much engine problem experiences of trouble shooting.
But also the FE engine heads are known for bad valve guilds an their upper stem seals getting hard and cracking falling a part with sometimes plugging up the head oil port return holes This also can fill the valve cover up to the level to the valve guilds that sucks oil down through them.
Careful inspection while pulling the engine a part and you'll find all the tell tail signs of what failed on an engine. So keep your eyes open any possible area as listed.
Orich
But also the FE engine heads are known for bad valve guilds an their upper stem seals getting hard and cracking falling a part with sometimes plugging up the head oil port return holes This also can fill the valve cover up to the level to the valve guilds that sucks oil down through them.
Careful inspection while pulling the engine a part and you'll find all the tell tail signs of what failed on an engine. So keep your eyes open any possible area as listed.
Orich
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