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1985 Merkur XR4 - can a vacuum leak affect oil use?

Boost and vacuum leak that seems to cause an oil leak/loss of oil. Just rebuilt the engine, new T5 transmission and new turbo, is it possible for a massive vacuum leak to cause oil loss or consumption? Car is a 1985 Merkur XR4Ti, sadly you don’t have any options to select that make/model (can you add my XR4?) Would love to have this car running smoothly.

Have you fixed the vacuum leaks? Don’t drive it until you do.

Anything is possible but if there is a massive vacuum leak the engine will not idle or generate any boost. Check the PCV valve as a faulty valve can cause external leaks or oil use in the upper end.

Before wading any deeper into this maybe a good idea would be to connect a vacuum gauge and check the vacuum reading at idle. It should be in the 20" range and the needle should be rock steady.
If not, then maybe both a dry and wet compression test needs to be performed just in case a ring problem has gone haywire.

You won’t get Tom and Ray here; just a bunch of people willing to help in some way.

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Boost/vacuum gauges showed 5-10mm Hg idle, vehicle got up to 0psi and that was it under throttle for the few seconds I drove it with the issue (was 1000ft from work and 10 minutes to get to work before I was late, didn’t feel like calling a tow until later). Checking more systems for issues, may just replace the entire PCV system and breather just to be 100% since I have spares (Merkur aka bring spares with you). Doubt a ring issue, freshly built bottom end and top end, unless more points to that, given this car’s history of odd vacuum issues, I am thinking that until all else fails.

Thanks all!

There’s either a massive intake leak or the camshaft is a mile out of time. Those engines are pretty simple and there’s not a lot of leak possibilities. EGR stuck open?

Are you certain that the ignition timing is correct?

You arent really explaining your issue very well here… just asking a theoretical question. What exactly is going on? What led you to know there is a problem? What was the vehicle doing? Not doing? Etc.

I’m afraid we are well in the dark without giving us some actual relevant details rather than a theoretical question about vacuum and oil consumption. There is nothing to go on here… sorry.

There is a lot left for the imagination @Honda_Blackbird. But I’ll add that a restricted exhaust, most likely a catalytic converter, could also be part of the problem. And a massive loss of oil on that engine is likely at the turbo.

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