vac, compression and otuer healthy engine questions

[Turpro]

Ok first let me explain. Car runs great. Idles at 800rpms. Pulls hard still(N/A). Burns about 1 qt of oil every 900-1000 miles. Doesn't smoke on start up. Smokes a little when WOT after 5000rpm(after vics kicks in(holy crap I just sounded like a honda driver lol)). Does have a leak or 2.

When I was boosted the boost/vac gauge read 18-19 on vac. Signs of a healthy bottom end?

What's good compression? Testing this weekend. I think I've read 125-190

If my valve seals are crapped out could that cause that much burning of oil?

If it was burning that much oil and had good vac numbers could I weed out bad rings?

[Ace]

Healthy vacuum is around 20 hg/mg, It's an indication of overall sealing ability really. It's telling you the condition of the rings and the valve seats.
As per the FSM, minimum compression is 128 and healthy is 182 and their shouldn't be more than 28 Psi difference between cylinders. If compression is low, pour a teaspoon of oil in cylinder and recheck.If compression improves, it's the rings/piston/cylinder wall. If compression stays low, it's the valves.
If you've got bad valve seals it will smoke on start up and then stop.
It's hard to say whether it's rings causing your oil burning or not. I guess we'll see what your compression readings are.

[KAinjection]

^^^I guess you beat me while I was taking my time posting.

The valve seals could definitely cause the smoke, and at idle your vacuum should be about 17-22 and the needle should be steady. The other thing you can do when checking vacuum is snap the throttle and make sure it goes to zero and then below the normal idle level like about 25, then return to the normal idle reading. My 95 Escort FSM says the compression should be 164-200psi, and the pressure from the highest to lowest cylinder should be within 75% of each other.
From your vacuum reading your bottom end sounds fine, but do the compression test to confirm it.

[Turpro]

Yea it snapped back to 0 when I touched the throttle then went back to 18-19 never past 20.

But would bad valve seals cause that much burning of oil? I wanted to put valve seals in for a while just to see if it made a difference but I've been lazy. Its not a small job either. Guess I'll do the comp check and see what that comes up with before doing them. If the comp check is good then I will. While I do that I'll clean the HLAs. If the comp check turns out crappy I'll just grab a jy motor

[1st Gen]

I had a problem with my daughters 07 Kia Rio. It started burning oil crazy fast all of the sudden. We didn't realize what was happening before the engine went out. (skip the part where I get them to do the warranty work)

They put a long block in it and it still burned oil at over a quart ever thousand miles. I took it back and after doing an oil burn test, they decided to put another short block in it. After another month of the same symptoms, they put another long block in it.

The last long block took care of the problem but it's clear to me that the problem was never the motor.

I'm sending you a PM with a link in it to a work log. The only really pertinent part for you is the last page. In it, a member suggest the PCV valve might be foobar. He makes a pretty good case for it too.

I never did follow up to find out what the problem was. If it's important, I can take the drive down there to fine out.

Even if the PCV is passing oil, I'd still do the compression check. It's good info to have.

[KAinjection]

^^oh yeah thats right! My escort was actually burning oil and I thought the rings were just getting wore due to the amount of mileage I have, until I discovered that PCV line going to the intake had deteriorated and collapsed, plugging it up. After i replaced the hose, no more oil consumption, although when it was, it never smoked that I saw.

[Escort92man]

first thing I'd do is check your PCV system yeah! cuz your vacuum is OK and PCV can cause a lower vacuum reading cuz you have an internal vacuum leak basically, yeah check PCV and if that doesn't help at all do the compression test etc etc.