Various engine problems, I'm clueless

[Ex-User (107751)]

Decided to open a new thread, got lost in the last one.
Bought a ph2 172 about 2 weeks ago.
Noticed the following problems -
1 145-150PSI compression across all 4 cylinders.
2 3-6% leak-down across all cylinders.
3 Gets 25 mpg (uk gallons), 95% normal city driving. at 65mph the computer shows 40mpg or better (found a thread 4 suggesting this test).
4 Poor idle. You can't see it through the RPM needle, but you can hear it in the video.
5 Lost about 5mm of antifreeze level in about a week and 200 miles.
6 2 minutes after starting up from cold (even 1 hour after a long drive), exhaust starts blowing white smoke. Revving to 2000-2500 rpm makes the smoke much worse, but no smoke after 3500rpm. Keeps smoking until the engine is fully warm. You can see how it smokes in the video, but it smoked 10 times worse in reality when it had a free-flow exhaust.
7 Very strong exhaust smell, maybe just the decat.

Nothing weird on oil cap\oil stick, no fault codes except "p0141 bank 1 sensor 2" (Second lambda).
Here's the video : https://vid.me/i916
btw is the popping sound at 3:20 normal ? also is the engine sound normal for a decat ? sounds rusty.

Most of the problems point to a timing problems. But I want to sort out the smoking first. There are no trusty professionals in my area, so I want to figure out what's wrong before I go for random costly fixes, as I'm tight on budget.
Thanks !

 

[Mar172]

You might be better off replacing the engine

 

[Rob669]

Hells Bells this doesn't stack up! You say that you're clueless, but you have done a complicated compression and draw down test. As far as I can tell you've got a small coolant leak and a perhaps a broken cat so go and get the emissions tested at a garage. How exactly can an engine sound rusty? It might help if you tell us where you are based, is it the UK?

 

[Ex-User (107751)]

It has a decat... I don't know how to describe the engine sound but you can hear it in the video. I wish this was my concern though. :smile:
I'm far from the UK, there are no specialists for these cars here

 

[Rob669]

I can only hear the exhaust and it looks quite corroded so will need replacing. If you're in Malta then there's no need for a cat as no one really bothers, but in most other places in the EU you are going to need one. Do you know if it was properly maintained before you bought it, have the belts been changed and decent oil used, type d coolant etc? These cars can start to lose coolant due to the hoses becoming hard due to age (so the clips become harder to attach tight enough to completely stop leaks), they can leak from the radiator especially where the plastic body on the fan vibrates (if you remove the radiator you'll see where it might have rubbed enough to cause a small leak).

 

[Ex-User (107751)]

Not sure how well it was maintained unfortunately... couldn't be very picky though, the car is really rare here.
Could this type of smoking be normal ?

 

[Rob669]

No, smoking isn't normal.

 

[Ex-User (107751)]

Will driving with wrong timing that leads to these symptoms (except the smoke), cause any damage over time?
I don't want to take it to a mechanic before solving the smoking issue, as it's very pricey.

 

[Ex-User (107751)]

The metallic noise was the emptied cat, replaced it with a pipe and it's gone.
Any idea about the rest of the problems ?