I need help bad please

[getthingsdone]

I have a 2000 toyota corolla, with 1.8 16 valve. 105,000 miles, manual trans..just bought this veh. says misfire cylinder 4. So here is what I have done.

I started trouble shooting. swapping coils from cylinder 4 to other cylinders to see if the code follows after clearing it. No, stayed at 4..
so i moved on to the fuel injector. I did the same thing to see if it followed.. no stayed at cylinder 4. I changed the plugs, stilll misfire..
I did a compression check, I have 170 on 1,2,3, and on cylinder 4 I have 0. Yep, none...

I have some black smoke when the car is under load, as in acceleration, shaking and constant miss. lack of power... Trying to determine wether it is the rings or valves or what.. I took valve cover off and checked for broken spring, and they all seem ok. No oil in my coolant or vise versa. pleaze help...

[getthingsdone]

ps I just did a wet test, and it raised the cylinder compression to 40 psi. from 0.. which would still mean valves correct? if it was rings it owuld of shot up closer to normal range or at least 80-100psi... correct me if im wrong though.

[quick69gto]

Typical for that generation of Corollas.
It sounds like the engine fell victim to the "oil sludge problem". With my experience it's usually #4 that fails with either no compression (rings) or it will spin the rod bearing.
I maintain a fleet of 35 or so 1998-2002 Corollas and I have had to replace the engine in over half of them because of the same exact problem.
In the past, I usually replace the engine with a compression tested, low mileage, used engine but I have found that the replacement engine eventually shows the same problems.
In the future, I am going to attempt to put an '03 and above engine (long block) into the '98-'02 generation Corolla. If I use the original intake and exhaust manifolds (98-02) on the newer block (03+), I believe it will work. We will see.
We now look for the '03 and above generation Corolla when we need a replacement vehicle.
By the way, I usually get 130-150psi compression out of a good running '98-'02 Corolla.
Just my experience.
Good luck!