I just got a 96 eagle talon for 500 bucks. Everything the good on the car except cylinder #4. I did a compression test and it was 160, 165, 160, and 5. I put oil down cylinder 4 and the compression went up to 35. I was wondering what exactly is wrong with it. What all do i need to fix to have it running good. what parts do i need to replace. How much do you think its gonna be. do i need to rebuild the whole block or just that one cylinder. thanks in advance.

 

I would do a leak down test in that cylinder and list to where the air is leaking.

 

you need to rebuild the block if you want to run on more than 3 cylinders. You have a blown Piston Ring in that cylinder and the only way to fix it is replace all the rings and bearings in the motor by dropping the crank out

 

So i have to rebuild the whole block i cant just replace that one cylinder. and is that all i need to replace is rings and bearings you don't think i need another piston.

 

Well it depends on how old the pistons are and if they are still within spec. Most likely due to the ring breaking you will need a new piston...in which case you need to replace all 4 (or at least i would suggest doing it.

 

I would do this before fixing anything ^^^

 

Sounds like the first thing you need is a leak down test.
But from your initial results, I'd say you prob need a valve, or a valve seat or two.

Real rough guesses here, market rates differ, etc...
Leakdown test, prob an intial $100 diag fee at dealership?
Getting a complete rebuilt head, if that's it, $400ish (I'd rec full rebuilt head)
R & R ing cyl head, $600ish
Gasket set, $150ish
Usually a dealer will waive the diag fee if you buy the work.

 

^^^I dont understand why you think its a valve from these tests. Did you not see his wet test result. When he put in oil he got 35 more psi! that is not do to the valves. Increase in compression from a wet test is ONLY from piston rings. So i dont see why he should waste money on a leakdown test when it seems very apparent that the rings are his issue

 

Your wet test displays your gain of compression once you added oil into the cylinder. I agree that your rings need to be replaced.

Make sure you check out your cylinder wall and piston ( just to be on the safe side!)

and please replace all four pistons and rings. Its great that you got the car for so cheap with only this problem but there is no telling what other problems can arise.

 

So what you all are suggesting is that i replace all four rings pistons and bearings.