This is the weird thing we turned car over and got 80psi, next attempt 30 then nothing. I removed rockers completely and tried and got 30psi, lubed and hit valves with rubber mallet then got 40. I repleted process again and got 50psi then on third attempt 0 again. Does this sound like sticking valve? I am wondering if it might be bent. I am trying to avoid pulling head but I think I will have to. I looked at lifters and they appear normal.
If you're trying to keep it on the cheap here, I would try this. Pull both rockers and charge that bad cylinder up with compressed air to see where the escaping air sound is coming from. Listen in the intake plenum/throttle body.. nearest exhaust outlet.. and finally the crankcase oil returns in the head(may be better sound isolation to mock reinstall the valvecover and listen to the oil filler tube/hole). Listen for an obvious "tinny sounding" leak or a more obvious gush of air. they often sound like a baloon being inflated very quickly. Oil injected into the cylinder is another old school way to determine if it's piston ring-lands/rings or the valves leaking. Then there's the awesome borescopes which take much of the time and stress out of troubleshooting this kind of stuff. Got mine at Harbor Freight and it works great for the price. Could also use just enough compressed air or rope shoved into the chamber at TDC to allow the use of a simple and cheap lever style spring compressor(most big name parts stores carry them) to check valve stem/guide free play/friction. Of course the rockers need to be removed for that check too. Pretty sure those intake and exhaust valves are at different installed heights of each other on those motors due to the rtainers rotators(someone correct me if I'm wrong) but maybe you can get a straightedge across the valvetips or measure all the cylinders retainer heights. Do you have a dial caliper or small machinists ruler to check them out? Unless someone blueprinted the heads correctly.. they'll not be perfectly the same installed spring/retainer heights, but you can get a fair idea if something's obviously wrong. Good luck with it.
with a borescope, you could see if any damage was done to piston top... also...time/money in a car you want to sell...
You convinced me, time to go to harbor freight. Can a spring go bad without being broke? It doesn't appear bad. I do notice when I snack the valve with a rubber mallet it has a deeper hollow sound vs the other valves.
A weak spring will cause valve float a low RPM(compared to others) but I've never seen one cause a idle issue... Have you actually started it since the push rod discovery?? Crud such as rust on valve seat/face, will give erratic compression readings, as long as valve is no longer sticking, run it... Once it's started anything foreign will be blown out the exhaust, but if face or seat is damaged will have low compression on that cylinder... As far as bent valve, it's possible but like a burned or pitted valve, will cause a continual weak/no compression issue... As long as engine has valve reliefs the valve will hit in relief pocket, likely no damage done to piston( a 5.0ngine with your heads should have them)...
I was actually going to mention that too but figured I wouldn't chance feeling responsible if you accidentally dropped a valve when the keepers popped out of the retainer. lol Without results from any quick and dirty tests mentioned above I would guess that you tipped a few valves. Personally, I'd skip the fancy tool and just yank the head to get on with the inevitable.
I know I'm coming in on this late but something does not look right with the valve spring on the right in the picture (maybe #1), it looks like it has some rust/crud on it. Also it looks like there is water in the oil, it looks a little muddy. I have to agree with everyone else you need to pull the heads and have them looked at. It also gives you a chance to check out other things.
Good news.... I was playing with car the other night and discovered that if I pressured the cylinder with my air compressor and then ran a compression test I could get 90-120 on the first test. This gave me hope so I put car back together, improved vacuum routing and cleaned fuel injectors. The car car sounds the best it ever has and nice smooth idle. Only issue I notice is idle seems a little high and I backed the throttle screw down and little change. I will try to get a tach attached so I can get real numbers. Thanks for all your help people.
That's great, crud on valve face/seat as I suspected... The throttle screw will have no effect on idle, it's for setting base idle which is done with IAC unplugged... Base idle should be around 550 RPM, then the computer uses IAC to supply additional air to get proper idle speed... If base idle is too low it can cause idle speed hunt, because it is over cycling... If too high the system can't reduce speed below base idle... Of course vac leak will cause high idle same as with a carb... Once the base idle is set it's time to set TPS voltage, that's done with green & black wires on TPS sensor, set it for .8 to .9v at closed throttle it should be happy... Note some TPS are not adjustable, if that's the case elongate the mounting holes, then adj it for proper voltage... Much over 1v gives a continual high idle...
