Bad intake valve?

[J-440]

Evening all. Started my engine and heard some popping noise coming from the firewall driver side. I managed to limp home with the motor almost dying and sputtering along the way. Now the car won't start and when it does, it still makes that popping noise, idles for about 2 seconds at 300 rpm, and dies. I've went through all the ignition components. MSD box, coil, plug wires, plugs, duel sync distributor and even went through my ECM with no codes. Makes me think its mechanical now. Car only has about 15 miles on it with a fresh rebuild. The motor was sitting for a few years but I was rotating it regularly and keeping it oiled. Any ideas?

[Shawn01754]

Check your intake gasket. Was there any backfire?

[Shawn01754]

Maybe a valve adjustment wasnt locked tight enough

[J-440]

No backfire while I was driving but it did backfire a few times when I was trying to start the car. Also a puff of white smoke came out of the throttle body. I'll also check the valve train again. I've got a compression check gauge but the car won't stay running for me to take a reading.

[Shawn01754]

Intake leak or valve out of adjustment. Did you pull the valve covers?

[TheJDMan]

You did not say but if you have flat tappet lifters with only 15 miles it sounds like you wiped a cam lobe. Pull the plugs and run a compression test. Next, I would pull the valve covers and look for broken valve springs and recheck valve lash then spin the engine by hand and carefully watch the rocker arm movement for each cylinder to verify the camshaft lifter movement. Just FYI, If you have wiped a cam lobe you might as well plan on pulling the engine back out because all that debris will be circulated through the entire engine and will probably have damaged the rod, main and cam bearings.

[J-440]

Thanks for the input guys. Gonna see what I can do this week. Appreciate it.