stuck valve? not sure whats going on..

[joeycarr]

okat to start off i was driving my 00 jeep xj down in denver.. went to give her some gas as the light turned yellow. to my suprise it sound like i roded the motor. it died at the light, i got it started and got it off the road. but it sounded awful like it therw a rod or somthing.. towed it home and to finish it off i get it started and put the pedal to the floor barley runs at all... then the rmps climb and she starts bounceing off the limiter but to my suprise it dont blow up and run back how it did before the stop light.... please let me know what you think!
Thanks in advance!
was thinking stuck valve idk stumped me.

 

[joeycarr]

also i have heard a tic/knock in the motor when driving it. the motor has had a rough life aswell.. had a turbo on it for awhile till i notice the noise and blew a head gasket around the same time i noticed the noise.. its been like 2 months or so since i took the turbo off.
Thanks again!

 

[RCP Phx]

Your going to need a lot more info! I suggest starting with pulling the valve cover and starting your investigation.

 

[joeycarr]

yeah i agree thats the plan, was just wondering if anyone knew why it could go from sounding like rod knock and not moving under it own power to no kncok an driving..
thnaks for your reply!

 

[Agreen]

Detonation or spark knock can sound like rod knock.

It's hard to diagnose over the internet, so I'll give you a few things to check.
1) spark plugs
2) did you gas up recently? (May be bad gas?)
3) if you're worried about engine damage, check compression
4) since it's a 2000, maybe it was vapor locking? Usually it's a no-start issue, but it could have flashed the fuel to vapor in the rail and made the spark knock noise?

Just theories here, because obviously the car isn't in front of me. It could even be due to low fuel pressure. Just don't rule anything out quite yet.

 

[halmca]

Did you notice oil pressure before the trouble, check compression, check fuel pressure, then avail yourself of your Jeep's OBD (on board diagnostic) port and see what codes are set, if any.

PS: in more than sixty years of wrenching I have never encountered a stuck valve in an engine unless a valve and piston attempted to occupy the same space, or unless the engine had cooled its jets under an elm tree for a decade or five.