Hi on my dads 91 accord an exhaust valve keeps breaking in the #2 cylinder. Its broke twice, took a chunk out of it. the first time we replaced all the valves, spark plugs, wires, and added a MSD.

Once replace it has a problem of not wanting to accelerate till a certain RPM. Once above that RPM it runs fine. Well that magic RPM kept getting higher and higher till the valve broke again. We pulled the head and all the valves looked fine except the two exhaust valves on the #2 cylinder. One had the same problem as before.

So we replaced the two valves and now replaced the fuel injector in the cylinder. Didn't fix the RPM issue. We don't know what else it could be besides the ECU and we pulled that and there seems to be no issues with the board or caps. Before we pick and ECU up for a junkyard i came here to see if anyone has any opinions.

Any and all help will be appreciated. If anything is not clear ill elaborate.

 

im not internal engine expert, but i wanna state an obvious the springs, cam lobes, and rocker arm are all fine on the one cylinder right? nothing different about that one compared to the others?

 

Yea the rocker arm assembly is fine. Also there was some black material on just the 2 exhaust valves in that cylinder.

 

you are going to have to pull the head and inspect all the guides springs and whatnot and also the piston