kevinS2OOO

Hello guys,

Mis-shifted at Thunderhill today going from 5th redline into 4th. I have no idea why I did that before slowing the car down...I am pretty sure I over-revved past 10k.

Anyway, car started acting weird. Rough idle and lack of power in low RPM. I still drove home (probably a bad idea...).

Ran some codes at the track, they were P0420, P0304, and P1399.

I do realize this could be a very expensive mistake, so I am guessing it is cracked retainers, bent valves? Where should I start looking?

Thanks,
Kevin

S_DosMil

Compression and leak down. Probably remove valve cover and see if there is any damage. Possible head swap may be in your future.

B serious

10K momentarily wouldn't do much....or any damage to AP1 or AP2.

So you may have gone higher. In which case, maybe some valves got hit.

Compression and leakdown will tell you.

Chuck S

Hong Kong cars are AP1 (2.0 engine unless it's a JDM model) and red line is 9000. Dropping down from 5th to 4th gear will absolutely take the engine over 10,000 rpm, probably 11,000...

Time to get the valve cover off and see what's broken in there.

-- Chuck

kevinS2OOO

So I am still waiting on my friend to get back in town to take a look.

But what I forgot to add here is the CEL was flashing the whole day I was driving back home from Thunderhill. I looked it up, apparently it's a major misfire that damages the OEM cat to set off another code?

Also, if a valve hasn't dropped, technically the piston and cylinder wall and everything else should be okay?

MorngWoodStewie

Pull valve cover inspect. Cr test maybe, probably kissed a valve.

While it in there swap the retainers if there still ap1

LeonV

Time for a head rebuild...

Sounds like you bent valves on at least #4, if not all the cylinders. It was not good for your cat to drive home that way.

B serious

Hong Kong?

flanders

OP's country of residence is set as Hong Kong, but like many others it seems that might not be so accurate.

windhund116

There's no Thunderhill Raceway in HK, also?

Maybe, OP is originally from Hong Kong?