Dreaded P0301 Code

[davidkimchee]

Hello all

I have a 1997 camry v6 with 150K miles.

Having trouble resolving a P0301 code.

So far Ive done the following
Changed plugs
Changed wires
Changed coils
Changed Injector

Still the same code and same symptom.


I will clear the code and the car will run perfectly fine but will eventually start to misfire cylinder 1 and shudder. Its very random. Sometimes the car will run fine for 2 days engine light free others 5 minutes.

Compression check shows good compression. All regular maintanence up to date.

Really stumped on this one. Any advice would be appreciated.

David

[STANJ]

P0301= Cylinder 1 Misfire Detected
Hopefully someone can help you diagnose your problem here.

But here's a good idea to look at the problem. If you think it is one of the things you just changed, try swapping them (plugs/wires) to different cylinder and see if the cel is still there. If the CEL is still there, I would say that the fuel injector will be the main suspect.

I have also read about the same problem, and the it was caused by broken exhaust spring.

[csaxon]

Did you notice any moisture in the tubes or on the plugs when you pulled them?

[davidkimchee]

Nope no moisture. Everything appears honkey dorey.

Really stumped on this one.

I gave up trying to fix it and had my dad take it to the mechanic. Its been there three times now and all he keeps doing is the same stuff I did.

Works fine for a while and then stumbles and throws the same code.

Im just gonna give up and let my dad worry about it....his car.

[Nad1370]

Just want to know if you know where cyl # 1 is on a v6 ?

#1 should be the cylinder closest to the cam gear/firewall side.
Just want to know if you replaced the right injector.

Can you tell us also what compression reading you got.

[davidkimchee]

Every time the cars been taken and picked up from the mechanic it was with my father.
I just have him relay the info on what Ive done to the car and what I would like for him to do.

Compression check was on the list and I was told all values were "normal"

I basically tool around with it on the weekends when Im free.

Yeah I know where the number 1 cylinder is so there shouldnt have been a mixup.
I hope the mechanic would know as well.

Ill see if he remembers or if its been noted on any of the paperwork.

Would a burnt exhaust valve allow the car to run fine for brief periods of time?

I just dont know what else to check.

As of now the car is still at the shop. Looks like they still cant figure it out either.
sigh.

[Nad1370]

Really need to know what comp. #'s you got to rule out a sticking rings and carboned up valve seats, ect...
Also can't rule out a bad new injector you just replaced. Was it an OEM part?