I get these codes about every week or so. It always happens when the car is in neutral. I do have start up problems ... the engine stumbles a bit at first and then it's fine. the other thing i've noticed is that on part throttle and not in boost, my afr's go very rich. Im running celica 310cc injectors and plan on upgrading soon. But i don't want to jump the gun and throw down for injectors if the ones i have arent bad. Any ideas?

thanks

 

Ok , I'll try and help.
Check the connections on th coils.
Check that the mounting bolts for the coils are getting a good ground , clean the head where they bolt up.
Check your spark plugs , may sound stupid but they may not be performing up to snuff , check gap , torqued down properly , that kind of thing. Don't just assume they are good cause they are new or newer.
You are running boosted so they maybe fouling we not under boost and not cleaning themselves.
You getting good gas ? maybe some water or other contaminate in there ?

Hope this helps you a little , reminding of the simple things.

( and have you tried the injectors from a Rav 4? smaller than 310 but larger than stock)

 

thanks for the suggestions. But, why would you suggest that i go with a smaller injector on a boosted application?

 

I think he was reading into what you stated about running rich at idle..
I like his theory of that causing the plugs to foul at idle ..
seems feasable.. give it some gas and they clean off ..
sounds like whats happening

 

no...i think i have a bad injector. it doesn't always go rich. and it doesnt happen at idle. it happens at part throttle and no boost. ultimate only adds fuel when it sees boost.

 

Do you know what the duty cycle is on your 310cc injectors. I'm starting to think you may have alread maxed out the injectors.

 

duty cycle isn't maxed out. car was tuned so that we didn't overtax the injectors. turns out that the plugs were fouled because my aftermarket thermostat was causing my ecu to stay in open loop adding too much fuel under no boost. I fix this by creating afr map in ultimate to correct the afr's when coolant temp is lower than what the ecu is expecting to see. haven't thrown those codes since.

 

awesome, glad you were able to solve the issue. :D

Misfire code are not something we like to see on our turbo'd cars.

 

Ok well some cheap recommendations...check your PCV valve. if the cylinders are missfiring you might have to hot a gas coming into the intake. not to sound all infomercial-y but try some Stp or techron fuel additive and if all else fails take head off and check for carbon build-up after having checked plugs etc.

I do like the smaller injectors idea...most injectors can handle 10-30cc extra so your turbo will be happy if you get some 255cc or 280's.

Good luck!